DOWNLOAD PDF DESIGN OF COLD STORAGE FOR FRUITS AND VEGETABLES

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1 Chapter 1 : Cold Storage Fruit: Cold Room Panels for Fruit Cold Storage The cold storage of dried/dehydrated vegetables in order to maintain vitamin C, storage temperature can be varied with storage time and can be at 0Â Â C for a storage time of more than one year. One way to slow down this change and so increase the length of time fruits and vegetables can be stored, is by lowering the temperature to an appropriate level. It must be remembered that if the temperature is too low the produce will be damaged and also that as soon as the produce leaves the cold store, deterioration starts again and often at a faster rate. Harvesting It is essential that fruits and vegetables are not damaged during harvest and that they are kept clean. Damaged and bruised produce have much shorter storage lives and very poor appearance after storage. Dirty produce can introduce pests and moulds into the store. The produce should be harvested carefully using a sharp stainless steel knife. The fruits and vegetables should not be placed on the ground where they could pick up dirt. Either a clean harvesting basket or clean mats should be used. It is essential that the fruits and vegetables are harvested at the correct harvesting time. Handling It is important that the produce does not get dirty or damaged during handling. Careful handling should be the rule. The best option is for the produce to be prepared for storage in the field and placed carefully in the storage containers used in the cold store. This considerably reduces the amount of handling and will keep damage to a minimum. It is essential that the produce is handled and placed in the store as quickly as possible as delays between harvesting and cooling can substantially reduce storage life. Preparation If the produce is dirty it should be cleaned before storage. The water used has to be kept clean or fungus spores will be spread throughout the produce. Some fruit and vegetables need their outer leaves removed before storage. However, usually it is better to leave the leaves on during storage to reduce moisture loss, and then remove them before sale. Preliminary cooling Precooling Dipping the produce in cool water to remove field heat can reduce the energy requirements of the store. However, this can spread fungus spores throughout the produce. A suitable alternative is to pick the produce either early in the morning when it is cool or late in the evening and leave it overnight to cool down. Carrots for example blacken and become soft, and the cell structure of potatoes is destroyed. The storage temperature always has to be above this critical temperature. One has to be careful that even though the thermostat is set at a temperature above the critical temperature, the thermostatic oscillation in temperature does not result in storage temperature falling below the critical temperature. Table 1 gives the critical temperatures for various fruits and vegetables. Page 1

2 Chapter 2 : Cold storage of fruit and vegetables - Appropedia: The sustainability wiki DESIGN OF COLD STORAGE FOR FRUITS AND 1. Introduction Cold storage is the one widely practiced method for bulk handling of the perishables between production and marketing processing. One way to slow down this change and so increase the length of time fruits and vegetables can be stored, is by lowering the temperature to an appropriate level. It must be remembered that if the temperature is too low the produce will be damaged and also that as soon as the produce leaves the cold store, deterioration starts again and often at a faster rate. Harvesting[ edit ] It is essential that fruits and vegetables are not damaged during harvest and that they are kept clean. Damaged and bruised produce have much shorter storage lives and very poor appearance after storage. Dirty produce can introduce pests and moulds into the store. The produce should be harvested carefully using a sharp stainless steel knife. The fruits and vegetables should not be placed on the ground where they could pick up dirt. Either a clean harvesting basket or clean mats should be used. It is essential that the fruits and vegetables are harvested at the correct harvesting time. Handling[ edit ] It is important that the produce does not get dirty or damaged during handling. Careful handling should be the rule. The best option is for the produce to be prepared for storage in the field and placed carefully in the storage containers used in the cold store. This considerably reduces the amount of handling and will keep damage to a minimum. It is essential that the produce is handled and placed in the store as quickly as possible as delays between harvesting and cooling can substantially reduce storage life. Preparation[ edit ] If the produce is dirty it should be cleaned before storage. The water used has to be kept clean or fungus spores will be spread throughout the produce. Some fruit and vegetables need their outer leaves removed before storage. However, usually it is better to leave the leaves on during storage to reduce moisture loss, and then remove them before sale. Preliminary cooling Precooling [ edit ] Dipping the produce in cool water to remove field heat can reduce the energy requirements of the store. However, this can spread fungus spores throughout the produce. A suitable alternative is to pick the produce either early in the morning when it is cool or late in the evening and leave it overnight to cool down. Carrots for example blacken and become soft, and the cell structure of potatoes is destroyed. The storage temperature always has to be above this critical temperature. One has to be careful that even though the thermostat is set at a temperature above the critical temperature, the thermostatic oscillation in temperature does not result in storage temperature falling below the critical temperature. Table 1 gives the critical temperatures for various fruits and vegetables. Page 2

3 Chapter 3 : fruits and vegetables cold storage, vegetable cold room COLD STORAGE OF FRUITS AND []. Deterioration of fruits and vegetables during storage depends largely on temperature. One way to slow down this change and so increase the length of time fruits and vegetables can be stored, is by lowering the temperature to an appropriate level. Besides, quality of a sizable quantity of produce also deteriorates by the time it reaches the consumer. Most of the problems relating to the marketing of fruits and vegetables can be traced to their perishability. Perishability is responsible for high marketing costs, market gluts, price fluctuations and other similar problems. At low temperature, perishability is considerably reduced and the shelf life is increased and thus the importance of cold storage or refrigeration. The first cold store in India was reported to have been established in Calcutta in However significant progress in the expansion of the cold storage industry in the country has been made only after independence. With a view to ensuring the observance of proper conditions in the cold stores and to providing for development of the industry in a scientific manner, the govt of India and the ministry of agriculture promulgated an order known as "Cold Storage Order, " under Section 3 of the Essential Commodities Act, A cold storage facility accessible to them will go a long way in removing the risk of distress sale to ensure better returns. Status of Cold storage and its potential in India The estimated annual production of fruits and vegetables in the country is about million tonnes. Due to diverse agro climatic conditions and better availability of package of practices, the production is gradually rising. Although, there is a vast scope for increasing the production, the lack of cold storage and cold chain facilities are becoming major bottlenecks in tapping the potential. The cold storage facilities now available are mostly for a single commodity like potato, orange, apple, grapes, pomegranates, flowers, etc. Storage of foods and Storage Conditions Foods and many other commodities can be preserved by storage at low temperature, which retards the activities of micro organisms. Micro organisms are the spoilage agents and consist of bacteria, yeasts and molds. Low temperature does not destroy those spoilage agents as does high temperature, but greatly reduces their activities, providing a practical way of preserving perishable foods in their natural state which otherwise is not possible through heating. The low temperature necessary for preservation depends on the storage time required often referred to as short or long term shortage and the type of product. In general, there are three groups of products: Foods that are alive at the time of storage, distribution and sale e. Living foods such as fruits and vegetables have some natural protection against the activities of micro organism. The best method of preserving these items is to keep the product alive and at the same time retard the natural enzyme activity which will retard the rate of ripening or maturity. Preservation of non-living foods is more difficult since they are susceptible to spoilage. The problem is to preserve dead tissues from decay and putrefaction. Long term storage of meat and fish product can only be achieved by freezing and then by storing it at temperature below oc. Only certain fruits and vegetables can benefit from freezing. However, for fruits and vegetables one should be very careful about the recommended storage temperature and humidity a deviation from which will have adverse effect on the stored product leading to even loss of the entire commodity. Products such as apples, tomatoes, oranges, etc. Some product can also be benefited by storing under controlled atmosphere and modified atmosphere conditions. Dairy products are produced from animal fats and therefore non living foodstuffs. They suffer from the oxidation and breakdown of their fats, causing rancidity. Packaging to exclude air and hence Oxygen can extend storage life of such foodstuffs. Technology A cold storage unit incorporates a refrigeration system to maintain the desired room environment for the commodities to be stored. A refrigeration system works on two principles: Vapour absorption system VAS, and Vapour compression system VCS VAS, although comparatively costlier, is quite economical in operation and adequately compensates the higher initial investment. Wherever possible such a system should be selected to conserve on energy and operational cost. However, it has its own limitations when temperature requirement is below C and many of the fruits and vegetables except seeds, mango, etc. There are three types of VCS systems Page 3

4 available depending upon the cooling arrangements in the storage rooms i. Diffuser type is comparatively costlier and is selected only when the storage room heights are low. The operational cost of such units is also higher. Bunker type is the cheapest and is preferred when storage room heights normally exceeds Its operational cost is also low. Such system is used for units with room heights of 5. In a refrigeration system, refrigerants are used to pick up heat by evaporation at a lower temperature and pressure from the storage space and give up the heat by condensation at a higher temperature and pressure in a condenser. Freon used to be a common refrigerant but as it causes environmental degradation, its use is going to be banned by the year Therefore, Ammonia is being increasingly used and preferred for horticultural and plantation produce in cold storage units. Heat load factors normally considered in a cold storage design are: Wall, floor and ceiling heat gains due to conduction Wall and ceiling heat gains from solar radiation Load due to ingression of air by frequent door openings and during fresh air charge. Product load from incoming goods Heat of respiration from stored product Heat from workers working in the room Cooler fan load. Page 4

5 Chapter 4 : How to Preserve Fruit and Vegetable by Cold Storage - Howtopedia - english In addition to the control of temperature and moisture in the cold room, we need to consider the respiration of plants in the cold room at the same time, but also regulate and control O2, CO, N2, and ethylene, inhibits respiration and metabolism of fruits, vegetables and other plants in a dormant state, in order to achieve the purpose of long. One way to slow down this change and so increase the length of time fruits and vegetables can be stored, is by lowering the temperature to an appropriate level. It must be remembered that if the temperature is too low the produce will be damaged and also that as soon as the produce leaves the cold store, deterioration starts again and often at a faster rate. Harvesting[ edit ] It is essential that fruits and vegetables are not damaged during harvest and that they are kept clean. Damaged and bruised produce have much shorter storage lives and very poor appearance after storage. Dirty produce can introduce pests and moulds into the store. The produce should be harvested carefully using a sharp stainless steel knife. The fruits and vegetables should not be placed on the ground where they could pick up dirt. Either a clean harvesting basket or clean mats should be used. It is essential that the fruits and vegetables are harvested at the correct harvesting time. Handling[ edit ] It is important that the produce does not get dirty or damaged during handling. Careful handling should be the rule. The best option is for the produce to be prepared for storage in the field and placed carefully in the storage containers used in the cold store. This considerably reduces the amount of handling and will keep damage to a minimum. It is essential that the produce is handled and placed in the store as quickly as possible as delays between harvesting and cooling can substantially reduce storage life. Preparation[ edit ] If the produce is dirty it should be cleaned before storage. The water used has to be kept clean or fungus spores will be spread throughout the produce. Some fruit and vegetables need their outer leaves removed before storage. However, usually it is better to leave the leaves on during storage to reduce moisture loss, and then remove them before sale. Preliminary cooling Precooling [ edit ] Dipping the produce in cool water to remove field heat can reduce the energy requirements of the store. However, this can spread fungus spores throughout the produce. A suitable alternative is to pick the produce either early in the morning when it is cool or late in the evening and leave it overnight to cool down. Carrots for example blacken and become soft, and the cell structure of potatoes is destroyed. The storage temperature always has to be above this critical temperature. One has to be careful that even though the thermostat is set at a temperature above the critical temperature, the thermostatic oscillation in temperature does not result in storage temperature falling below the critical temperature. Table 1 gives the critical temperatures for various fruits and vegetables. Storage conditions It can be seen from the table that there are basically three groups of fruit and vegetables: It is often more convenient to concentrate on one of these groups. Relative humidity[ edit ] For most produce, a high but not saturated, relative humidity is required, eg. Table 1 shows specific relative humidities for fruits and vegetables. There is always some moisture loss during cold storage but excessive moisture loss is a problem. This can be done by: Packing system[ edit ] A packing system is required so that the produce can be loaded and unloaded easily and safely. This can be a system using crates that can be stacked or a more complicated system using racks and trays. It is important that the crates are small enough to be moved easily when full of vegetables; are able to be easily and safely stacked and are strong enough to hold the weight of the other crates. It is essential that the airflow is not restricted, therefore a two foot gap should be left between the walls and the crates and three foot gap left between the crates, the ceiling and refrigeration units. Figure 1 shows the design of a crate that is suitable for cold stores. For small-scale cold storage systems, stackable crates are the most appropriate packing system. The layout plan for the crates needs to be simple and clear so that produce can be removed easily and quickly. Length of storage[ edit ] Table 1 gives the maximum storage times recommended by various organisations. These recommendations are based on figures from Europe and America and are often for too long for small-scale stores in tropical countries for the following reasons: It is often difficult to prevent delays between harvest and storage. The produce is often bruised during harvest and loading of the store. Transport can be Page 5

6 bumpy and result in damage. The temperature of the retail outlets is far higher than for the retail outlets in Europe and America. Incompatibility[ edit ] If different produce is being stored in the same room there is a risk of transfer of odours or ethylene. Table 2 shows the more important incompatibilities. Transport[ edit ] Care needs to be taken during the unloading of the cold store and during transport. If the produce can be transported in the same crates they were stored in, handling and concomitant damage will be reduced. Chapter 5 : Optimal Storage Temperature of Fruits and Vegetables Washington Cold Storage cold storage of fruits and vegetables Deterioration of fruits and vegetables during storage depends largely on temperature. One way to slow down this change and so increase the length of time fruits and vegetables can be stored, is by lowering the temperature to an appropriate level. Chapter 6 : Small-scale Cold Storage For Fruit and Vegetables in India - blog.quintoapp.com Engineering for Storage of Fruits and Vegetables is a comprehensive reference that provides an understanding of the basic principles of cold storage load estimation, refrigeration capacity calculations for various types of cold storages, and other topics of evaporative cooling, thus demonstrating the important principles for designing low cost precooling chambers. Chapter 7 : Agricultural Marketing :: COLD STORAGE Placing fruits and vegetables in storages, either in pits or in basement rooms, before cold weather starts in the fall is a frequent cause of early spoilage. Chapter 8 : Fruits And Vegetable Cold Storage - Manufacturer from Chennai Cold Storage of Fruits and Vegetables Deterioration of fruits and vegetables during storage depends largely on temperature. One way to slow down this change and so increase the length of time fruits and vegetables can be stored, is by lowering the temperature to an appropriate level. Page 6