STUDIES ON DEHYDRATION OF DENDROBIUM ORCHID FLOWERS

Transcription

1 STUDIES ON DEHYDRATION OF DENDROBIUM ORCHID FLOWERS RAMEEZA SALMA PHK 804 DEPARTMENT OF HORTICULTURE UNIVERSITY OF AGRICULTURAL SCIENCES BANGALORE 2010

2 STUDIES ON DEHYDRATION OF DENDROBIUM ORCHID FLOWERS RAMEEZA SALMA Thesis submitted to the University of Agricultural Sciences, Bangalore In partial fulfillment of the requirements for the award of the degree of MASTER OF SCIENCE (HORTICULTURE) in Floriculture and Landscape Gardening BANGALORE AUGUST, 2010

3 Affectionately t dedicated di d to my beloved parents Md. Zahir and Azmathunnisa and my dear guide

4 DEPARTMENT OF HORTICULTURE UNIVERSITY OF AGRICULTURAL SCIENCES BANGALORE CERTIFICATE This is to certify that the thesis entitled STUDIES ON DEHYDRATION OF DENDROBIUM ORCHID FLOWERS submitted by Ms. RAMEEZA SALMA, ID No. PHK 804 for the award of the degree of MASTER OF SCIENCE (HORTICULTURE) in FLORICULTURE AND LANDSCAPE GARDENING to the University of Agricultural Sciences, Bangalore, is a record of research work carried out by her during the period of her study in this University under my guidance and supervision and the thesis has not previously formed the basis for the award of any degree, diploma, associateship, fellowship or other similar titles. Place: Bangalore Date: AUGUST, 2010 SANGAMA Major Advisor Approved By: Chairperson : (SANGAMA) Members : 1. (D.P. KUMAR) 2. (R. JAYANTHI) 3. (D. M. GOWDA)

5 ACKNOWLEDGMENT This thesis would not has been accomplished without the will of Allah and the generous assistance of numerous contributors. I extend my heartfelt gratitude to the chairperson of my advisory committee, Dr. Sangama, Senior scientist (Horticulture), Division of Post harvest technology, Indian Institute of Horticultural Research, Hesaraghatta, Bangalore for her supervision, advice and guidance from the very early stage of this research as well as giving me extraordinary experiences through out the work. She provided me unflinching encouragement and support in various ways. I thank my madam for creating a friendly environment in workplace and boosting confidence in me with true mother care which helped me to concentrate more on work without any difficulties. I express my deep sense of gratitude to the co-chairperson of my advisory committee, Dr. D. P. Kumar, Professor and Head, Division of Horticulture, UAS, GKVK, Bangalore, for his worthy suggestions, constant encouragement, care and sincere advise inspite of his busy schedule throughout the course of the study. His involvement with his originality has triggered and nourished my intellectual maturity that I will benefit from, for a long time to come. I place on record my deep sense of gratitude, respect to my teacher and member of my advisory committee, Dr. R. Jayanthi, Professor of Horticulture, Division of Horticulture, UAS, GKVK, Bangalore for being a source of inspiration for my research work. I am grateful to madam for the true care, affection and support with valuable suggestions. I also thank Dr. D. M. Gowda, Department of Agricultural Statistics, UAS, GKVK, Bangalore for his guidelines and advice during the course of this investigation. My heart starts blooming when I recall all my friends Ari, Ashi, Kammu, Deepa, Balu, Dhanya, Savitha, Prema, Shwetha,Musa, Pavan, Parmesh, Kafayath, Pooja, Ansu, Suma, Kavitha, Shahin, Swathi,Varalakshmi and Hema.

6 Many thanks go in particular to my dear friends Prema, Mostariji, Sindhu and Shankar and my senior friends Laxmi,Vasantha, Ravichandra and Anitha for their unquantifiable support. Where would I be without my family? My Ammi, Abna deserve special mention for their inseparable support and prayers. My brothers Adil, Hidayath and my sister Shabnam who constantly supported me with true care and affection. I gratefully acknowledge Dr. G. P. Brahamaprakash, Professor, Dept. of Agricultural Microbiology, UAS, GKVK, Bangalore for his advice, supervision and crucial contribution to this thesis. I thank Mr. H. C. Siddaveera Aradhya, Technician, Division of PHT, I.I.H.R, Bangalore for his help during the study. I also thank Dr. Ranjitha, Dr. Sudhakar Rao and other staff members of PHT division for their support during my work. I heartfully thank my Chanqhala, Chanqhalai and their family persons Siddiq, Hajira, Sadath and Sayeed for creating a homely feel with their love and warmth which made life away from home burdensless. I also thank my Mama and Mami for their sincere care and affection on me. Finally, I would like to thank everybody who was important to the successful realization of thesis, as well as expressing my apology that I could not mention personally one by one. Bangalore August, 2010 (Rameeza Salma)

7 STUDIES ON DEHYDRATION OF DENDROBIUM ORCHID FLOWERS RAMEEZA SALMA ABSTRACT Dehydration is an important process of moisture removal to enhance the shelf life and preserve the flower colour, shape, size and texture in natural form. Dried flower quality is depends on flower structure, variety, stage of harvest, time of harvest, desiccants, drying methods and their storage in a suitable packages. Hence the present study was conducted with the objectives of selection of suitable varieties with optimum harvest stage, embedding media and drying method for better display quality with longer shelf life of dried flowers of Dendrobium orchid. Dried flowers of Dendrobium orchid var. Sonia-17 had higher sensory score of 22.80, and for colour, texture and shape respectively as compared to the dried flower sensory score of and 14.60, and and for colour, texture and shape respectively in vars. Caesar Red and Emma White. Among three harvest stage viz., half opened, ¾ th opened and fully opened flowers of Dendrobium orchid var. Sonia-17 dried flower qualities revealed that flowers harvested at ¾ th opened stage yielded dried flowers of brighter colour, glossy texture, medium in size with small white centre having sepals and petals in intact position. Silica gel embedded hot air oven dried flowers obtained a sensory score of and for colour and shape respectively whereas better texture (22.12) was maintained in sand embedded hot air oven dried flowers. Dried flowers stored under dark in an air tight plastic container obtained a sensory score of and for colour and texture respectively indicating good keeping quality of above six months. Among various value added products prepared from these dried flowers, floral arrangement in acrylic package obtained maximum sensory score of as compared to dried flower arrangement in bamboo basket and dried labellum greeting card. Department of Horticulture UAS, GKVK, Bangalore-65 (SANGAMA) MAJOR ADVISOR

8 CONTENTS CHAPTER TITLE PAGE No. I INTRODUCTION 1-3 II REVIEW OF LITERATURE 4-23 III MATERIAL AND METHODS IV EXPERIMENTAL RESULTS V DISCUSSION VI SUMMARY VII REFERENCES APPENDIX

9 LIST OF TABLES Table No. Title Page No. 1. Fresh and dry weight of flowers of Dendrobium orchid varieties Per cent moisture loss, drying rate of fresh flowers during drying and flexibility of dried flowers of Dendrobium orchid varieties Colour (L* a* b*) of fresh flowers of Dendrobium orchid varieties Colour (L* a* b*) of dried flowers of Dendrobium orchid varieties Sensory score of colour, texture and shape of dried flowers of Dendrobium orchid varieties Diameter of fresh and dried flowers of Dendrobium orchid varieties Fresh flower petal, sepal and labellum size of Dendrobium orchid varieties Dried flower petal, sepal and labellum size of Dendrobium orchid varieties Effect of harvest stages on fresh and dry weight of flowers of Dendrobium orchid var. Sonia-17 Effect of harvest stages on per cent moisture loss, drying rate of fresh flowers and flexibility of dried flowers of Dendrobium orchid var. Sonia-17 Colour (L* a* b*) of different harvest stages of fresh flowers of Dendrobium orchid var. Sonia-17 Colour (L* a* b*) of different harvest stages of dried flowers of Dendrobium orchid var. Sonia-17 Effect of harvest stages on sensory score of colour, texture and shape of dried flowers of Dendrobium orchid var. Sonia-17 Effect of harvest stages on fresh and dried flower diameter of Dendrobium orchid var. Sonia-17 Effect of harvest stages on petal, sepal and labellum size of fresh flowers of Dendrobium orchid var. Sonia

10 Table No Title Effect of harvest stages on petal, sepal and labellum size of dried flowers of Dendrobium orchid var. Sonia-17 Effect of embedding media, drying methods and positioning on dry weight, per cent moisture loss, drying rate (g/h) and flexibility(º) of Dendrobium orchid var. Sonia-17 flowers Effect of embedding media, drying methods and positioning on sensory score of colour, texture and shape of dried flowers of Dendrobium orchid var. Sonia-17 Effect of packaging and storage condition on sensory score of dried flowers of Dendrobium orchid var. Sonia-17 Effect of packaging and storage condition on flexibility and shelf life of dried flowers of Dendrobium orchid var. Sonia-17 Sensory score of dried flower products of Dendrobium orchid var. Sonia-17 Page No

11 LIST OF FIGURES Figure No. Title Between Pages 1. Fresh weight of flowers of Dendrobium orchid varieties Dry weight of flowers of Dendrobium orchid varieties Per cent moisture loss of flowers of Dendrobium orchid varieties Drying rate (g/h) of flowers of Dendrobium orchid varieties Effect of harvest stages on fresh weight of flowers of Dendrobium orchid var. Sonia Effect of harvest stages on dry weight of flowers of Dendrobium orchid var. Sonia Effect of harvest stages on per cent moisture loss of flowers of Dendrobium orchid var. Sonia Effect of harvest stages on drying rate of flowers of Dendrobium orchid var. Sonia

12 LIST OF PLATES Plate No Title Fresh Flowers of Dendrobium orchid varieties a. Sonia-17, b. Emma White and c. Caesar Red Harvest stages of Dendrobium orchid var. Sonia-17 flowers a. Half opened, b. ¾ th opened and c. Fully opened Between Pages Embedding of Dendrobium orchid flowers in Silica gel Measurement of flexibility Colourimeter Embedding of Dendrobium orchid var. Sonia-17 flowers in silica gel under ambient condition Packaging and storage of dried flowers of Dendrobium orchid var. Sonia-17 a. Dark and b. Light Dried flowers of Dendrobium orchid varieties a. Sonia-17, b. Emma White and c. Caesar Red Dried flowers of Dendrobium orchid var. Sonia-17 harvested at a. Half opened, b. ¾ th opened and c. Fully opened stage Dried flowers of Dendrobium orchid var. Sonia-17 a. Silica gel b. sand and c. Silica gel and sand embedded in hot air oven Silica gel embedded hot air oven and ambient dried flowers of Dendrobium orchid var. Sonia-17 Dried flowers of Dendrobium orchid var. Sonia-17 stored under a. Dark and b. Light in an air tight plastic container Dried flower products of Dendrobium orchid var. Sonia

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14 I INTRODUCTION Flowers are mentioned in the social fabric of our country and no function is complete without flowers. The dried flower industry is growing at an annual growth rate of 10-20%. During 2009, the turnover was estimated to be Rs. 1,000 crores and out of which Rs. 400 crores of contributions was from Delhi alone and rest Rs. 600 crores was from other major cities like Bangalore, Mumbai, Chennai and Chandigarh. India produces wide varieties of floricultural products, which include flowers and foliage, both fresh and dried flowers such as roses, carnations, chrysanthemums, gladiolus, gerbera, anthurium and orchid. The overall exports of floricultural produce from India increased to Rs crores by the end of from Rs crores at the beginning of The export basket comprises dried flowers (71%), fresh cut flowers (18%), live plants (9%), fresh bulbs (1%) and cut foliages of 1% (Singh, 2009). Orchids, the most fascinating and beautiful of all flowers. They belong to the family Orchidaceae that comprise of about 800 genera and 25,000 species around the world. The exquisite diversity in colour, size and shape of these orchid flowers make them highly priced among the ornamental plants. Majority of the cultivated orchids are native of tropical countries. They are excellent items for garden and cut flowers. Dendrobium is a diverse genus of orchids with more than 1000 natural species and are commonly used as a cut flower because of their sturdy stems and distinctive colours. They still ooze glamour and elegance with just a couple of stems adding a sophisticated touch to floral arrangements in any area. The beauty and fresh look of cut flowers can be retained only for few weeks even by the best techniques of post-harvest technology but the charm of dried flowers and foliage can be maintained from a few months to years with lesser cost if protected from the damage of high humidity. Drying and preserving flowers and plant materials is a form of artistic expression that was very popular during the Victorian age and has once again gained popularity. Dried flower industry is 30 to 40 year old which was brought to India by British and prospered in Kolkata because of its proximity to North East where diverse blooms are

15 available in abundance. Tuticorin is another important hub of dried flower industry of South India. In the Indian market, dried flowers hold a tremendous potential as they are cheap, have long shelf life and are eco- friendly. The romantic renaissance of country decorating has brought with it a return of the craft of drying flowers. Even with the increased popularity of plastic and fabric flowers (silk for example), many people still prefer "the real flowers" preserved in a life like manner. Dried flowers are considered as value added products in floriculture industry and they are the major items for export and constitute 70 percent of the total share of floriculture products of export from India (Singh, 2005). Although, dried flower production is a small component of Indian floriculture industry, but the demand of Indian dried flowers and plants has sharply increased world over in a short span. The dehydrated or dried ornamental plant parts are generally inexpensive and are sought for their everlasting and attractive appearance (Smith, 2000). By drying in absence of moisture the microbial activity, causing the ageing effect is drastically reduced. The main qualities of dried flowers include novelty, longevity, aesthetic, flexibility and year round availability (Joyce, 1998). Liberalization of EXIM policy in India has paved the way for increased export of floricultural products and the contribution of dried flowers is enormous. India is one of the major exporters of dried flowers to the tune of 5% world trade in dried flowers. This industry shows an average growth rate of 15% annually. Because of extreme cold in European countries and extreme hot in arid and deserts there is tremendous export potential for this industry. Being of low cost and having high demand, small scale dried flower industry can be started at various parts of the country. Export of these products constitutes nearly 60%. In this dried flower industry, a turnover of more than Rs. 150 crores is projected every year (Patil and Singh, 2008). The dried flowers are mainly exported to US, Israel, Hongkong, Japan, Singapore and West European countries. Today s approach to dried flower displays is to emphasize colour and texture by using massed materials so that the collective strength of their qualities create impact. The

16 dehydration industry of floral produce can provide creative employment to thousands of unemployed youths, women and rural people for their extra income. It can be taken up on small scale industries yielding rewardable results in rural areas. However, this important aspect is totally neglected in research work. The floriculture is an ancient creative skill with imagination and an advanced science that played a very important role in the course of human civilization and its social development. The ornamental crop industry is characterized by constant change, activities, new ideas and is a fast flowing international enterprise of potential excellence, unique in character and function. The global ornamental crop industry is worth about US $70 billion. At present, the dried flower industry is not well organized and depends on plant material available in forests and no systematic growing of specialized flowers exists anywhere in the country. The demand for dried flowers is increasing at an impressive rate of 8-10% and therefore there is a great scope for the Indian dried flower entrepreneurship. In India, though there is a tremendous export potential of dried flowers but till date no systematic research has been carried out to improve the dried flower quality. Viewing uprising potentials of flower drying trade, its practical utility in our country and gap of research in this aspect, the present studies on dehydration of Dendrobium orchid flowers was undertaken. The overall goal of this study was to develop processes to produce good quality dried orchid flowers. In view of this, the specific objectives of this study were: 1. To find out a suitable Dendrobium orchid variety for superior quality of dried flowers 2. To determine an optimum harvest stage for better quality of dried flowers 3. To evaluate the effect of embedding media, drying methods and positioning of flowers on dried flower qualities. 4. To study the effect of packaging and storage conditions on shelf life of dried orchid flowers. 5. Product diversification of dried flowers of Dendrobium orchid.

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18 II REVIEW OF LITERATURE Flowers have always remained an integral part of human life, they are the inseparable part of human joy and sorrow. Their exquisite beauty, fresh looks, diverse colours cast their spell on but only for a short time and are available in a particular season. The charms and beauty of these plant parts, however, can be maintained for months to years by employing various techniques of dehydration. The literature available on systematic research work of dehydration of flowers is scanty. However, the available information is reviewed in this chapter. 2.1 DEHYDRATION PROCESSES OF FLOWERS Selection of materials Plants for preserving may be collected throughout the year. For drying purpose flowers of various shapes, colours and textures at different stages of development can be picked. Avoid collecting plants when they are wet (Gouin, 1994). Stems, twigs, branches, bark, foliage, flowers, fruits, cones, roots, ferns etc. can be utilized for making various value added floral crafts and flower arrangements which are non- perishable and have longer life (Raj, 2001). Webb (2002) suggested that a large variety of flowers can preserve well which includes daffodils, carnations, delphinium, geranium, hibiscus, honeysuckle, hollyhock, jasmine, lavender, iris, marigolds, tulips, sunflowers, roses and violets Time and Season of Harvesting Evans and Davis (1998) suggested that herb flowers harvested to dry for craft purposes should be picked just before they are fully open, UV rays from the sun, moisture from dews and frost can discolor and severely reduce the quality of many herbs. Plant parts can be harvested at different stages of development for variation in color, form and texture (Musgrove, 1998).

19 The best time to harvest plant material is late morning, after the dew has dried but before the heat of the afternoon and over-mature flowers should not be harvested as they tend to shatter once dried (Smith and Laschkewitsch, 1998). Winter (1998) suggested that picking of flowers should be in the middle of the day and proper ventilation should be given for proper drying. Frogge (2000) suggested that the flowers to be dried should be picked just before they are at peak maturity and the petals are free of moisture. The flowers should be free of injury or bruises because these conditions will become more evident after the drying process. Dana and Lerner (2002) reported that materials such as dry grasses, seeds, pine cones and most seed heads should be harvested in the full at the end of their growing season but before they become withered in appearance and also suggested that flowers should be harvested before they reach full bloom and foliages should be collected at the peak of the growing season. Paul and Shylla (2002) suggested that the flowers should be harvested just before they are fully open and the colour fades. Harvesting should be done preferably in the mid- days when the sun is at its hottest peak. Spielberg (2002) suggested that the flowers should be harvested on dry sunny days. Most can be picked as their blooms start to open, but particular care should be taken with Helichrysum, whose flowers will disintegrate in storage if they are picked too late. Jauron (2003) reported that collecting flowers at the proper growing stage is vital to ensure high quality plant material. The proper time to harvest specific flowers varies with the crop. Datta (2004) suggested that the material for drying should be collected a day or two after irrigation of the field and there should not be any surface moisture. It s better to collect the flowers and foliage in dry season than in sunny day.

20 The best time to harvest most herbs for drying is just before the flowers first open when they are in the bursting bud stage (Andress and Harrison, 2006). Plant material is best harvested in late morning on a sunny day which ensures the flower head is dry and some flowers collected past their prime tend to lose their petals during the drying process (Anon., 2006). Bale (2006) reported that no matter which drying method is adopted but the flowers should be harvested at the correct time, before they reach their peak. Flowers and leaves for drying may be collected at any time during the growing season from early spring until late fall. Use only plants and flowers free of insect and disease damage as the damage becomes more obvious after drying (Trinklein, 2006). Harvesting should be done when flowers have reached near peak and haven t started to fade or turn brown around the edges. Flowers that are too mature can drop their petals easily during the drying process (Anon., 2007). White et al. (2007) reported that dry materials should be harvested in good condition, usually in the fall of the year at the end of their growing season but before they become withered appearance, foliages should be collected at the peak of its growing season and in perfect or near perfect condition at early maturity but not at full bloom stage. Odell (2009) stated that marigold flowers should be collected in the early morning when the flower heads are fully open. 2.2 DRYING METHODS Air drying Susan (1990) reported that flower with crisp texture such as straw flower, statice etc suit to this technique of drying. It is simple and cheap as well. However, drying period is more and such flowers possess a naturally straight stems upon drying.

21 Martha (1995) reported that air drying is very successful with herbs, everlastings and ornamental grasses. This method works well with roses. Barnett (1996) reported that air drying is the simplest method of preserving plant materials. It is the preservation of plant materials without the use of chemicals or desiccants. The ideal environment for air drying will be dark, warm, clean, dust free, well ventilated and most important dry. Plant materials are bunched together in groups of not more than 10 stems and each bunch should contain only one plant variety. Leaves should be removed from the lower half of the stem before drying. Drying rates vary from plant to plant and are subject to factors such as atmospheric conditions, bunch sizes and temperatures etc. Karth (1997) reported that air drying is the traditional method of drying flowers. Air-drying can be done by tying the herbs into a bunches and hung them in a well ventilated room. Drying of flowers depend on humidity, arrangement and type of flowers. Thomler (1997) reported that flowers could be air dried by positioning them in a dry container with or without water either by laying them flat or by suspending in a mesh. Musgrove (1998) reported that Helichrysum flowers were best suited for air drying method in a warm, dry and dark area that has good air circulation. Smith and Laschkewitsch (1998) stated that air drying is the easiest and low cost method of preserving flowers and also suggested some flowers suitable for air drying include strawflower, golden rod, hydrangeas, celosia (crested and plumed types), statice, baby s breath and salvia. Pavildou (1998) has reported that the species such as Achillea millefolium, Craspedia globosa, Delphinium consolida, Helichrysum bracteatum, Helipterum roseum, Helipterum manglesii, Limonium ottolepis, Limonium perezii, Limonium sinuatum and Limonium suworowii are suitable for dried flower production. All the above species are easily dried in a dark ventilated room at 30 0 C for the first week and at 20 0 C for the following 2 to 3 weeks to maintain their color and quality characteristics

22 Christy (1999) reported that herbs which are being dried should be protected from direct sun light and provided good air circulation. Anon. (2000) reported that long stemmed herbs such as lavender, marjoram, some mints, rosemary, sage, savory and yarrow are easy to air dry in bunches. Short stem and small leaves like thyme are placed in trays and spread in a thin layer for better results. Frogge (2000) reported that some of the wild flowers that can be air dried are Solidago spp, Cat tails (Typha spp), Indian grass (Sorghastrum nutans), thistle (Cardurs spp) etc. Anon. (2001) suggested that air drying can be very successful with herbs, everlasting and ornamental grasses, straw flowers, golden rod, celosia, statice, zinnia and baby s breath, globe amaranth, salvia, artemisia etc. Dana and Lerner (2002) reported that air drying is the simplest method of drying works well with plants having semi dried flowers and done in cool, dark place for about 3 weeks with good air circulation. Datta (2004) reported that air drying is one of the most simple and low cost method of dehydration as the flowers are dried in natural condition. Major drawback of this method is that it is weather-dependent and the quality of the product is not good. Supriya (2004) has reported that air drying is the classical method of drying flowers. This method suits best for flowers with less moisture. Air drying should be done in closed cellar as the dark places help the flowers to preserve its natural color. Dubois and Joyce (2005) reported that one way of increasing the drying rate is to raise the air temperature. The best temperature range for drying plants is between 60 C and 80 C. If the temperature is greater than 60 C, the enzymes which catalyses reactions within the plant tissue will be destroyed, this is desirable because some enzymes are responsible for chemical reactions which result in browning (for example, polyphenol oxidase).

23 Schmutze and Hoyle (2007) reported that air drying is the simplest way to dry sage, thyme and parsley results in better colour and flavor retention. Singh and Kumar (2008) reported that Chinese lantern, baby s breath, poppy seed heads and Globe thistles dry better right side up in air drying Embedding of flowers in silica gel Susan (1990) reported that this technique was advantageous to produce exquisite life like flowers in both form and colour. Difficult to dry flowers can also be dried using desiccants. But it is a costly method and desiccated flowers are more fragile and vulnerable to atmospheric moisture. Silica gel was suggested to be a superior medium than sand or borax for speedy drying of flowers (Anon.,1997). Silica gel method of flower drying was reported excellent for retaining the colour of flowers (Champoux, 1997) Roberts (1997) reported that silica gel, a drying agent had the capacity to absorb large quantities of moisture (up to 40%) and could quickly dehydrate cut flowers like cosmos,aster, calendula, dahlia and candy tuft. Musgrove (1998) reported that flowers can be dried in one of the three positions flat faced flowers such as daisies and corn flowers dry well when placed face down in drying mixture, elongated, spike type flowers should be dried horizontally, all other flowers dried face up. Drying time varies depending on the flower thickness and the drying agent used. Silica gel requires 2 days for thin textured flowers and 5-7 days for heavier textured flowers. Borax mixture generally require from 5 days to 3 weeks, depending on the flowers texture. Dyk (1998) reported that silica gel is the best material for drying flowers. He also reported that it is rather expensive and can be used indefinitely. Frogge (1998) reported that some wild flowers suited for desiccant drying such as blanket flowers (gaillardia x grandiflora), maximillian sunflower (Helianthus maximillian) and black eyed susan.

24 Smith and Laschkewitsch (1998) stated that silica gel can be used to dry flowers which includes rose, aster, carnation, marigold, dahlia, zinnia and chrysanthemum within hrs. Winter (1998) reported that silica gel appears white in color and sometimes contains blue crystals that act as an indicator of the amount of moisture absorbed. As the moisture is absorbed from the flowers, the crystals gradually turn pink. Flowers drying in silica gel must be placed in air tight containers such as candy tins, plastic containers or cans. Christy (1999) suggested that silica gel has greatly widened the varieties of flowers can be dried, it is light in weight, flows easily, which makes it easy to surround all the parts of the flowers for fast drying. It takes days to dry and not suited for air drying can now be dried through the silica gel such as rose, pansy, zinnias, delphinium etc. make good dried flowers. Silica gel could be an excellent product for drying flowers though more expensive than other materials. Because of its light weight, it does not tend to flatten the flowers and is faster acting than borax mixtures (Day, 2000). Kumari and Pieris (2000) suggested that silica gel can be used as a embedding material for rose and statice to obtained the high quality standards. Anon. (2001) reported that silica gel absorbs moisture from flowers rapidly preserving color better than other drying methods takes hours suitable flowers like rose, aster, carnation, marigold, dahlia, geranium, zinnias, chrysanthemum, delphinium, hydrangea, salvia, orchid, gerbera etc. Dana and Lerner (2002) reported that two most satisfactory desiccants used are sand borax mixture and silica gel others such as kitty litter, perlite, saw dust, corn starch and corn meal can be used but it is not reliable. And also suggested that borax - sand method of drying takes 4-14 days. Gill et al. (2002) observed that flowers of rose, carnation and Helichrysum gave best result when dried by embedding in silica gel.

25 Harten (2002) reported that the embedded drying was suitable for most of the flowers and foliages to retain their shape and bright colours for a very long time. Paul and Shylla (2002) reported that flowers like anemone, snapdragon, cosmos, freesia gave best result when dried by embedding in silica gel. Pertuit (2002) reported that silica gel can absorb about 40% of its weight with water and suitable for closely packed flowers like rose. Sandhu (2002) described silica gel embedding as the appropriate method for proper colour retention of Helichrysum and statice. Raj and Gupta (2003) reported that among four desiccants (boric acid, silica gel, river sand and saw dust) tried, silica gel has been found best absorbent for removing moisture from foliages and flowers. The results revealed that dehydration at 40 C with silica gel for 24 h were found to be effective technique for dehydration of zinnia flowers (Singh et al., 2003). Sangama (2004) reported that drying was faster (16-18 hours) with fully open stage flower in silica gel embedded in a hot air oven drying and slowest(5-9 days) without embedding in shade drying of tight bud stage of Helichrysum flower. Supriya (2004) has reported that flowers with fragile petals like anemone, daisies, pansy and zinnia dry best with silica gel. Dubois and Joyce (2005) reported that many delicate flowers irreversibly lose structure during normal air drying. The petals may be held in the desired shape by supporting the flower in fine grained sand which has been thoroughly dried in an oven. Silica gel, cornmeal and Kitty Litter may also be used and have the advantage of faster drying because their desiccant activity extracts water from the petals. Drying normally takes only one or two days, with excellent colour retention.

26 Raj and Gupta (2005) reported that silica gel has been found the best absorbent for removing the moisture from the flowers followed by boric acid and solar dryer which is an economically cheaper method of dehydration. Dry (2006) has given a list of the flowers which are suitable for embedded drying in silica gel viz., rose, aster, carnation, marigold, dahlia, larkspur, geranium, zinnia, chrysanthemum, delphinium, amaryllis, anemone, calendula, safflower, celosia, narcissus, gerbera, camellia and orchid. Bale (2006) reported that chrysanthemums when dried by facing upside in desiccants took four weeks for better shape and size. Safeena et al. (2006) reported that drying different varieties of rose with silica gel gave good result for Lambada dried at 40 o C were more acceptable for colour (2.51), appearance (2.52) and texture (2.38). Dhatt et al. (2007) reported that silica gel embedding was the most suitable method of dehydration with respect to colour and shape retention in rose cvs. Gold Medal and Christen Dior Schmidt (2005) stated that desiccants like silica gel was found to be best drying agent for aster (2-4 days), cosmos, gladiolus, Rosa sp (2-3 days ) and Tagetus sp. (3-4 days). The optimal dehydration effects could be obtained when Rosa hybrida was dried in the mixture of silica gel and common salt (volume ratio is 3:1) for 240 hours under 15 ºC, Eustoma grandiflorum in the mixture of silica gel and common salt for 54 hours under 45 C and Cosmos sulphurens in the mixture of silica gel and common salt for 8 hours under 45 C (Ye and Hua, 2008). Singh and Kumar (2008) suggested desiccant drying of roses, carnation, marigold, lilies and dahlias are preserved in the dried state for long time and silica gel is used to dry multi petalled flowers such as dahlias, zinnias and daisies.

27 Flowers like azaleas, daisies, marigolds, orchids, pansies,roses, zinnias can be dried with Silica gel usually results in more vibrant colors and better preserved shapes than the air drying (Dryness, 2009). Singh et al. (2009) reported that silica gel embedding was found to be most suitable desiccant for good appearance and smooth texture of flowers petal whereas copper sulphate embedding was most suitable for obtaining brighter flower Embedding of flowers in sand Rose, gerbera and carnation flowers were dried for 10, 15 or 20 days in river sand mixed with borax in various proportions.the results revealed that river sand containing a high proportion of borax and a drying time of 15 or 20 days were considered the best conditions for roses and carnations (Orduno-cruz and Baltazar-bernal, 1995). Martha (1995) reported that sand drying can be used to dry a wide variety of flowers, such as roses, tulips, dahlias, marigolds and snapdragons. Daisy type flowers should be dried face down. Snapdragon, lilac, elongated flowers and flowering branches should be positioned horizontally in the sand and the flowering branches face up. Anon. (2001) reported that roses and cup shaped flowers are dried face up, daisy type flowers dry face down and snap dragons and other elongated flowers are placed horizontally on to sand. In an experiment for dehydration, the floral parts were placed in sand beds in racks placed in a hot air oven. The colour and structure of the floral parts showed no change after dehydration. Total chlorophyll was significantly reduced in the dehydrated parts, compared with the control (Pandya and Saxena, 2001). Anon. (2004) reported that sand can be used to dry a wide variety of flowers such as roses. tulips, dahlias, marigolds and snapdragons. Flowers which last only one day like day lilies do not dry well, daisy type flowers should be dried face down, elongated flowers and flowering branches should be positioned horizontally and flowering face up, rose, peonies and tulips should be dried face up.

28 Among desiccants tried sand embedded dried flower display quality was better with respect to colour (3.03), shape (2.96) and with smooth textured (2.89) petals as compare to dried flower with shriveled petals under control (Ravichandra, 2005). White et al. (2007) reported that sand drying is the oldest, least expensive and best desiccant and it should be dry, fine, washed several times with water to make salt free Hot air oven drying According to Kher and Bhutani (1979) a temperature range of C for 48 hrs was ideal to dry gerbera, chrysanthemum, gomphrena and gerbera. China aster, rose buds Helichrysum and zinnia were dried at C in 48 hours. Dahlia and narcissus were dried in 72 hours at C. Naeve (1996) suggested that silica gel was the best agent for drying flowers. Aster, dahlia, rose, chrysanthemum, pansy, marigold may be dried at 250 º - 300º F. According to Joykumar (1997) different drying techniques have a strong effect on the quality of the flower. Hot air oven 50º C took lesser time for drying in aster(36 hrs), rose (30 hrs) and chrysanthemum(22 hrs) as compared to shade drying which requires 66, 80 and 90 hours respectively for the same flower. Christy (2000) suggested that a drying temperature of around 75 0 C seems to give the best results with good air circulation and dry weather for most of the herbs will be sufficient to complete drying in 7-8 days. According to Raju (2001) oven drying of china aster flower using white sand as the medium is the best for retention of colour, shape and texture of dried flower. Vethamoni and Nanthakumar (2002) observed maximum moisture loss in flowers of Achillea filipendulina, Helichrysum bracteatum, Salvia leucantha, Tagetes erecta, Solidago canadensis, Hydrangea hortensis and Aster sp. when subjected to oven drying.

29 Dahiya et al. (2003) reported that the best quality of dried flowers were obtained by embedding them in silica gel and keeping at 50 C for 48 hours in the oven as the per cent decrease in weight and moisture content was maximum. Misra et al. (2003) has listed different flowers suited for oven drying. After dehydration, yellow flowers retain their colour properly, but white become off- white, red, blue and other bright ones become considerably dark. Crepeau (2005) says that food dehydrator works very well for rose drying when the temperature is set between 95 to 100 C for 8 to 24 hrs depending on the size of the bloom and the bloom will shrink about 50%. Dubois and Joyce (2005) stated that Microwave energy has the peculiar attribute of being preferentially absorbed by water and hence is a particularly efficient energy source for the process of drying. To date only experimental quantities of flowers have been dried using microwave. Bhalla et al. (2006) reported that the present ability of hot air oven dried flowers was maximum under covered condition when they were dried for 24 hour at 60 o C using silica gel. In contrast, microwave oven dried flowers for 90 sec embedded in silica gel scored maximum points under covered condition. White et al. (2007) also reported that cooking time vary depending on the characteristic of a leaf or flower, after cooking flowers must be left in the drying agent for several hours called standing period. Roses (2.5 minutes heating time, over night standing time), zinnia, chrysanthemum, marigold takes (1.5 min heating time and 10 hrs standing time), large chrysanthemum (3 min heating time and 36 hrs standing time), orchids ( 1.5 min heating time and 24 hrs standing time). Meman et al. (2008) reported that drying of Calendula flowers embedded in borax at low temperature in hot air oven exhibited well maintained flower shape, smooth petal texture, less mechanical damage during handling and acceptable colour.

30 Singh and Kumar (2008) suggested that marigold, zinnias,corn flowers, lupins and chrysanthemums are easily dried by oven drying method. The results revealed that percent moisture loss and reduction in width (cm) of leaf was significantly highest at higher temperature and silica gel during entire process of drying from 4 16 th h of drying (Meman and Barad, 2009) Microwave oven drying Dana and Lerner (2002) reported that microwave drying of chrysanthemum and marigold takes 3 minutes heating time, 10 hrs standing time, rose 1 to 1.5 minutes heating time and 10 hrs standing time and zinnia 4-5 minutes heating time and 10 hrs standing time. Aravind and Jayanthi (2004) reported that best quality dried flowers of chrysanthemum (Dendranthema grandiflora Tzvelev) were obtained by microwave oven drying with powdered silica gel as embedding medium with flowers were dried at 80 percent micro power level for 120 seconds. Microwave dehydration had decreased the dehydration time of flowers, fruits and vegetables with higher energy and drying efficiency with better color and texture (Khamis et al., 2005). Liang et al. (2005) concluded that the flowers dried by Freeze Drying and pretreated with 10% tartaric acid solution before Microwave drying had a good colour and appearance. Bale (2006) suggested that micro wave drying in combinations with desiccants gives fresher look and retains colour, chrysanthemum takes 3 minutes and zinnia (4-5 minutes) of heating time and 10 minutes of standing time. Bhalla et al. (2006) tried three different drying media viz., river sand, silica gel and a mixture of river sand and silica gel (1:1, v/v) and were kept at three durations in

31 microwave oven. Minimum size reduction and maximum carotene content was obtained when flowers were embedded in silica gel for 30 sec in microwave oven. Nirmala et al. (2008) reported that in microwave oven drying method, maximum flower dry weight was recorded with quartz sand at 120 seconds duration of drying. Maximum dry flower diameter was observed with quartz sand at 120 seconds and maximum number of petals was recorded with quartz sand Press drying Pressing is a method of preserving plants to use on pictures, stationery, place cards etc. Most foliage and simple flowers with few petals press very well. Pansies are an excellent flower for pressing at all stages of flower development and even leaves and branches with foliage can be pressed to form plant materials with natural curve. Pressing is done by placing plant materials between layers of an absorbent paper material and applying weight or pressure for at least 5 to 10 days or until the plants are dried (Musgrove, 1998) Smith and Laschkewitsch (1998) stated that pressing is the very easy way to preserve flowers although the colour is lost and flowers become flat like aster, butter cup, zinnia, pansy and geranium. Winter (1998) reported that flowers like buttercups, daffodils, marigolds, pansies and Queen Anne s lace are suitable for pressing. Flowers can be pressed by placing them between layers of an absorbent material like newspaper, old telephone directories or catalogs. Absorbent facial tissues can be placed on the pages to help the flowers dry faster. It can be stacked in several layers deep without overlapping and boards can be placed beneath and on top of the stack. Drying room should be warm and dry. Anon. (2001) suggested that press drying time depending on the flower size and moisture content takes generally 1-3 weeks. Most flowers and leaves are suitable for pressing except those with bulky centers such as succulents, odd shaped flowers such as daffodils need to be cut in half and opened out before pressing, thick flowers like

32 chrysanthemum needs to have the calyx reduced in thickness, single petals can also be dried and reassembled when making craft. Dana and Lerner (2002) reported that pressing of plant materials takes about 3 weeks, it is popular for small flowers, ferns and autumn leaves. Supriya (2004) has reported that flowers suitable for press drying are pansy, coral-bells, lily, hardy geranium and bell flower. Most flowers and leaves are suitable for pressing, except those with bulky centers or fleshy leaves, such as succulents. Odd shaped flowers such as daffodils need to be cut in half and opened out before pressing.single petals can also be dried, and reassembled when making the picture (Dry, 2006) White et al. (2007) reported that colours and forms of many leaves and some flowers can be preserved by placing them between layers of news paper or pages of old phone book, foliages (ivy) dry within 1 week and flowers (gerbera and chrysanthemum) in 2 weeks. Pressing flowers can be very gratifying in itself and will add to the enjoyment of creating a finished pressed flower piece. Microwave flower pressing was found to be the best method as it allows greater air circulation (Anon., 2008a). Singh and Kumar (2008) stated that African violets, larkspur, pansies and ferns preserve well through this pressing technique, flowers especially flat are called face flowers like daisies, pansies, asters, cosmos and zinnias can be press dried Glycerinisation Paparozzi and Mc callister (1988) conducted trials on glycerol and microwave preservation of annual statice and concluded that fresh and cut statice stems up to 34 cm long preserved well by soaking in a 1:2 or 1:3 glycerol: water solution for 48 hours followed by microwave drying for 1 medium high (34º C). Similarly

33 Padmavathamma (1999) observed the beneficial effect of glycerol pre- drying treatment in statice flower. Anon. (1998) reported that branches are allowed to absorb the solution for 2 to 6 weeks depending on the texture and size of the leaves and branches and also recommended some leaves like Elaegnus pungens, beech (Fagus grandiflora), ivy, magnolia, oaks, oleander (Nerium oleander) and pittosporum. Martha (1995) reported that glycerin preservation keeps the leaves soft and pliable for easier handling and less shedding. Smith and Laschkewitsch (1998) stated that plant materials suitable for glycerin infusion include woody species such as magnolia, oak and eucalyptus. Day (2000) reported that glycerinization holds good for foliages, leaves should absorb enough liquid to be soft and pliable and it also depends on the leaf, a hard, thick magnolia leaf takes longer time than a soft thin maple leaf. Anon. (2001) reported that this method is most suitable for foliage than flowers but certain flowers like Bells of Ireland, statice, hydrangeas, lady s mantle, narcissus, rose hips can be used. Some plants take 30 hrs while other may take 2-3 months should not place for longer days causes bleeding from the leaves. Dana and Lerner (2002) reported that glycerinisation is best for preserving small leafy tree branches, glycerin will enter the leaves and turn brown, average time taken for drying is 2-3 weeks, best results were reported when this method is used during summer season when absorption is rapid within 2-6 days of immersion the leaves will be soft and pliable. Anon. (2004) stated that glycerin is more suitable for foliages than flowers like oak, ivy, magnolia, beech etc. Dubois and Joyce (2005) reported that usually a solution of 10 to 30 per cent glycerol in water is satisfactory. Actively growing foliage gives the best results. Species

34 which normally undergo cyclic growth patterns (for example, leucodendrons) may only take up the glycerol solution if picked during a growth flush (usually mid-summer). Bale (2006) reported that glycerin preserves foliages by replacing the natural moisture present in the leaf with glycerin and maintains the leaf form, texture and colour,also reported boxwood and croton takes (10-15days), ivy (5-10 days ), oak (several days ) when submerged in glycerin. Trinklein (2006) reported that plant species such as anthurium, aspidistra, beech, bells of ireland, cotoneaster, crabapple, dracaena, english ivy, eucalyptus, galax, juniper, lemon, magnolia, mountain ash, maples, myrtle, oaks, orange holly grape, peony, periwinkle, purple leaf plum, poplar, statice, sweet gum, ti plant and weigela can be treated with glycerin. White et al. (2007) reported that treating foliages with glycerin yield unique results, although stem and leaves turn brown in this process, they will remain flexible and pliable indefinitely. They also reported two methods glycerin uptake, average time taken for this treatment is 2-3 weeks and highly suitable for foliages of magnolia, ligustrum and broad leaved evergreens, next is full dip method, in this the plant material absorb glycerin through the leaf surface and can be submerged in the solution done with ferns and single leaves of poplar and palmetto. Singh and Kumar (2008) suggested leaves like camellia, ivy, maiden hair fern and eucalyptus are all good candidates for drying with glycerin Floral crafts Bhutani (1993) reported that floral crafts viz., greeting cards, wall hanging floral designs, landscape calendar and such other creative displays could be made by embossing the press dried flower with foliage on various background such as velvet paper, Linen or silk.

35 Datta (1999) suggested that dehydrated flower and foliage can be used for designing distinctive and artistic greeting cards, wall plates, landscaped and interior decorative items with dry flower sealed in glass container. Raghupathy et al. (2000) suggested that dried plant material can be used in wreaths, topiaries, swags, collages, flower pictures, cards and covers innovate items such as candle stand, table lamps, picture frames, floral jewellery, mirror decorative and arrangement in glass containers. Dried or preserved plant materials complement any home decor in both formal and informal arrangements. They will last almost indefinitely if carefully done and require very little care. Flower arrangements, wreaths, pressed pictures, potpourri and wall hangings are just some of the creative possibilities with preserved plant materials (Dana and Lerner, 2002). Dried and press dried flowers and foliage can be utilized for making decorative floral craft items for home decoration and also for commercial exploitation (Paul and Shylla, 2002) White et al. (2007) suggested that dried materials could be used to enhancevases, baskets, plaques, shadow boxes and fresh flower arrangements. They also may be used as wall decorations, in wreaths, corsages and as decorations on gift boxes. Brandy snifters, candy jars, terrariums and other glassware provide dramatic displays for dried materials. Patil and Singh (2008) reported that dried flowers may be arranged in dry vases just as the fresh cut flowers are arranged. They can be arranged in bouquets or wall displays after fastening them to decorative bands Storage of dried flowers Dried materials should be stored in a dark, dry airtight container. A layer of tissue paper should be placed between flowers to reduce breakage. Spaying the dried flowers with a clear plastic will prevent them from absorbing water during humid periods and prevent dust from sticking and discolouring the petals (Gouin, 1994).

36 Bhutani (1995) suggested that the embedded flowers and foliage after dehydration should be taken out by tilting the container in order to remove the desiccant over and around the flowers or other plant material. The dried plant material can be then stored in the desiccators or glass jars or plastic jars in which silica gel crystals kept at the bottom to prevent them from spoilage and for their further utilization. Bull (1997) claimed that dried flowers could be stored in a covered wicker box or card board box with holes on top and sides. The materials should not be stored in plastic covers and boxes. The flowers such as larkspur, Hydrangea or sweet Anni could be made durable by using a hair spray over them and wrapped loosely with tissue paper or newspaper and laid flat in the container kept in a cool dry place. Yan (1999) suggested to wrap the dry flowers in newspaper and to place them in a cardboard box. He also suggested that the box should not be stored in an unusually damp or very dry place. Singh et al. (2003) reported that moisture content in dried flowers of Zinnia linearis influences the flower quality and longevity. Excessive drying results into petal shedding during handling and moisture content below 8 percent results in petal shedding. A range of 8 to 11.5 percent moisture content in the dried flowers provided optimum drying with good quality, firmness showed good keeping quality above six months. Dried flowers absorb atmospheric moisture and lose their shape. Therefore, they should be stored immediately in moisture proof containers like glass desiccators, tin boxes, carton, wrapped with wax paper which can be protected from light and direct sunlight to preserve the colour (Datta, 2004). Trinklein (2006) recommended various control measures against the household insects which move into the boxes during storage. The container should be tightly sealed to prevent the invasions. And the flowers which tend to fade may be lightly tinted with aerosol paints, dyes for more durable colour.

37 Dried materials are packed in closed boxes, sealed plastic bags containing mothballs. Silica gel packets can be kept in the boxes to absorb any moisture in the air and precautionary measures should be taken to prevent fire hazards since the dried plant materials are highly flammable (White et al., 2007). Wrap small bunches of the flower in tissue paper and tie the tissue closed with a little string or raffia. Floral boxes are best suited for storing dried flowers. They can even be well packed in poly bags, window box or in a sachet. They are stored in airtight container to prevent it from moisture and sunlight (Anon., 2008b).

38

39 III MATERIAL AND METHODS The present research topic entitled Studies on dehydration of Dendrobium orchid flowers were carried out during at the Division of Post harvest technology, Indian Institute of Horticultural Research, Hesaraghatta, Bengaluru. Details of the location, material and methods used under different experiments are presented below. 3.1 Location of the experiments The experiments were conducted at the cut flower laboratory of the Post harvest technology division which is located at an elevation of 930 meter from mean sea level and between North latitude and 77º 45 East longitude. Data on laboratory temperature and relative humidity during experimentation are presented in appendix Material used Three varieties of Dendrobium orchid flowers, hot air oven, sand, silica gel, plastic trays, threads, camel hair brush, air tight plastic container, black cloth, polyethylene covers and electronic digital balance. 3.3 Sources of flowers Flowers for the experiment were collected from a commercial orchid grower of Chapparmane village, Sirsi. 3.4 Varieties In experiment- I three Dendrobium orchid varieties were used. Botanical description of the varieties viz., Sonia- 17, Emma White and Caesar Red are as follows and given in plate 1. Sonia 17: Flowers of var. Sonia- 17(V 1 ) were of white and purple. Sepals were creamy white with purple markings. Flower spikes were of florets. Petals were purple in colour. One of the modified petal is called labellum which has light purple with cream colour showing feathery outgrowth in lines (Plate 1 a ).

40 Sonia-17 Emma White Caesar Red Plate 1. Fresh flowers of Dendrobium orchid varieties

41 Emma white: Flowers of var. Emma White (V 2 ) used were of creamy white sepals, petals and labellum with 7 florets per spike. Petals are larger than sepals. Lips have feathery longitudinal sections (Plate 1 b). Caesar Red: Petals, sepals and labellum colour of var. Caesar Red (V 3 ) were of dark magenta (Plate 1 c). 3.5 Harvesting The flower spikes of above mentioned Dendrobium orchid varieties were harvested with sharp secateur in single cut between 4.30 p. m to 6.30 p.m. Immediately after the harvest, the cut ends of these spikes were inserted in a voil containing water. Ten spikes were placed in a polyethylene sleeves of 150 gauge thickness and with vents. These sleeves containing flower spikes were packed in the corrugated fibre board boxes and were transported over night by road to the laboratory. 3.6 Stage of harvest Three harvest stages used under the experiment are listed below with the description and photographs in Plate- 2. (a) Half opened stage: Petals and sepals were in vertical position showing greenish (Plate 2 a). (b) ¾ th opened stage: Showing 75 % of the floret opened in angular form with more prominent greenish exhibiting growth on the labellum (Plate 2 b). (c) Fully opened stage: The tepals were expanded fully in the butterfly pattern with feathery outgrowth on the labellum (Plate 2 c). 3.7 Experimental details Experiment -1: Evaluation of Dendrobium orchid varieties for suitability to dried flowers Varietal evaluation for dried flower suitability was carried out with three Dendrobium orchid varieties viz., Sonia- 17, Emma White and Caesar Red. The flowers

42 Half opened ¾ th opened Fully opened Plate 2. Harvest stage of Dendrobium orchid var. Sonia-17

43 were sorted out for any mechanical or pest damage. Only good samples were selected for conducting the experiment. Fresh weight of the flowers of each of these three varieties was recorded. Later it was subjected to silica gel embedded drying in hot air oven at 40 ºC for 48 hours. A layer of 1 cm depth of desiccant was spread over the base of the drying tray. Following way flowers were embedded in the silica gel. Flowers were placed in upright position over the embedding medium (silica gel). Flowers were fully covered by gently pouring the silica gel (Plate 3). Constant weights of the two consequent readings indicated the end of the drying. At this point of drying trays containing flowers embedded in silica gel were taken out from the oven and were kept for setting. After two to three hours of setting under ambient condition, dried flowers were taken out from the embedding medium by slanting the tray to drop the medium to separate the flowers from embedding medium for easy picking of flowers. If any white dust remained, it was removed carefully by brushing with a soft brush. Treatment details Treatments : Three varieties (V 1 : Sonia- 17, V 2: Emma White and V 3 : Caesar Red ) Design : CRD Replications : Eight Observations recorded: Following observations were recorded under this experiment. 1. Fresh Weight Fresh weight of all the flower samples before treatment was recorded and expressed as gram (g) per flower. 2. Dry weight Dry weight of all the flower samples after drying was recorded and expressed as gram (g) per flower.

44 Plate 3. Embedding of orchid flowers in silica gel Plate 4: Measurement of Flexibility

45 3. Per cent moisture loss Difference between fresh weight and dry weight of the flower was expressed in percentage. Fresh weight dry weight Moisture loss (%) =.. X 100 Fresh weight 4. Drying rate: Drying rate was calculated by using the following formula 5. Flexibility Amount of moisture removed (g) Drying rate =... Time taken x dry weight (g) Expressed as g of water removed / hour (g/h) Flexibility of dried flowers of Dendrobium orchid was measured by holding the flowers at 90º and bending towards 0º and the angle of breakage is expressed as flexibility (Plate 4). The degree of breakage is rated as follows: 41-50º Very good 31-40º Good 21-30º Average 11-20º Poor 0-10º Very poor 6. Fresh and dried flower colour Fresh and dried flower colour for each sample was evaluated by matching with the RHS Colour Chart (RHS CC; The Royal Horticultural Society, UK). Fresh and dried flower colour of petal, sepal and labellum was also measured with colourimeter CR- 10 (Minolta chroma instrument, Osaka, Japan) by holding the fresh and dried flowers directly on sensing head (Plate 5). Colours were expressed according to the

46 Commision International de l Eclairagea (CIE) L* a* b * system. The fresh and dried flower samples from each replicate were measured for L* a* b*. Note: L: describes lightness (L* = 0 for black, L*=100 for white ) a: describes colour intensity in red (a* > 0) or in green (a* < 0) b : describes colour intensity in yellow (b * > 0) or in blue (b * < 0 ) 7. Flower diameter The flower diameter of each replicate samples were recorded in centimeters from 2 sides of the flowers and their mean values were calculated for flower diameter. 8. Size of petal, sepal and labellum Length and breadth of petal, sepal and labellum of both fresh and dried flowers were measured in centimeter. The mean values of these parameters are presented as their size (cm). 9. Quality display Quality parameters like colour, texture and shape of dried flowers of Dendrobium orchid obtained under the experiment were assessed by means of sensory evaluation. A panel of members evaluated the dried flowers by scoring on 25 point scale. Viz., Very good, good, average, poor and very poor Experiment -2: Determination of an optimum harvest stage for quality dried flowers Based on the results of the experiment 1, Dendrobium orchid var. Sonia- 17 was selected for dried flower qualities. Further to achieve better qualities of dried flowers through harvest stages viz., Half opened, ¾ th opened and fully opened flowers, the experiment was carried out. Photographs of these three harvest stages of flowers of Dendrobium orchid var. Sonia- 17 are shown in plate 2. The flowers of each harvest stage were embedded as described in experiment -1.

47 Treatment details: Harvesting stage : Three S 1: Half opened, S 2 : ¾ th opened and S 3 : Fully opened Design : CRD Replications : Eight Observations recorded Observations recorded in this experiment were same as explained in the experiment Experiment-3: Effect of embedding media, drying methods and positioning on dried flowers qualities Based on the results of the experiment 2, the optimum harvest stage i.e. ¾ th opened stage was selected for better dried flower quality viz., size, shape, colour, texture under this experiment. The experiment was carried out with different embedding media viz., Silica gel, Sand and combination of Silica gel and sand in two methods of positioning viz., face up and face down at two different drying methods (Hot air oven and ambient). The flowers were embedded in different desiccants by placing them in both face up and face down position similar to as mentioned in experiment- 1 (Plate 3). The procedure for drying flowers in ambient condition is similar to as explained in the experiment- 1. The flowers were embedded in three different embedding media by placing the flowers both in upward and downward position. After placing, the florets slowly sift the embedding media around the flower until it is covered fully. A clean plastic tray was used to cover the embedded flowers, which was made then air tight to prevent the entry of ambient moisture (Plate 6). Factor A Embedding media (E) E 1 : Silica gel E 2 : Sand E 3 : Silica gel and sand : Three

48 Plate 5. Colourimeter Plate 6. Embedding of orchid flowers in silica gel under ambient condition

49 Factor B Drying methods (D) D 1 : Hot air oven D 2 : Ambient condition Factor C Positioning (P) P 1 : Face Up P 2 : Face Down E (3) x D (2) x P(2) Design Replications : Two : Two : 12 treatments : Factorial CRD : Three Number of flowers per replication : Five Total number of treatments 1. E 1 D 1 P 1 7. E 2 D 2 P 1 2. E 1 D 1 P 2 8. E 2 D 2 P 2 3. E 1 D 2 P 1 9. E 3 D 1 P1 4. E 1 D 2 P 2 10.E 3 D 1 P 2 5. E 2 D 1 P E 3 D 2 P 1 6. E 2 D 1 P E 3 D 2 P 2 Observations recoded 1. Dry weight Dry weight of all the flower samples after drying was recorded and expressed as gram (g) per flower. 2. Per cent moisture loss Difference between fresh weight and dry weight of the flower was expressed in percentage.

50 Fresh weight dry weight Moisture loss (%) =.. X 100 Fresh weight 3. Drying rate: Drying rate was calculated by using the following formula Amount of moisture removed (g) Drying rate =... Time taken x dry weight (g) Expressed as g of water removed / hour (g/h) 4. Flexibility Flexibility of dried flowers of Dendrobium orchid was measured by holding the flowers at 90º and bending towards 0º and the angle of breakage is expressed as flexibility. The degree of breakage is rated as follows: 41-50º Very good 31-40º Good 21-30º Average 11-20º Poor 0-10º Very poor 5. Flower diameter The flower diameter of each replicate samples were recorded in centimeters from 2 sides of the flowers and their mean values were calculated for flower diameter. 6. Size of petal, sepal and labellum Length and breadth of petal, sepal and labellum of both fresh and dried flowers were measured in centimeter. The mean values of these parameters are presented as their size (cm).

51 7. Quality display Quality parameters like colour, texture and shape of dried flowers of Dendrobium orchid var. Sonia-17 obtained under the experiment were assessed by means of sensory evaluation. A panel of members evaluated the dried flowers by scoring on 25 point scale. Viz., Very good, good, average, poor and very poor Experiment -4: Evaluation of shelf life of dried flowers of Dendrobium orchid var. Sonia-17 Dried flowers of Dendrobium orchid var. Sonia 17 were evaluated for shelf life. The packages used were plastic container, Polyethylene and without any package (open) under two storage conditions viz., dark and light. One set of dried flowers were packed in different packages were covered with black cloth (Plate 7 a) and another set of dried flowers in different packages were kept open (Plate 7 b). The shelf life of these dried flowers was evaluated at monthly interval. Factor A Package (Pk) : Three Pk 1 : Plastic container Pk 2 : Polyethylene Pk 3 : No package (without package) Factor B Storage (Sc) : Two Sc 1 : Dark Sc 2 : light Design : Factorial CRD Replications : Four Number of flowers per replication : Five Pk (3) x Sc (2) : 6 treatments

52 a b Plate 7. Packing and storage of dried flowers of Dendrobium orchid var. Sonia-17 under a. Dark and b. Light 3

53 Treatments: 1. Pk 1 Sc 1 4. Pk 2 Sc 2 2. Pk 1 Sc 2 5. Pk 3 Sc 2 3. Pk 2 Sc 1 6. Pk 3 Sc 1 Observations recorded 1. Quality display Quality parameters like colour, texture and shape of dried flowers of Dendrobium orchid var. Sonia-17 obtained under the experiment were assessed by means of sensory evaluation. A panel of members evaluated the dried flowers by scoring on 25 point scale. Viz., Very good, good, average, poor and very poor. 2. Shelf life Shelf life of dried flowers of Dendrobium orchid var. Sonia-17 was evaluated by packing the dried flowers in an air tight plastic container, 300 gauge thick polyethylene covers and without package (open) at monthly intervals for dried flower colour, texture, shape and flexibility Experiment -5: Product diversification of Dendrobium orchid dried flowers of var. Sonia-17 Dried orchid flowers obtained from the experiments under the study were used in flower arrangement in acrylic package, floral arrangement in bamboo basket and dried labellum in greeting card for the product diversification and value addition (Plate 13). These prepared dried flower products were evaluated for their acceptability. Design : CRD Treatments : 3 Replications/ treatments : 8

54 Observations recorded Quality display Quality parameters like colour, texture, shape and overall acceptability of dried flowers of Dendrobium orchid var. Sonia-17 obtained under the experiment were assessed by means of sensory evaluation. A panel of members evaluated the dried flowers by scoring on 25 point scale. Viz., Very good, good, average, poor and very poor. Proforma for Sensory Score on quality display of dried Dendrobium orchid flowers Using the scale on display, would you please rate each of the sample by placing a number in appropriate column. Sl. No. Code Colour (25) Shape (25) Texture (25) Remarks Total Very Good : Good : Average : Poor : 6-10 Very Poor : 0-5 Signature :... Name :...

55 Statistical Analysis Experimental data obtained under the experiment 1, 2 and 5 was completely randomized design and Experiment 3 and 4 was factorial CRD. Data were analyzed statistically at the computer centre, University of Agricultural Sciences, Gandhi Krishi Vignana Kendra, Bangalore. The design used for the analysis was factorial completely randomized design and completely randomized design. The limit of probability fixed for the level of significance was p= 0.05.

56

57 IV EXPERIMENTAL RESULTS The results obtained in the present research topic entitled Studies on dehydration of Dendrobium orchid flowers during the year at the Division of Post harvest technology, Indian Institute of Horticultural Research, Hesaraghatta, Bengaluru are presented in the this chapter. 4.1 Experiment -1: Evaluation of Dendrobium orchid varieties for suitability to dried flowers Dendrobium orchid flowers of three varieties viz., Sonia-17, Emma White and Caesar Red were evaluated for dried flower qualities in silica gel embedded hot air oven (plate 8). Data on parameters such as fresh weight, dry weight, per cent moisture loss, drying rate, flexibility, flower diameter, petal, sepal and labellum size colour, texture and shape is presented in tables Fresh weight of flowers Fresh weight of flowers of three varieties of Dendrobium orchids recorded is presented in table 1 Significant differences were observed in the fresh weight of three varieties of Dendrobium orchid flowers. Dendrobium orchid var. Sonia-17 had maximum fresh weight of 2.86 g followed by 1.78 g in var. Caesar Red flowers. Minimum fresh weight of 1.45 g was recorded in var. Emma white Dry weight of flowers Data on the dry weight of flowers of three varieties of Dendrobium orchids was recorded and presented in table 1. Significant differences were observed among the dry weights of flowers of Dendrobium orchid varieties evaluated, highest dry weight of 0.31 g/ flower was

58 Table 1. Fresh and dry weight of flowers of Dendrobium orchid varieties Varieties Fresh weight (g) Dry weight(g) Sonia Emma White Caesar Red Mean SEM± CD F- test * * Table 2. Per cent moisture loss, drying rate of fresh flowers during drying and flexibility of dried flowers of Dendrobium orchid varieties Varieties Moisture loss (%) Drying rate (g/h) Flexibility(º) Sonia Emma White Caesar Red Mean SEM± CD F- test * * *

59 a b Plate 8. Dried flowers of Dendrobium orchid varieties a. Sonia-17, b. Emma white and c. Caesar Red c

60 recorded with Dendrobium orchid var. Sonia- 17 followed by 0.24 g/ flower with var. Caesar Red. Least dry weight of 0.17 g/ flower was recorded in var. Emma White Per cent moisture loss Data with respect to the per cent moisture loss of all three varieties of Dendrobium orchid flowers was recorded and presented in table 2. Significant differences were observed on per cent moisture loss during dehydration of Dendrobium orchid flowers. Maximum moisture loss of per cent was recorded in the var. Sonia-17 followed by per cent moisture loss in var. Emma white. Least per cent moisture loss of was recorded in var. Caesar Red Drying rate Data pertaining to drying rate of three varieties of Dendrobium orchid flowers was recorded and presented in table 2. Significant differences were observed among the flower drying rate of the varieties evaluated. Maximum flower drying rate of 1.75 g of moisture loss/ h was recorded in var. Sonia-17 followed by a drying rate of 1.51 g moisture loss / h in var. Emma white. Minimum drying rate of 1.41 g moisture loss/ h was obtained in var. Caesar Red Dried flower flexibility Significant differences were observed in flexibility of dried flowers of Dendrobium orchid varieties and data are presented in table 2. The angle of petal breakage was maximum in var. Sonia-17 (42º.00) followed by 32º.00 angle with dried petals of var. Caesar Red. Less degree (22º.00) of petal breakage indicated poor flexibility with var. Emma white.

61 4.1.6 Fresh and dried flower colour Colour readings of L*a* b* on fresh and dried flowers of each varieties was recorded and are presented in tables 3 and 4. Petal, sepal and labellum colour of fresh and dried flowers of Dendrobium orchid varied significantly among the varieties. Maximum brightness of 80.46, and white colour respectively was obtained for petal, sepal and labellum in fresh flowers of var. Emma White followed by 40.30, and L* values of sepal petal and labellum respectively of fresh flowers of var. Sonia-17. Brightness was least (22.34, and 27.10) with labellum, sepal and petal respectively in fresh flowers of var. Caesar Red. Fresh flower colour of var. Caesar Red sepals showed higher intensity of red followed by red colour intensity of fresh flowers of var. Sonia-17 petals. Red colour intensity of labellum of flowers of var. Caesar Red was least (24.68). Intensity of green colour of sepals was higher (-2.76) followed by intensity of green colour (-4.28) of petals of var. Emma White fresh flowers. Intensity of green colour labellum was least (-5.88) in var. Emma White. Intensity of blue colour was higher (- 1.80) in labellum of var. Caesar Red followed by its petal blue colour (-6.26). Least blue colour intensity of was observed in flowers of var. Sonia-17. Higher value of L* for petals followed by L* values of for labellum of dried flowers of Dendrobium orchid var. Emma White indicated the higher whiteness. Least L* value of was observed in labellum colour of dried flowers of var. Caesar Red. Higher a* value of obtained indicated the higher intensity of red colour of petals of dried flowers of var. Sonia-17 followed by a* value for red colour of petals of var. Caesar Red dried flowers. Least red colour intensity of was obtained for labellum of var. Caesar Red. Higher value of b* of labellum indicated higher intensity of yellow followed by b* for petals of var. Emma White. Least value of b* for yellow colour was obtained only in sepals of dried flowers of var. Emma White only dried flowers of var. Emma White showed value for green colour (a* values of -4.00, and -4.38) for petal, sepal and labellum respectively.

62 Table 3. Colour (L* a* b*) of fresh flowers of Dendrobium orchid varieties Varieties Petal Sepal Labellum L* a* b* L* a* b* L* a* b* V V V Mean SEM CD F-test * * * * * * * * * V 1 : Sonia- 17, V 2 : Emma White and V 3: Caesar Red Table 4. Colour (L* a* b*) of dried flowers of Dendrobium orchid varieties Varieties Petal Sepal Labellum L* a* b* L* a* b* L* a* b* V V V Mean SEM CD F-test * * * * * * * * * V 1 :. Sonia- 17, V 2 : Emma White and V 3: Caesar Red

63 Based on the RHS Colour Chart (RHS CC; The Royal Horticultural Society, UK) the following results were obtained for fresh flowers of Dendrobium orchid varieties. Dendrobium orchid var. Sonia-17 was matching with Red purple group (Petal and labellum were of Red - Purple 71A and sepal were of Red - Purple 78A), petal and sepal was matching with White group and labellum were of Yellow green 154c for var. Emma White whereas Red purple group for var. Caesar Red (Red purple 60A). Dendrobium orchid var. Sonia-17 was matching with Purple group (Purple 77A) for petal colour and Violet group (Violet 60A) for labelllum of dried flowers, colour of var. Emma white was matching with Yellow green group (Yellow green 154D) for labellum and Yellow group for petal and sepal of dried flowers, whereas the flower colour of var. Caesar Red was Purple (Purple 71A for petal and 79B for labellum). Results of sensory evaluation on dried flower colour of Dendrobium orchid varieties evaluated was recorded and presented in table 5. Maximum sensory score of was recorded in var. Sonia -17 and followed by sensory score to var. Caesar Red. Least sensory score of was given to var. Emma White Dried flower texture Sensory score of dried flower texture of Dendrobium orchid varieties are presented in table- 5. Significant differences were observed among the dried flower texture of Dendrobium orchid varieties. Maximum sensory score of was given to the dried flower texture of Dendrobium orchid var. Sonia -17 followed by a sensory score of given to the dried flower texture of var. Caesar Red. Minimum sensory score of were obtained in var. Emma White.

64 Table 5. Sensory score of colour, texture and shape of Dendrobium orchid varieties Varieties Colour Texture Shape Sonia Emma White Caesar Red Mean SEM CD F-test * * * Very Good : Good : Average : Poor : 6-10 Very Poor : 0-5 Table 6. Diameter of fresh and dried flowers of Dendrobium orchid varieties Varieties Fresh flower diameter (cm) Dried flower diameter (cm) Sonia Emma White Caesar Red Mean SEM ± CD F-test * *

65 4.1.8 Dried flower shape Score given by the panel members during the sensory evaluation of Dendrobium orchid dried flowers for shape is given in table 5. Shape of dried flowers differed significantly among the varieties. Maximum sensory score of was given to the var. Sonia- 17 for the dried flower shape followed by a sensory score of for the var. Emma White which was on par with var. Caesar Red dried flower sensory score (21.20) Fresh and dried flower diameter Data regarding fresh and dried flower diameter are given in tables (6, 7 and 8). Significant differences were observed in fresh flower diameter of Dendrobium orchid varieties evaluated. Fresh flower diameter of 6.85 cm was recorded maximum with var. Caesar Red. Minimum diameter of 6.67 cm was recorded with fresh flowers of var. Emma White (Table 6). Dried flower diameter of Dendrobium orchid varieties varied significantly. Maximum dried flower diameter of 6.76 cm was recorded with Dendrobium orchid var. Caesar Red. Minimum diameter of 6.60 cm was recorded in var. Emma White dried flowers. Petal, sepal and labellum size of fresh flowers was found significant. Maximum petal size of 3.16 cm of was recorded with fresh flowers of Dendrobium orchid var. Sonia -17. Minimum petal size of 3.00 cm was observed in fresh flowers of var. Caesar Red and was on par with fresh flower petal size of var. Emma White. Maximum sepal size of 2.59 cm was recorded with fresh flowers of var. Sonia-17 whereas minimum sepal size of 2.25 cm was recorded in fresh flowers of var. Emma White. Maximum labellum size was recorded with fresh flowers of var. Sonia-17 flowers (2.21 cm) which was on par with labellum size of var. Emma White and minimum labellum size of 2.01 cm in var. Caesar Red fresh flowers.

66 Table 7. Fresh flower petal, sepal and labellum size of Dendrobium orchid varieties Varieties Petal (cm) Sepal (cm) Labellum (cm) Sonia Emma White Caesar Red Mean SEM ± CD F-test * * * Table 8. Dried flower petal, sepal and labellum size of Dendrobium orchid varieties Varieties Petal (cm) Sepal (cm) Labellum (cm) Sonia Emma White Caesar Red Mean SEM ± CD F-test * * *

67 Dried flower size of petal, sepal and labellum was found significant (table 8) among the Dendrobium orchid varieties evaluated. Dendrobium orchid var. Sonia-17 had a maximum petal, sepal and labellum size of 2.98 cm, 2.41 cm and 2.06 cm respectively followed by petal, sepal and labellum size of 2.89 cm, 2.14 cm and 2.04 cm. Minimum petal, sepal and labellum size was recorded in var. Caesar Red (2.76 cm, 2.09 cm and 1.60 cm respectively). 4.2 Experiment -2: Determination of optimum harvest stage for improved quality of dried flowers Three harvest stage of Dendrobium orchid var. Sonia-17 viz., half opened, ¾ th opened and fully opened flowers were evaluated for dried flower qualities such as fresh weight, dry weight, drying rate, per cent moisture loss, flower diameter, petal, sepal and labellum size, flexibility, colour, texture and shape (Plate 9). Data is presented in tables Fresh weight of flowers Data on fresh weight of three harvest stages of Dendrobium orchid var. Sonia-17 flowers was found significant and are presented in table 9. Maximum fresh weight was recorded (2.80 g) in fully opened harvest stage flowers followed by fresh weight of 2.52 g in ¾ th opened harvest stage flowers. Minimum fresh weight of 2.23 g of fresh weight was recorded in the half opened harvest stage flowers Dry weight of flowers Data on dry weight of different stages of harvest of Dendrobium orchid var. Sonia-17 flowers was found significant and are presented in table 9. Maximum dry weight of 0.31 g was recorded in fully opened harvest stage dried flowers followed by a dry weight of 0.26 g in ¾ th opened harvest stage dried flowers. Least dry weight of 0.24 g was recorded in half opened harvest stage dried flowers.

68 Table 9. Effect of harvest stages on fresh and dry weight of flowers of Dendrobium orchid var. Sonia-17 Harvest Stages Fresh weight (g) Dry weight (g) Half opened ¾ th opened Fully opened Mean SEM± CD F-test * * Table 10. Effect of harvest stages on per cent moisture loss, drying rate of fresh flowers and flexibility of dried flowers of Dendrobium orchid var. Sonia 17 Harvest stages Moisture loss (%) Drying rate (g/h) Flexibility(º) Half opened ¾ th opened Fully opened Mean SEM± CD F-test * * *

69 Half opened ¾ th opened Fully opened Plate 9. Dried flowers of Dendrobium orchid var. Sonia 17

70 4.2.3 Per cent moisture loss Data on per cent moisture loss varied significantly among the harvest stages of Dendrobium orchid var. Sonia-17 as influenced by different harvest stages of Dendrobium orchid flowers are presented in table 10. Maximum of per cent loss of moisture was observed in ¾ th opened harvest stage flowers followed by moisture loss of per cent in fully opened harvest stage flowers. Minimum of per cent moisture loss was recorded in half opened harvest stage flowers Drying rate Data pertaining to the drying rate of Dendrobium orchid var. Sonia-17 flowers as influenced by the different harvest stages was found significant and are presented in table 10. Maximum drying rate of 1.95 g/h was recorded in ¾ th opened harvest stage flowers followed by drying rate of 1.62 g/h in fully opened harvest stage flowers. Minimum drying rate of 1.5 g/h was recorded in half opened harvest stage flowers Dried flower flexibility Significant differences were observed in flexibility of dried flowers of different harvest stages of Dendrobium orchid var. Sonia-17 and data is presented in table 10. Harvest stage of ¾ th opened flowers showed a very good flexibility of º followed by flexibility of 42.30º in fully opened harvest stage flowers. Lower degree of 16.90º was obtained in half opened harvest stage of dried flowers Fresh and dried flower colour Colour readings of L*a* b* on fresh and dried flowers of different harvest stages of Dendrobium orchid var. Sonia-17 are given in tables 11 and 12. Petal, sepal and labellum colour of three harvest stages of both fresh and dried flowers of Dendrobium orchid var. Sonia-17 were found significant.

71 Table 11. Colour (L*a*b*) of different harvest stages of fresh flowers of Dendrobium orchid var. Sonia-17 Harvest stages Petal Sepal Labellum L* a* b* L* a* b* L* a* b* S S S Mean SEM CD F-test * * * * * * * * * S 1: half opened, S 2 : ¾ th opened and S 3 : fully opened Table 12. Colour (L*a*b*) of different harvest stages of dried flowers of Dendrobium orchid var. Sonia-17 Harvest stages Petal Sepal Labellum L* a* b* L* a* b* L* a* 謀 * S S S Mean SEM CD F-test * * * * * * * * * S 1: half opened, S 2 : ¾ th opened and S 3 : fully opened

72 Maximum brightness of and respectively was obtained for sepal and labellum in fresh flowers of half opened harvest stage followed by L* values of and respectively was obtained for sepal and labellum in fresh flowers of fully opened harvest stage. Brightness was least (32.96 and respectively) for sepal and labellum of fresh flowers of ¾ th opened harvest stage whereas maximum brightness of was observed for petal in fresh flowers of ¾ th opened harvest stage followed by L* (25.25) in fresh flowers of half opened harvest stage. Fresh flowers of fully opened harvest stage showed higher intensity of and red colour for petal and labellum respectively followed by a* values of and for petal and labellum respectively with the fresh flowers of half opened harvest stage. Higher intensity of red colour was observed in fresh flowers of fully opened harvest stage followed by red colour intensity for sepals of ¾ th opened harvest stage whereas half opened harvest stage showed a least intensity of red colour for sepals. Intensity of blue colour was higher ( and -5.58) for petal and labellum respectively with the fresh flowers of ¾ th opened harvest stage followed by intensity of and blue colour for petal and labellum respectively in the fresh flowers of half opened harvest stage. Blue colour intensity of was found maximum for sepals of fresh flowers of half opened harvest stage followed by blue colour intensity of with the fresh flowers of ¾ th opened harvest stage. Maximum brightness of 43.16, and was recorded for sepal, petal and labellum respectively in dried flowers of fully opened harvest stage followed by 36.98, and of L* values for sepal, labellum and petal of dried flowers of ¾ th opened harvest stage. Higher intensity of red colour (34.80 and 29.66) was observed for sepal and labellum of dried flowers of ¾ th opened harvest stage followed by a* values of and for sepal and labellum in dried flowers of half opened harvest stage. Dried flowers

73 of ¾ th opened harvest stage showed a higher intensity of red colour for petals followed by a* value for petals of fully opened harvest stage dried flowers. Intensity of blue colour was higher (-7.38 and ) for labellum and sepal of fully opened harvest stage dried flowers followed by blue colour intensity of and was observed in dried flowers of half opened harvest stage. Intensity of blue colour of petals was higher (-11.50) in dried flowers of half opened harvest stage followed by intensity of blue colour in dried flowers of fully opened harvest stage whereas intensity of blue colour was least (-14.8) in dried flowers of ¾ th opened harvest stage. Based on the RHS Colour Chart (RHS CC; The Royal Horticultural Society, UK) Red purple colour was dominant in fresh flowers of different harvest stage of Dendrobium orchid var. Sonia-17 where in Red Purple 71A for petal and labellum and Red Purple 78A for sepal. Dried flower colour of different harvest stages was matching with purple colour (Purple 77A). Results of sensory evaluation on dried flower colour as influenced by different harvest stages are presented in table 13. Maximum sensory score of for colour retention of dried flowers of ¾ th harvest stage followed by sensory score of for colour retention of dried flowers of fully opened harvest stage of Dendrobium orchid var. Sonia-17. Minimum sensory score of 9.40 was obtained in half open stage flowers Dried flower texture Significant differences were observed for flower texture of different harvest stages of Dendrobium orchid var. Sonia-17. Maximum sensory score of was given to the dried flower texture of ¾ th opened harvest stage followed by sensory score of was given to the texture of fully opened harvest stage dried flowers. Minimum sensory score of was given to the texture of half opened harvest stage dried flowers.

74 Table 13. Effect of harvest stages on sensory score of colour, texture and shape of dried flowers of Dendrobium orchid var. Sonia-17 Harvest stages Colour Texture Shape Half opened ¾ th opened Fully opened Mean SEM± CD F-test * * * Very Good : Good : Average : Poor : 6-10 Very Poor : 0-5 Table 14. Effect of harvest stages on fresh and dried flower diameter of Dendrobium orchid var. Sonia-17 Harvest stages Fresh flower diameter (cm) Dried flower diameter (cm) Half opened ¾ th opened Fully opened Mean SEM ± CD F-test * *

75 4.2.8 Dried flower shape Sensory score of dried flower qualities of different harvest stages were recorded and given in table 13. Shape of dried flowers of different harvest stages varied significantly. Maximum sensory score of was given to the shape of ¾ th opened harvest stage dried flowers followed by sensory score of was given to the shape of fully opened harvest stage dried flowers. Minimum sensory score of was given to the shape of half opened harvest stage dried flowers Fresh and dried flower diameter Data on flower diameter was recorded and was statistically analyzed and presented in tables Significant differences were observed among the fresh flower diameter of different harvest stages of Dendrobium orchid var. Sonia-17. Maximum diameter of 6.73 cm was recorded in fresh flowers of fully opened harvest stage followed by 5.60 cm of diameter of ¾ th opened harvest stage flowers whereas minimum diameter of 2.75 cm was observed in fresh flowers of half opened harvest stage. Dried flower diameter of Dendrobium orchid var. Sonia-17 varied significantly among the harvest stages. Maximum diameter of 6.68 cm was recorded in fully opened harvest stage dried flowers followed by 5.46 cm diameter in ¾ th opened harvest stage dried flowers. Minimum flower diameter of 2.66 cm was recorded in half opened harvest stage dried flowers. Petal, sepal and labellum size of fresh flowers of Dendrobium orchid var. Sonia- 17 was found significant among the flowers of different harvest stages. Maximum petal size of 3.16 cm was recorded in fresh flowers of fully opened harvest stage whereas minimum petal size of 2.43 cm was recorded in half opened harvest stage flowers. Maximum sepal size of 2.58 cm was recorded in fresh flowers of fully opened harvest stage followed by sepal size 2.26 cm in fresh flowers of ¾ th opened harvest stage while

76 Table 15. Effect of harvest stages on petal, sepal and labellum size of fresh flowers of Dendrobium orchid var. Sonia-17 Harvest stages Petal (cm) Sepal (cm) Labellum (cm) Half opened ¾ th opened Fully opened Mean SEM ± CD F-test * * * Table 16. Effect of harvest stages on petal, sepal and labellum size of dried flowers of Dendrobium orchid var. Sonia-17 Harvest stages Petal diameter (cm) Sepal diameter (cm) Labellum diameter (cm) Half opened ¾ th opened Fully opened Mean SEM ± CD F-test * * *

77 minimum sepal size of 2.01 cm was recorded in half opened harvest stage flowers. Labellum size was maximum in fresh flowers of fully opened harvest stage (2.21 cm) followed by labellum size of 1.93 cm in ¾ th opened harvest stage flowers whereas minimum labellum size of 1.69 cm in fresh flowers of half opened harvest stage flowers. Dried flower size of petal, sepal and labellum varied significantly among the harvest stages. Maximum petal size of 2.98 cm was recorded with fully opened harvest stage dried flowers whereas minimum petal size of 2.18 cm was recorded with half harvest opened stage dried flowers. Sepal size of 2.41 cm was found maximum in fully opened harvest stage dried flowers followed sepal size of 2.19 cm with ¾ th opened harvest stage dried flowers whereas minimum sepal size of 1.88 cm was recorded with half opened harvest stage dried flowers. Labellum size was also found to be maximum in fully opened harvest stage dried flowers (2.04 cm) followed by labellum size of 1.81 cm in ¾ th opened harvest stage dried flowers. Minimum labellum size of 1.56 cm was recorded with half opened harvest stage dried flowers. 4.3 Experiment-3: Effect of embedding media, drying methods and positioning on dried flowers quality Observations on dry weight, drying rate, per cent moisture loss, flexibility, flower diameter and sensory score of dried flower qualities of Dendrobium var. Sonia-17 flowers are presented in tables Dry weight Data on dry weight of flowers of Dendrobium orchid var. Sonia-17 as influenced by embedding media, drying methods and positioning are presented in table 17. Individual effect of embedding media on dry weight of flower was significant. Maximum dry weight of flower was 0.29 g in sand embedded dried flowers followed by dried flower weight of 0.28 g in combination of silica gel and sand embedding whereas minimum dry weight of 0.26 g was obtained in silica gel alone embedded dried flowers. Drying methods had a significant effect on dried flower weight of Dendrobium orchid

78 Table 17. Effect of embedding media, drying methods and positioning on dry weight, per cent moisture loss, drying rate (g/h) and flexibility (º) of Dendrobium orchid var. Sonia-17 flowers Sl No Treatments Embedding media (E) Silica gel Sand Silica gel and sand SEM± CD at 5% Drying methods (D) Hot air oven Ambient SEM± CD at 5% Positioning (P) Face up Face down SEM± CD at 5% Interaction effect (E x D) Dry weight (g) NS Per cent moisture loss NS Drying rate (g/h) Flexibility (º) NS Silica gel x Hot air oven Silica gel x Ambient Sand x Hot air oven Sand x Ambient Silica gel and sand x Hot air oven Silica gel and sand x Ambient SEM± CD at 5% NS NS- Non significant Contd...

79 (Contd... table 17) Sl No. Treatments Interaction effect (E x P) Dry weight (g) Per cent moisture loss Drying rate (g/h) Flexibility (º) 1. Silica gel x Face up Silica gel x Face down Sand x Face up Sand x Face down Silica gel and sand x Face up Silica gel and sand x Face down SEM± CD at 5% Interaction effect (D x P) NS 0.21 NS Hot air oven x Face up Hot air oven x Face down Ambient x Face up Ambient x Face down SEM± CD at 5% NS- Non significant NS 0.17 NS Contd...

80 (Contd... table 17) Sl No. 1. Treatments Interaction effect of (E x D x P) Silica gel x Hot air oven x Face up Dry weight (g) 0.23 Per cent moisture loss Drying rate (g/h) 2.68 Flexibility (º) Silica gel x Hot air oven x Face down Silica gel x Ambient x Face up Silica gel x Ambient x Face down Sand x Hot air oven x Face up Sand x Hot air oven x Face down Sand x Ambient x Face up Sand x Ambient x Face up Silica gel and sand x Hot air oven x Face up Silica gel and sand x Hot air oven x Face down Silica gel and sand x Ambient x Face up Silica gel and sand x Ambient x Face down SEM± CD at 5% NS- Non- significant NS NS NS NS

81 var. Sonia- 17. Maximum dry weight of 0.29 g was obtained with ambient dried flowers followed by 0.26 g dry weight of dried flowers in hot air oven. Interaction effects of embedding media and drying methods were significant on dry weight of Dendrobium orchid Sonia-17 flowers. Maximum dry weight of 0.29 g was recorded in sand embedded ambient dried flowers. Least dry weight of 0.23 g was recorded in silica gel embedded hot air oven dried flowers. Interaction effect of embedding media and positioning on flower dry weight were found to be non - significant. Similarly, effect of drying methods and positioning on dried flower weight were found non - significant. Interaction effect of embedding media, drying methods and positioning on dry weight of flowers was also found non - significant Per cent moisture loss Data on per cent moisture loss as influenced by embedding media, drying methods and positioning were recorded and presented in table 17. Individual effect of embedding media, drying methods on per cent moisture loss were found significant whereas positioning of flowers had no effect on per cent moisture loss. Maximum moisture loss of per cent was recorded in silica gel embedded dried flowers followed by a moisture loss of per cent in combination of silica gel and sand embedded dried flowers. Minimum of per cent moisture loss was observed in sand embedded dried flowers. Maximum moisture loss of per cent was recorded in hot air oven dried flowers followed by per cent in ambient dried flowers.

82 Interaction effect of embedding media and drying methods, embedding media and positioning and interaction between drying methods and positioning on per cent moisture loss were found non- significant. Interaction effects of embedding media, drying methods and positioning on per cent moisture loss were found non-significant Drying rate Data on drying rate of Dendrobium orchid var. Sonia-17 as influenced by embedding media, drying methods and positioning are presented in table 17. Individual effect of embedding media, drying methods and positioning of flowers on drying rate of Dendrobium orchid flowers were found significant. Maximum drying rate of 1.00 g/ h was recorded in silica gel dried flowers followed by a drying rate of 0.85 g/ h in combination of silica gel and sand embedded dried flowers. Least drying rate of 0.52 g/ h was recorded in sand dried flowers. Among different drying methods tried, higher drying rate of 1.26 g/ h was recorded in hot air oven dried flowers followed by a drying rate 0.32 g/ h under ambient condition. Maximum drying rate of 0.92 g /h was recorded in flowers which were dried face up position followed by a drying rate of 0.66 g/h in flowers dried by face down position. Interaction effect of embedding media and drying methods on drying rate of Dendrobium orchid var. Sonia-17 flowers were found significant. Maximum drying rate of 1.67 g/ h was observed in silica gel embedded hot air oven dried flowers followed by a drying rate of 1.37 g/ h in silica gel and sand embedded hot air oven dried flowers. Minimum drying rate of 0.30 g/ h was observed in sand embedded ambient dried flowers. Interaction effect of embedding media and positioning had significant effect on drying rate of Dendrobium orchid var. Sonia-17. Silica gel embedded dried flowers at face up position had a maximum drying rate of 1.21 g/ h followed by a drying rate of

83 0.99 g/ h in combination of silica gel and sand embedded dried flowers at face up position. Minimum drying rate 0.48 g/ h in sand dried flowers at face down position. Interaction effect of drying methods and positioning had significant effect on drying rate of dried flowers of Dendrobium orchid var. Sonia-17. Maximum drying rate of 1.50 g/ h was recorded in hot air oven dried flowers at face up position followed by drying rate of 0.31 g/ h was observed in ambient dried flowers at face down position. Interaction effect of embedding media, drying methods and positioning on drying rate of Dendrobium orchid var. Sonia-17 were found non- significant Dried flower flexibility Data on flexibility of dried flowers of Dendrobium orchid var. Sonia-17 was recorded and is given in table 17. Individual effect of embedding media and positioning had significant effect on flower flexibility of dried Dendrobium orchid var. Sonia-17. Individual effect of drying methods on flexibility of dried flowers of Dendrobium orchid var. Sonia-17 was nonsignificant. Flexibility of 46.03º was found maximum in sand embedded dried flowers followed by flexibility of 44.84º in silica gel embedded dried flowers. Maximum flexibility of 44.67º was recorded in face up dried flowers followed by º of flexibility in face down positioned dried flowers. Interaction effect of embedding media and drying methods have significant effect on flexibility of dried flowers of Dendrobium orchid var. Sonia-17. Flexibility of 47.06º was found maximum in sand embedded dried flowers followed by 45.00º of flexibility in silica gel embedded ambient dried flowers which is on par with silica gel embedded hot air oven dried flowers (44.69º). Poor flexibility of 41.00º was observed in combination of silica gel and sand embedded dried flowers. Interaction effect of embedding media and positioning of flowers had significant effect on flexibility of dried flowers of Dendrobium orchid var. Sonia-17. Maximum

84 flexibility of 46.62º was observed with sand embedded dried flowers in face up position followed by flexibility of 45.75º with silica gel embedded dried flowers in face up position. Poor flexibility of 41.62º was recorded with the combination of silica gel and sand embedded dried flowers in face down position. Interaction effect of drying methods and positioning of flowers had significant effect on flexibility of dried flowers of Dendrobium orchid var. Sonia-17. Flexibility of º was found to be good in ambient dried flowers at face up position followed by 44.25º of flexibility of hot air oven dried flowers in face up position Dried flower colour Results of sensory evaluation of dried flower colour Dendrobium orchid var. Sonia-17 as influenced by embedding media, drying methods and positioning are presented in table 18. Individual effect of embedding media, drying methods and positioning on sensory score of dried flower colour found significant. Maximum sensory score of was received by silica gel embedded dried flowers followed by a sensory score of given to the sand embedded dried flowers (Plate 10). Minimum sensory score of was observed in combination of silica gel and sand embedded dried flower colour of Dendrobium orchid var. Sonia-17. Maximum sensory score of was given hot air oven dried flowers (Plate 11) followed by sensory score of given to the colour of ambient dried flowers. Maximum sensory score of was given to the colour of face up dried flowers followed by sensory score of given to the colour of face down positioned dried flowers. Interaction effect of embedding media and drying methods on sensory score of Dendrobium orchid var. Sonia-17 harvested at ¾ th opened harvest stage was found significant. Maximum sensory score of was given to the colour of silica gel embedded hot air oven dried flowers followed by sensory score of given to the

85 Table 18. Effect of embedding media, drying methods and positioning on sensory score of colour, texture and shape of dried flowers of Dendrobium orchid var. Sonia-17 Sl No. Treatments Colour Texture Shape Embedding media (E) Silica gel Sand Silica gel and sand SEM± CD at 5% Drying methods (D) Hot air oven Ambient SEM± CD at 5% Positioning (P) Face up Face down SEM± CD at 5% Interaction effect (E x D) Silica gel x Hot air oven Silica gel x Ambient Sand x Hot air oven Sand x Ambient Silica gel and sand x Hot air oven Silica gel and sand x Ambient SEM± CD at 5% Contd...

86 Contd... table 18) Sl No. 1. Treatments Colour Texture Shape Interaction effect (E x P) Silica gel x Face up Silica gel x Face down Sand x Face up Sand x Face down Silica gel and sand x Face up Silica gel and sand x Face down SEM± CD at 5% NS 1.08 NS Interaction effect (D x P) 1. Hot air oven x Face up Hot air oven x Face down Ambient x Face up Ambient x Face down SEM± CD at 5% NS 1.08 NS NS- Non significant Contd...

87 (Contd... table 18) Sl No. Treatments Colour Texture Shape Interaction effect of (E x D x P) 1. Silica gel x Hot air oven x Face up Silica gel x Hot air oven x Face down Silica gel x Ambient x Face up Silica gel x Ambient x Face down Sand x Hot air oven x Face up Sand x Hot air oven x Face down Sand x Ambient x Face up Sand x Ambient x Face up Silica gel and sand x Hot air oven x Face up Silica gel and sand x Hot air oven x Face down Silica gel and sand x Ambient x Face up Silica gel and sand x Ambient x Face down SEM± CD at 5% NS NS NS NS- Non significant

88 a b c Plate 10. Dried flowers of Dendrobium orchid var. Sonia-17 a. Silica gel, b. Sand and c. Silica gel and sand(1:1) embedded in hot air oven a b Plate 11. Silica gel embedded (a) Hot air oven and (b) Ambient dried flowers dried flowers

89 colour of sand embedded hot air oven dried flowers. Least sensory score of 9.12 was given to the colour of combination of silica gel and sand embedded ambient dried flowers. Interaction effect of embedding media and positioning on dried flower colour of Dendrobium orchid var. Sonia-17 was non- significant. Similarly interaction effect of drying methods and positioning was also found non- significant. Interaction effect of embedding media, drying methods and positioning on dried flower colour of Dendrobium orchid var. Sonia-17 was also found non- significant Dried flower texture Data on sensory evaluation on dried flower texture of Dendrobium orchid var. Sonia-17 harvested at ¾ th opened stage as influenced by embedding media, drying methods and positioning are presented in table 18. Individual effect of embedding media, drying methods and positioning on sensory score of dried flower texture of Dendrobium orchid var. Sonia-17 found significant. Maximum sensory score of was obtained by texture of sand embedded dried flowers followed by sensory score of obtained by texture of silica gel embedded dried flowers. Minimum sensory score of was given to the dried flower texture obtained in combination of sand and silica gel drying. Sensory score of was given to hot air oven dried flower texture followed by sensory score of was given to the ambient dried flower texture. Maximum sensory score of was given to the texture of dried flowers in face up position followed by sensory score of for face down dried flowers. Interaction effect of embedding media and drying methods had significant effect on dried flower texture of Dendrobium orchid var. Sonia-17 flowers harvested at ¾ th opened stage. Sand embedded hot air oven dried flowers obtained maximum sensory score of for texture followed by a sensory score of to the texture of silica gel

90 embedded hot air oven dried flowers. Minimum sensory score of for the texture of combination of silica gel and sand embedded ambient dried flowers. Interaction effect of embedding media and positioning had significant effect on texture of dried flowers of Dendrobium orchid var. Sonia-17 harvested at ¾ th opened stage. Sensory score of was recorded for dried flower texture in sand embedded face up position followed by sensory score of for texture of silica gel embedded dried flowers at face up position. Least sensory score of was given to the texture of dried flowers in combination of silica gel and and sand embedded at face down position. Interaction effect of drying methods and positioning had significant effect on texture of dried flowers of Dendrobium orchid var. Sonia-17. Maximum sensory score of was recorded for the texture hot air oven dried flowers at face up position followed by sensory score of for texture of hot air oven dried flowers at face down position. Least sensory score of was given to texture of ambient dried flowers at face down position Dried flower shape Score given by the panel of members during the sensory evaluation of Dendrobium orchid var. Sonia-17 for dried flower shape is given in table 18. Individual effect of embedding media, drying methods and positioning had a significant effect on sensory score of dried flower shape of Dendrobium var. Sonia-17 harvested at ¾ th opened stage. Maximum sensory score of was obtained in silica gel embedded dried flowers followed by sensory score of was given to the shape of dried flower obtained by sand embedded drying. Minimum sensory score of 9.00 was given to the shape of dried flowers obtained in combination of silica gel and sand embedded drying. Sensory score of was given to the shape of hot air oven dried flowers followed by sensory score of given to the shape of ambient dried flowers.

91 Interaction effect of embedding media and drying methods had a significant effect on sensory score for dried flower shape of Dendrobium orchid var. Sonia-17. Maximum sensory score of was obtained by silica gel embedded hot air oven dried flowers. Least sensory score of 8.50 was given to the shape of dried flowers obtained in combination of silica gel and sand embedded under ambient condition. Interaction effect of embedding media and positioning had significant effect on dried flower shape of Dendrobium orchid var. Sonia-17 at ¾ th opened stage. Maximum sensory score of was given to the shape of dried flowers obtained by silica gel embedded drying in face up position. Minimum score of 8.75 was given to the shape of dried flowers obtained by combination of silica gel and sand embedded drying in face down position. Interaction effect of drying methods and positioning on dried flower shape of Dendrobium orchid var. Sonia-17 was found non-significant. Similarly interaction effect of embedding media, drying methods and positioning on dried flower shape of Dendrobium orchid var. Sonia-17 was also found non-significant Flower diameter Fresh and dried flower diameter of Dendrobium orchid var. Sonia-17 did not differed significantly. Hence, data on dried flower diameter has not been presented here. 4.4 Experiment -4: Evaluation of shelf life of dried flowers Dendrobium orchid var. Sonia-17 Data of dried flower colour, texture and shape. Shelf life evaluation based on of Dendrobium var. Sonia-17 flowers harvested at ¾ th opened stage and embedded dried in silica gel hot air oven is given in tables 19 and Dried flower colour Data on sensory score of dried flower colour of Dendrobium orchid var. Sonia-17 is given in table 19. Individual effect of packaging and storage was significant on colour of dried flowers of Dendrobium orchid var. Sonia-17. Maximum sensory score of 17.87

92 Table 19. Effect of packaging and storage condition on sensory score of dried flowers of Dendrobium orchid var. Sonia-17 No. Treatments Before storage After storage Colour Texture Shape Colour Texture Shape Package (P) 1. Plastic container Polyethylene cover Control(open) SEM± CD at 5% Storage (Sc) Dark Light 0.18 NS NS NS SEM± CD at 5% Interaction effect (P x Sc) Plastic container x Dark 0.14 NS NS NS NS Plastic container x Light Polyethylene cover x Dark Polyethylene cover x Light Control (open) x Dark Control (open)x Light SEM± CD at 5 % 0.25 NS 0.29 NS 0.75 NS NS NS- Non significant Very Good : 21-25, Good : 16-20, Average : 11-15, Poor : 6-10 and Very Poor : 0-5

93 was given to the colour of dried flowers packed in an air tight plastic container. Minimum sensory score of was given to the colour of control dried flowers. Maximum sensory score of was given to the colour of dried flowers stored under dark condition followed by sensory score of by colour of dried stored under light in open. Interaction effect of packaging and storage had significant effect on colour retention of Dendrobium orchid var. Sonia-17 dried flowers. Maximum sensory score of was given to the colour of dried orchid flowers packed in an air tight plastic container stored under dark condition (Plate 12) followed by sensory score of given to the colour dried flowers packed in polyethylene covers and stored under dark condition. Least sensory score of was given to the colour of dried flowers stored under light in open without package Dried flower texture Data on dried flower texture of Dendrobium orchid var. Sonia-17 harvested at ¾ th opened stage flowers in silica gel embedded hot air oven is given in table 19. Packaging and storage had significant effect on dried flower texture of Dendrobium orchid var. Sonia-17. Maximum sensory score of was given to dried flowers packed in an air tight plastic container. Minimum sensory score of was obtained by texture of dried flowers held open. Sensory score of was given to the texture of dried flowers stored under dark condition followed by sensory score of for texture of dried flowers stored under light in open. Interaction effect of packaging and storage was also found significant on dried flower texture of Dendrobium orchid var. Sonia-17. Maximum sensory score of was given to the texture of dried flowers packed in an air tight plastic container stored under dark followed by sensory score of was given to the texture of dried flowers packed in polyethylene cover and package stored under dark. Minimum sensory score of was given to the texture of dried flowers stored open under light.

94 a b Plate 12. Dried flowers of Dendrobium orchid var. Sonia-17 stored under a. Dark and b. Light in an air tight plastic container

95 4.4.3 Dried flower shape Data on dried flower shape of Dendrobium orchid var. Sonia-17 harvested at ¾ th opened stage is presented in table 19. Packaging had significant effect on dried flower shape of Dendrobium orchid var. Sonia-17, whereas the effect of packaging and storage on dried flower shape was non- significant. Maximum score of was given to the dried flower shape of Dendrobium orchid var. Sonia-17 packed in an air tight plastic container followed by sensory score of for the shape of the dried flowers packed in polyethylene covers. Least sensory score of was given to the shape of dried flowers held open (control) Dried flower flexibility Data on flexibility of dried flowers as influenced by packaging and storage condition is given in table 20. Packaging had a significant effect on flexibility of dried flowers, whereas effect of storage on flexibility of dried flowers was found to be nonsignificant. Flexibility was good in dried flowers held without package (46.50º) followed by flexibility of 44.50º with dried flowers packed in an air tight plastic container. Interaction effect of packaging and storage on flexibility of dried flowers was found significant. Flowers without any package stored under dark condition had good flexibility of 47.00º. Poor flexibility of 42.00º was observed in polyethylene cover package at both dark and light condition Shelf life Shelf life of dried flowers of Dendrobium orchid var. Sonia-17 was evaluated based on qualities viz., shape, size, texture and colour of dried flowers and are presented in table 20. Shelf life of dried flowers of Dendrobium orchid var. Sonia-17 were found significant. Dried flowers packed in an air tight plastic container had shelf life of five months whereas dried flowers without any package had shelf life of two months.

96 Table 20. Effect of packaging and storage condition on flexibility and shelf life of dried flowers of Dendrobium orchid var. Sonia-17 Sl No. Treatments Flexibility(º) Shelf life (Months) 1. Package (P) Plastic container Polyethylene cover Control (open) SEM± CD at 5% Storage (Sc) Dark Light SEM± CD at 5% 0.19 NS Interaction effect (P x Sc) 1. Plastic container x Dark Plastic container x Light Polyethylene cover x Dark Polyethylene cover x Light Control (open) x Dark Control (open)x Light SEM± CD at 5 % NS- Non significant

97 Storage conditions had significant effect on shelf life of dried flowers of Dendrobium orchid var. Sonia-17. Dried flowers stored under dark condition had shelf life of four months, whereas flowers stored under light had shelf life of three months. Interaction effect of packaging and storage was found significant on shelf life of dried flowers. Dried flowers packed in an air tight plastic container and storage under dark condition extended the shelf life more than six months, whereas dried flowers stored without any package under light had shelf life of two months. 4.5 Experiment -5: Product diversification of Dendrobium orchid dried flowers of var. Sonia Sensory score Diversified products of dried flowers of Dendrobium orchid var. Sonia-17 were evaluated for their acceptability. The sensory scores obtained by the diversified orchid products are presented in table 21. Sensory evaluation revealed that maximum sensory score of was given to the floral arrangements in acrylic package followed by sensory score of was given to floral arrangement in bamboo basket. Minimum sensory score of was given to dried labellum greeting card (Plate 13).

98 Table 21. Sensory score of dried flower products of Dendrobium orchid var. Sonia-17 Sl. No. Products Sensory score 1 Floral arrangement in acrylic package Floral arrangement in bamboo basket Dried labellum greeting Mean SEM± Very Good : Good : Average : Poor : 6-10 Very Poor : 0-5

99 Floral arrangement in acrylic package Dried labellum greeting card Floral arrangement in bamboo basket Plate 13. Dried flower products of Dendrobium orchid var. Sonia-17

100

101 V DISCUSSION Dried flower is an important product of floriculture industry, which is gaining importance and popularity at a faster rate in the international trade. However, dried flowers are earning better foreign exchange than fresh cut flowers, but not much systematic research has been carried out in this line. The techniques followed in the dried flower industry are maintained as trade secrets. In the present investigation, attempts were made to standardize the dehydration through selection of suitable variety, optimum harvest stage, drying methods and desiccants for superior quality of dried flowers of Dendrobium orchids. Also an effort was made to standardize the method of packaging and storage techniques to extend the shelf life of dried flowers of Dendrobium orchid. The results obtained are discussed in this chapter. 5.1 Experiment - 1: Evaluation of Dendrobium orchid varieties for suitability to dried flowers In the present study, three Dendrobium orchid varieties viz., Sonia-17, Emma White and Caesar Red flowers were evaluated for dried flower quality by recording observations on fresh weight, dry weight, per cent moisture loss, drying rate, flower diameter, flower flexibility, colour, shape and texture. Results of these parameters are discussed below. Fresh weight of Dendrobium orchid flowers varied significantly among the varieties evaluated. Maximum fresh weight of 2.86 g was recorded in Dendrobium orchid var. Sonia-17 whereas minimum fresh weight of 1.45 g was recorded in var. Emma White (Fig 1). Dry weight of Dendrobium orchid flowers also varied significantly among the varieties evaluated. Varietal variation in fresh flower diameter was also observed. Therefore dry weight of flowers also varied among varieties. Maximum dry weight of 0.32 g was recorded in Dendrobium orchid var. Sonia- 17 (Fig. 2). Similarly Meeteren (1988) has stated that variation in dry weight of varieties is attributed to the differences in genetic characters of the varieties.

102 Fig 1. Fresh weight of flowers of Dendrobium orchid varieties Fig 2. Dry weight of flowers of Dendrobium orchid varieties

103 Per cent moisture loss of Dendrobium orchid flowers varied significantly. Among three varieties evaluated Dendrobium orchid var. Sonia- 17 had maximum per cent moisture loss of whereas flowers of var. Caesar Red had least per cent moisture loss of (Fig 3). Variation in per cent moisture loss is due to the inherent structural and physiological characters of varieties. Flowers of Dendrobium orchid var. Sonia- 17 exhibited a good amount of moisture with lot of reserves (dry matter) as compared to other varieties. Significant differences were observed among the drying rate of the flowers of the varieties evaluated. Drying rate was maximum with flowers of Dendrobium orchid var. Sonia- 17 (1.75 g/h) whereas flowers of var. Caesar Red had a least drying rate of 1.41 g/ h (Fig 4). This is due to the hydrosorbance nature of silica gel. Similarly, Roberts (1997) reported that silica gel, drying agent had the capacity to absorb large quantities of moisture (up to 40%) and could quickly dehydrate cut flowers like cosmos, aster, calendula and candy tuft. Flexibility of dried flowers differed significantly among the Dendrobium orchid varieties. Dendrobium orchid var. Sonia- 17 showed a very good flexibility of 42.00º of angle of breakage whereas the var. Emma White showed a least angle of breakage (22.0º).This may be due to least dry weight of flowers in var. Emma White which has resulted in poor flexibility. Significant differences were observed in fresh flower diameter of Dendrobium orchid varieties evaluated. Fresh flower diameter was maximum (6.85 cm) in var. Caesar Red. Minimum fresh flower diameter of 6.67 cm was recorded in var. Emma White (Table 6). Dried flower size of Dendrobium orchid varied significantly among the varieties. Maximum dried flower diameter of 6.76 cm was recorded in var. Caesar Red. Minimum flower diameter of 6.60 cm was recorded in var. Emma White. This is attributed to the inherent difference in the flower diameter of the varieties.

104 Fig 3. Per cent moisture loss of flowers of Dendrobium orchid varieties Fig 4. Drying rate (g/h) of flowers of Dendrobium orchid varieties

105 Petal, sepal and labellum size of fresh flowers was found significant. Maximum petal and sepal size of 3.16 cm and 2.59 cm, respectively was recorded with fresh flowers of Dendrobium orchid var. Sonia -17. Also maximum labellum size of 2.21 cm was recorded with var. Sonia-17 flowers. Dried flower size of petal, sepal and labellum was found significant among the varieties evaluated. Dendrobium orchid var. Sonia-17 had a maximum petal size of 2.98 cm. Maximum sepal and labellum size of 2.41 cm and 2.06 cm was observed in dried flowers of Dendrobium orchid var. Sonia-17. Minimum flower size of petal, sepal and labellum were observed in dried flowers of var. Caesar Red (Table 8). Larger size of flower is due to larger size of 2.65 cm of tepals (labellum, sepal and petal) in var. Sonia- 17. These may be due to the inherent characters of the varieties evaluated. Among the three varieties evaluated, Dendrobium orchid var. Sonia- 17 retained their original colour whereas flower colour of var. Emma White showed discolouration from its original colour. Significant differences were observed among the sensory score of dried flower texture was noticed. Dendrobium orchid var. Sonia-17 had better texture of dried flowers and obtained sensory score of This may be owing to its floral characters as compared to other varieties. Shape of dried flowers of Dendrobium orchids varied among the varieties evaluated. However, better sensory score of was given to the shape of dried flowers of Dendrobium orchid var. Sonia Experiment-2: Determination of optimum harvest stage for improved quality dried flowers Based on the results of the first experiment on varietal evaluation for suitability of dried flower, Dendrobium orchid var. Sonia-17 flowers were chosen under the experiment-2.

106 Further improvement of dried flower qualities through determination of optimum harvest stages of Dendrobium orchid var. Sonia-17 was carried out with half opened, ¾ th opened and fully opened harvest stage flowers and were evaluated for their dried flower colour, texture and shape. Observations on fresh weight, dry weight, per cent moisture loss, drying rate, flexibility and quality parameters such as colour, texture and shape of dried flowers are discussed below. Fresh weight of three harvest stages of Dendrobium orchid var. Sonia-17 flower varied significantly. Fully opened harvest stage flowers had maximum fresh weight of 2.86 g. Minimum fresh weight of 2.23 g was obtained in half opened harvest stage flowers (Fig 5). As the maturity increased the dry matter of the flowers also increased whereas moisture content decreased. Similar results were reported by Padmavathamma (1999) in statice flowers. Dry weight among flowers of different harvest stages varied significantly. Maximum dry weight of 0.31 g was recorded in fully opened harvest stage flowers. Minimum dry weight of 0.24 g was observed in half opened harvest stage flowers (Fig 6). This is mainly due to the fresh weight difference among the flowers of different harvest stages. Per cent moisture loss of these different harvest stages of Dendrobium orchid var. Sonia-17 differed significantly. Maximum moisture loss of per cent was obtained in ¾ th opened harvest stage flowers whereas minimum of per cent moisture loss was obtained in half opened harvest stage flowers (Fig 7). As ¾ th opened harvest stage flowers are in a physiological active state with high moisture content might have resulted in more moisture loss. Maximum drying rate of 1.95 g/ h was recorded in ¾ th opened harvest stage flowers whereas minimum drying rate of 1.50 g/ h was recorded in half opened harvest stage flowers. As ½ opened harvest stage flowers are smaller and had comparatively low moisture content, which resulted in low drying rate, compared to other harvest stages of flowers.

107 Fig 5. Effect of harvest stages on fresh weight of flowers of Dendrobium orchid var. Sonia-17 Fig 6. Effect of harvest stages on dry weight of flowers of Dendrobium orchid var. Sonia-17