What Lies Beneath: The Science Behind Contamination

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1 What Lies Beneath: The Science Behind Contamination

The Partnership for Food Safety Education delivers trusted, science based behavioral health messaging and a network of resources that support consumers in their efforts to reduce risk of foodborne

2 The Partnership for Food Safety Education delivers trusted, science based behavioral health messaging and a network of resources that support consumers in their efforts to reduce risk of foodborne illness. Support for the Partnership for Food Safety Education is provided by PFSE Contributing Partners, including: Cargill FMI Foundation Grocery Manufacturers Association NSF International Produce Marketing Association

CE certificates from the CDR and NEHA at teamfoodsafety.org > Resources > Presentations Email ashley@fightbac.org with questions! If you have a question, please type it into the chat box.

3 CE certificates from the CDR and NEHA at teamfoodsafety.org > Resources > Presentations with questions! If you have a question, please type it into the chat box. Please take the post-survey! It will help the Partnership to serve you better. Thank you, BAC! Fighters, for your work to prevent foodborne illness across the United States!

5 Fightbac.org > For Kids Fightbac.org > Campaigns > Produce Handling Fightbac.org > Campaigns > Mythbusters

7 Your intuition says giving bagged greens labeled ready-to-eat, washed, or triple washed an extra rinse couldn t possibly hurt. However, rinsing of ready-toeat greens will not enhance safety, but could increase the potential for crosscontamination. Pathogens that may be on your hands or on kitchen surfaces could find their way onto your greens in the process of handling them. Your ready-toeat greens have been prepared with your safety and convenience in mind - enjoy!

Some bacteria can survive and even grow in cool, moist environments like the refrigerator. In fact, Listeria monocytogenes grows at temperatures as low as 35.6 F!

10 Some bacteria can survive and even grow in cool, moist environments like the refrigerator. In fact, Listeria monocytogenes grows at temperatures as low as 35.6 F! A recent study from NSF International revealed that the refrigerator produce compartment was one of the germiest places in the kitchen, containing Salmonella and Listeria. In your refrigerator, keep fresh fruits and vegetables separate from raw meat, poultry, seafood, and eggs. Clean your refrigerator regularly with hot water and soap and clean up food and beverage spills immediately to reduce the risk of cross-contamination in your refrigerator. Don t forget to clean refrigerator walls and undersides of shelves!

12 Using a clean cloth or paper towel to blot dry fresh fruits and vegetables after rinsing is more important than you might realize! Research has found this drying step further reduces the level of harmful bacteria on the surface of fresh produce. Take a two-step approach to cleaning your produce: 1) just before use, rinse under running water only the fruits and vegetables you plan to eat, including those with skins or rinds that are not eaten. 2) dry fruits and vegetables with a clean cloth or paper towel.

The rind also touches the edible portion when cut fruit is arranged or stacked for serving and garnish.

14 Sure you re not eating the rind of the melon, but there are many ways for pathogens on the outside of the melon to contaminate the edible portion. A knife or peeler passing through the rind can carry pathogens from the outside into the flesh of the melon. The rind also touches the edible portion when cut fruit is arranged or stacked for serving and garnish. Play it safe and rinse your melon under running tap water while rubbing with your hands or scrubbing with a clean brush. Dry the melon with a clean cloth or paper towel. Once you ve used a towel to wipe hands or surfaces, it can look clean and still contain harmful bacteria.

Webinar Objectives: Surface contamination: survival times and pathogen transfer to food Produce contamination: causes and pathogen transfer to other foods and surfaces The

15 Webinar Objectives: Surface contamination: survival times and pathogen transfer to food Produce contamination: causes and pathogen transfer to other foods and surfaces The methodology, findings, and implications of a recent observational sanitation study Resources available for National Food Safety Education Month and beyond

16 Today s speakers: Bob Whitaker, Ph.D. Chief Science & Technology Officer Produce Marketing Association Robert Donofrio, Ph.D. Director, Applied Research Center NSF International

17 Dr. Bob Whitaker, Chief Science & Technology Officer Produce Marketing Association

18 Rinsing RTE greens does not enhance food safety Commercial systems washing to remove dust, other physical contaminates: no kill step! 1-2 log reduction in surface microbes Sanitizer to keep water clean In home - opportunity for cross contamination (contact surfaces) Prevalence, concentration low Not just on surface? Biofilms? More harm than good Parsley/cilantro Tolerance to oxidizing agents

19 Drying not often thought of Only 47% hand rub leaves RAC lettuce No soak and shake! Physical agitation help remove bacteria Clean paper towel; not cloth (Danyluk et al) Concept in commercial washing (Schneider et al) Drying removes moisture needed for growth Jensen Farms?

20 Hard, exterior you don t eat More likely to wash strawberries or tomatoes Are any surfaces really smooth? Knife pass through outside to inside can drag bacteria to inside Remember: prevalence and concentration! Inoculated cantaloupes: Scrubbing decrease Salmonella by 1 log Sanitizer to prevent transference Need to wash your tools! (Schneider et al)

21 Remove stems, outer leaves, dirt, etc.: Bacteria can hide there Dirt shields bacteria from water, sanitizers (McLandsborough - buckets, Danyluk cartons) Inspect fruits and vegetables: Damaged tissue a point of entry Source of nutrition Keep cut fruits and vegetables cold (40 F) Use within 2 hours

22 Robert Donofrio, Ph.D., Director, Applied Research Center NSF International

23 Part 1: NSF International Household Germ Study

NSF International NSF International has a long history in working to help ensure safe design and cleaning of equipment or appliances used in food preparation.

24 NSF International NSF International has a long history in working to help ensure safe design and cleaning of equipment or appliances used in food preparation. NSF s Commercial Foodservice Equipment Program began in the 1940s, focusing on restaurant equipment. NSF s Home Product Certification Program began in 2012, addressing kitchen appliances and tools used in the home. In addition to evaluating materials and design, the program evaluates manufacturers cleaning instructions to help prevent equipment from harboring pathogens that can cause foodborne illness.

25 NSF s Applied Research Center Provides custom research and development (R&D) services to advance public health in water safety, food safety, as well as healthcare and consumer products. Works with academia, industry and regulatory bodies for R&D projects focused on furthering public health in water safety, food safety, pharma, sustainability and consumer goods.

26 NSF International Household Germ Study Studies have shown that more than 20 percent of foodborne illness outbreaks result from food that was consumed in the home.* NSF International food safety experts point to a number of contributing factors, including improper food storage, handling and preparation. *Centers for Disease, Control and Prevention: Tracking and Reporting Food Disease Outbreaks,

27 NSF International Household Germ Study (cont.) In NSF s 2011 germ study, NSF scientists found more germs in the kitchen than in the bathroom. NSF s focus in the 2013 germ study was specific items in the kitchen (e.g. refrigerator, spatula, can opener, etc.). See Figures on next slide.

28 HPC Count on Household Objects Source: Donofrio et al. Journal of Env. Health Sept. 2012

29 Percent breakdown of yeast/mold, coliform, Staph, E. coli Source: Donofrio et al. Journal of Env. Health Sept. 2012

30 Methodology Germ Study was conducted by NSF International microbiologists July to Oct. 12, results published in Mar. 13. Swab kits, which included a swab for each of the 14 kitchen items to be analyzed, were provided to 20 volunteer families throughout greater Detroit. Scientific testing swab was saturated with a sterile medium with a neutralizer that helps to pick up germs from surfaces and neutralizes the affect of residual cleaners.

Methodology (cont.) Volunteers were instructed to wear gloves and rub the wet swab tip in a turning motion across a designated surface area of each of the 14 items.

refrigerator insulating seal, 10) refrigerator meat compartment, 11) refrigerator vegetable compartment, 12) refrigerator water dispenser, 13) rubber spatula, 14) strainer Volunteers then placed the

31 Methodology (cont.) Volunteers were instructed to wear gloves and rub the wet swab tip in a turning motion across a designated surface area of each of the 14 items. 1) blender gasket, 2) can opener, 3) flatware storage tray, 4) food storage container with rubber seal, 5) knife block, 6) microwave keypad, 7) pizza cutter, 8) refrigerator ice dispenser, 9) refrigerator insulating seal, 10) refrigerator meat compartment, 11) refrigerator vegetable compartment, 12) refrigerator water dispenser, 13) rubber spatula, 14) strainer Volunteers then placed the swab with the sample back into the swab container without touching the tip to anything else to ensure an accurate sample. Samples were analyzed by NSF microbiologists for the presence of targeted microorganisms such as E. coli, yeast and mold, Salmonella and Listeria.

Salmonella, E. coli, yeast and mold Blender gasket: Salmonella, E. coli, yeast and mold Can opener: Salmonella, E.

32 Findings NSF scientists determined that the six germiest items contained the following microorganisms that can cause sickness: Refrigerator vegetable compartment: Salmonella, Listeria, yeast and mold Refrigerator meat compartment: Salmonella, E. coli, yeast and mold Blender gasket: Salmonella, E. coli, yeast and mold Can opener: Salmonella, E. coli, yeast and mold Rubber spatula: E. coli, yeast and mold Food storage container with rubber seal: Salmonella, yeast and mold

33 Findings (Cont.)

34 Findings (Cont.) These germs were found on everyday kitchen appliances and tools that come in direct contact with food, especially raw produce, meat, poultry, seafood and ready-to-eat food. Volunteers correctly identified items that they thought would harbor the most germs, but they are not always cleaning them thoroughly to prevent illness.

35 Examination of Perception vs. Reality Before testing all these kitchen items, volunteers were asked to rate the items they thought would have the most germs. Asked what they perceived to be the germiest items in the kitchen versus the actual germiest items ranked from highest to lowest in germ count

36 Perception vs. Reality Volunteers thought: Actual: 1. Microwave keypad 1. Refrigerator water dispenser 2. Can opener 2. Rubber spatula 3. Refrigerator meat compartment 3. Blender 4. Refr. vegetable compartment 4. Refr. vegetable compartment 5. Flatware storage tray 5. Refrigerator ice dispenser 6. Knife block 6. Refr. meat compartment 7. Pizza cutter 7. Knife block 8. Rubber spatula 8. Food container rubber seal 9. Refrigerator insulating seal 9. Can opener 10. Ice dispenser 10. Refrigerator insulating seal

37 What volunteers thought was dirty but didn t clean properly Volunteers thought that the vegetable and meat compartments would rank among the dirtiest items in the kitchen and they were right. What many volunteers may not have realized is that the types of germs found in these areas were harmful (such as E. coli and Salmonella) and come into direct contact with food, especially raw produce. What we learned is that 1) it isn t enough to wash your produce, you must also wash the areas where the produce is stored and 2) storing clean and unwashed produce together can be problematic.

The refrigerator water dispenser didn t make their list at all, but both the water and ice dispensers proved to be

38 What volunteers thought was clean but wasn t Many volunteers didn t consider their blender a germy item, but in reality, it was the third germiest item in the kitchen. The refrigerator water dispenser didn t make their list at all, but both the water and ice dispensers proved to be areas of concern for yeast and mold, a problem for those with allergies. The food storage container never made the list, but later the data revealed it was one of the germiest items in the kitchen.

39 Lessons Learned Follow manufacturers directions when it comes to cleaning and sanitizing kitchen tools and appliances. Blenders need to be disassembled, and the gasket pulled apart from the base, to be cleaned. Refrigerator vegetable and meat compartments need to be cleaned and sanitized regularly. Like all kitchen tools, can openers need washing and sanitizing after each use and rubber spatulas that are detachable should be pulled off the handle to be cleaned. Rubber seals in food storage containers should be thoroughly cleaned. Detailed cleaning instructions for kitchen items included in the study are available on NSF International s website.

40 At-Risk Populations These germ study findings are most concerning for households with at-risk populations such as children, pregnant women, the elderly or those with a compromised immune system (from illness).

41 Part 2: Surface contamination

42 Pathogen Survival in the Refrigerator Refrigerator vegetable and meat compartments need to be cleaned and sanitized regularly. Storing food in contaminated storage containers or using water, ice or tools with high counts of yeast and mold may lead to food spoilage at a faster rate. For those with allergies to yeast and mold, these actions may lead to an allergenic response.

43 Pathogen Survival on Surfaces Some viruses and bacteria can live/survive from 20 minutes up to days on surfaces like doorknobs and tables. Follow manufacturer s directions when cleaning and sanitizing kitchen tools and appliances. Remember to disassemble before cleaning. Proper hand washing is key to help prevent the spread of germs: Thoroughly scrub hands w/ warm water with soap for 20 seconds before rinsing and drying with a clean towel.

44 Bacterium Discovered NSF discovered new bacterium - Klebsiella michiganensis on a bathroom toothbrush holder in 2011 household germ study. Same family as E. coli and Klebsiella pneumonia K. michiganensis has a capsule structure with a slimy surface that helps it attach to mucus membranes and evade immune system responses, which may lead to infection because the bacterium is difficult to break down. Published finding in Curr. Microbiol. in January 2013.

45 Klebsiella michiganensis Finding this bacterium in a toothbrush holder is particularly concerning due to the possibility of fecal matter contamination on products used for oral care. Sticky bacteria like K. michiganensis can attract other bacteria to join together in biofilm communities which are a common cause of persistent infections. These biofilms can form on surfaces such as human and animal tissues, metal and plastic and are more resistant to disinfection and removal than single bacteria.

Biofilms Figure 1. Pseudomonas aeruginosa biofilm life-cycle. Figure 2.

Rickard: E-mail The Corresponding Author, 1, Peter Gilbert1, Nicola J. High, 2, Paul E.

Bacterial coaggregation: an integral process in the development of multi-species biofilms, Trends

46 Biofilms Figure 1. Pseudomonas aeruginosa biofilm life-cycle. Figure 2. Coaggregation Image from Alexander H. Rickard: The Corresponding Author, 1, Peter Gilbert1, Nicola J. High, 2, Paul E. Kolenbrander, 3, and Pauline S. Handley, Bacterial coaggregation: an integral process in the development of multi-species biofilms, Trends in Microbiology Volume 11, Issue 2, February 2003, Pages Figure 3. Live/Dead staining in x-y and x-z aspect of a biofilm microcolony.

47 Biofilms (continued) Resistance to Antimicrobics Biofilms may be 1000 times more resistant to antibiotics (cleaners, disinfectants, sanitizers) compared to planktonic cells. May be due to degradation of the agent or exposure/penetration issues Physical treatment, in combination with antimicrobial treatment, is recommended

48 Key Takeaways Warm and moist environments tend to be breeding grounds for microorganisms Sponges and coffee reservoirs, which may not be cleaned as frequently as they should be, were in the top 10 germiest places in the home. Smooth, cold surfaces tend to harbor fewer germs. Be mindful of biofilms

49 Q&A Type your question in your dashboard!

org 202-220-0705 @Fight_BAC teamfoodsafety.

50 Stay In Touch! Please take the short survey immediately following this webinar so we can better serve you! /FightBAC BAC Fighter Friend teamfoodsafety.or g/field-reports-blog Upcoming Events: Next Webinar and Knowledge Exchange coming this spring! The Partnership for Food Safety Education

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52 Thank you for joining, and have a great National Food Safety Education Month!

Wash hands and surfaces often.

Wash hands and surfaces often. Fight BAC! Did You Know? It is important to consistently wash hands and kitchen surfaces before and after preparing food. 67 percent of Americans report they always wash cutting boards, utensils, and countertops