Presentation is loading. Please wait.

Presentation is loading. Please wait.

Chapter 13 Safety of Food and Water. Foodborne Illness Greatest risk from viral and bacterial contamination: Greatest risk from viral and bacterial contamination:

Similar presentations


Presentation on theme: "Chapter 13 Safety of Food and Water. Foodborne Illness Greatest risk from viral and bacterial contamination: Greatest risk from viral and bacterial contamination:"— Presentation transcript:

1 Chapter 13 Safety of Food and Water

2 Foodborne Illness Greatest risk from viral and bacterial contamination: Greatest risk from viral and bacterial contamination: –e.g. E. coli: O157:H7 (199 peo. 26 states fresh spinach (102 hospitalized, 31 kidney failure) Major cause of diarrhea Major cause of diarrhea Usually results from unsafe food handling in the HOME Usually results from unsafe food handling in the HOME Shiga Toxin E. coli: O157:H7

3 Most Susceptible to Foodborne Illness Infants and children Infants and children Older adults Older adults Those with liver disease, diabetes, HIV/AIDS, cancer Those with liver disease, diabetes, HIV/AIDS, cancer Pregnant women Pregnant women People taking immunosuppressant agents People taking immunosuppressant agents

4 Foodborne Illness Why so prevalent? Why so prevalent? Consumer interest in eating RAW foods Consumer interest in eating RAW foods Grocery Foods mass produced at Grocery Foods mass produced at –Processing plants (see Food Inc. ~ the movie)  Malfunction Ice Cream Plant in Minnesota  240,000 Salmonella Bacteria infections~ ice cream: Ready to eat foods (foreign countries) e.g. Ready to eat foods (foreign countries) e.g. –Berries (Guatemala) –Seafood (Asia) Anti-biotics in animal feeds Anti-biotics in animal feeds –bacteria develp anti-biotic resistant strains  Can grow even if exposed to typical antibiotic

5 Food Safety Agencies

6 Preservation of Food Preventing growth of bacteria Preventing growth of bacteria –Salt, sugar, smoke, fermentation, drying –Limit water available for bacteria growth Pasteurization, sterilization, refrigeration, freezing, irradiation, canning, chemical preservation Pasteurization, sterilization, refrigeration, freezing, irradiation, canning, chemical preservation Aseptic processing Aseptic processing Pasteurized: MILK & O.J. Packaging using sterile conditions, kill all microbes (heat or chemical etc.)

7 Food Irradiation (symbol on right) (X-rays, UV-rays) - Does not make food radioactive (X-rays, UV-rays) - Does not make food radioactive Breaks down chemical bonds, cell walls, DNA Breaks down chemical bonds, cell walls, DNA Controls growth of insects, bacteria, fungi, parasites Controls growth of insects, bacteria, fungi, parasites Approved for use for raw meats, shell eggs, seeds, dried seasonings Approved for use for raw meats, shell eggs, seeds, dried seasonings Safe according to FDA? ~ free radicals generated.. Safe according to FDA? ~ free radicals generated.. Radura symbol required Radura symbol required Used in many countries, although still controversial Used in many countries, although still controversial

8 Why Are Microbes So Harmful? e.g. Bacillus, Campylobacter, Clostridium, Vibrio, Salmonella Bacteria everywhere: 1 tsp. soil = 2 billion Bacteria !!! Challenge Question What are the TWO Ways that microbes cause food borne illness? Shiga Toxin

9 Microorganisms and Food Borne Constant risk Constant risk of foodborne illness

10 Animation Microbial Growth vs Temp. & Temperature vs Spoilage Take Break

11

12 Food Additives? Limit spoilage Limit spoilage Prevent undesirable changes in color & flavor Prevent undesirable changes in color & flavor Increase safety of food distribution Increase safety of food distribution

13 Food Additive Classifications Intentional food additives Intentional food additives –Added directly to food e.g. (Yellow #5, BHT, sulfites, vit. C) Incidental food additives Incidental food additives –Indirectly added as contaminant (e.g., pesticide residues, rat poo) Both are regulated by FDA Both are regulated by FDA

14 Confirming your knowledge What 4 compounds constitute 98% of all additives used in food processing (by weight)? What 4 compounds constitute 98% of all additives used in food processing (by weight)?

15 GRAS (Generally Recognized As Safe) List Manufacturers do not have to prove safety Manufacturers do not have to prove safety –Already regarded as safe, FDA FDA –Responsible for proving that a substance does not belong on GRAS list  red dye #3 removed (carcinogen) Synthetic chemicals ≤ toxicity of natural products (Organic/ Natural ≠ safer) Synthetic chemicals ≤ toxicity of natural products (Organic/ Natural ≠ safer)

16 Safety of Additives Tested on at least 2 animal species Tested on at least 2 animal species –Mice, rats Determine the highest dose that produces no observable effects (skin, inflammation etc. Determine the highest dose that produces no observable effects (skin, inflammation etc. Prorate dose to a human dose (1% of toxicity~ mice) Prorate dose to a human dose (1% of toxicity~ mice) –Divide dose by 100 to establish margin of safety If additive is shown to cause cancer even at very high dose, it is taken off the market by FDA If additive is shown to cause cancer even at very high dose, it is taken off the market by FDA –Several exceptions (nitrates, nitrites  nitrosamines)

17 -Challenge Question- What is the Delaney Clause? And what are exceptions?

18 FDA Approval for New Food Additive Must identify new additive Must identify new additive Give its chemical composition Give its chemical composition State how it is manufactured State how it is manufactured Specify method of measurement Specify method of measurement Outline intended purpose Outline intended purpose Provide proof of safety Provide proof of safety Cannot to be used to deceive public Cannot to be used to deceive public

19 Types of Food Additives Aspartame

20 Nitrates/Nitrites Proven to cause cancer Still used b/c risk is low..

21 High Fructose Corn Syrup (HFCS) ~ high levels of Mercury (Hg) ~ High levels of Carbonyl compounds (Methylglyoxal) -shown to be high in people w/ Diabetes Soda Warning? New Study Supports Link Between Diabetes, High-fructose Corn Syrup 13-Aug-2007, Source: American Chemical Society (ACS) - Newswise (MSG) USDA/FDA Recomendataion: -eat foods of HFCS in moderation...

22 Confirming your knowledge What is the permissible % amount of a food additive that has shown toxicity to laboratory animals that can be added to food? What is the permissible % amount of a food additive that has shown toxicity to laboratory animals that can be added to food?

23 Natural Toxins Occur naturally in foods Occur naturally in foods Safrole from sassafras, mace, nutmeg, cinnamon Safrole from sassafras, mace, nutmeg, cinnamon –(used in Root beer) Known carcinogen – Banned by FDA Solanine from potato shoots Solanine from potato shoots –NIH on solanine: never eat potatoes green below the skin. –nausea, diarrhea, vomiting, Mushroom toxins (phalloidin) Mushroom toxins (phalloidin) –Death cap mushroom –Amanita phalloides Avidin Avidin Tetrodotoxin Tetrodotoxin Oxalic acid Oxalic acid Herbal teas Herbal teas Safrole solanine phalloidin

24 IS Caffeine a Cause for Concern? Causes anxiety, dehydration, insommnia, increased heart rate Causes anxiety, dehydration, insommnia, increased heart rate Cancers? Cancers? Worsens heartburn (relaxes sphincter muscles in esophagus) Worsens heartburn (relaxes sphincter muscles in esophagus) Women ~500mg/day increased miscarriages Women ~500mg/day increased miscarriages –FDA: pregnant women ≤ 2 8oz coffee cup/day Improves performance in top athletes Improves performance in top athletes mg/day prudent dose, (2 cups coffee/day) mg/day prudent dose, (2 cups coffee/day) –safe/sound for now theobromine caffeine

25 Environmental Toxins

26 Pesticides vs Organic Most healthy authorities believe benefits Most healthy authorities believe benefits Outweigh risks (pesticide usage) Most toxicity due to chronic vs acute cases Most toxicity due to chronic vs acute cases –extremely small exposure levels avg. human Growing evidence (contamination, destruction of wildlife habitats) Growing evidence (contamination, destruction of wildlife habitats) –N. Americans should reduce pesticide use –(USDA + farmers working towards)

27 What is a pesticide? Any substance/mixture intended to prevent, destroy, repel or mitigate any pest. Any substance/mixture intended to prevent, destroy, repel or mitigate any pest. EPA allows 10,000 pesticides EPA allows 10,000 pesticides –(300 active ingredients) Benachou et al., " Glyphosate Formulations Induce Apoptosis and Necrosis in Human Umbilical, Glyphosate Formulations Induce Apoptosis and Necrosis in Human Umbilical, Embryonic, and Placental CellsEmbryonic, and Placental Cells 2008, Chemical Research in Toxicology glyphosate e.g. Roundup: (glyphosate) -most used herbicide in the USA - #1 selling in world, toxicity to developing embryos

28 Not all pesticides = bad e.g. fungicides prevent aflatoxin e.g. fungicides prevent aflatoxin –By product of fungal growth  Most potent Deadly carcinogens -Pesticides prevent billions of food crops destroyed annually aflatoxin

29 How safe are Pesticides? Toxicity based on chronic exposures Toxicity based on chronic exposures –Increased cancer in farm communities  Lymph, genital, brain, digestive cancers Some argue pesticide laden food = safer Some argue pesticide laden food = safer vs natural product toxins e.g. peanut butter (aflatoxin) aflatoxin

30 Confirming your Knowledge How can you Reduce Your Exposure to Environmental Toxins?

31 Water Supply

32 Water Bottled water Bottled water –Artesian –Distilled –Purified –Spring –Mineral Public drinking water Public drinking water Challenge Question- What is a good way to limit heavy metal exposure in tap water from your faucet? Why should you never run Hot water from the Tap to cook with?

33 Avoiding Microbes at the Store Buy frozen, perishable foods last Buy frozen, perishable foods last Place meats in separate plastic bags Place meats in separate plastic bags Don’t buy dented cans Don’t buy dented cans –Clostridium botulinum toxin  Most toxic protein known –LD50 of roughly µg/kg. LD50 –AKA Botox (inhibits Acetylcholine) Buy only pasteurized milk/cheese Buy only pasteurized milk/cheese Buy only what you need (shop 1X week or bi-monthly) Buy only what you need (shop 1X week or bi-monthly) –buy Fresh Avoid buying slimy, brownish, or dry produce Avoid buying slimy, brownish, or dry produce –botulinum toxin

34 Avoiding Microbes At Home Wash hands thoroughly Wash hands thoroughly Keep counters, cutting boards, equipment clean and sanitized Keep counters, cutting boards, equipment clean and sanitized Prepare raw meat separately Prepare raw meat separately Thaw foods in refrigerator/cold running water/ microwave Thaw foods in refrigerator/cold running water/ microwave Avoid coughing and sneezing over food Avoid coughing and sneezing over food Wash fruits/vegetables thoroughly Wash fruits/vegetables thoroughly Remove mold or discard food Remove mold or discard food Use refrigerated meat in 1-2 days; frozen in 3-4 months Use refrigerated meat in 1-2 days; frozen in 3-4 months

35 Avoiding Microbes When Cooking Thoroughly cook meat, fish, poultry, eggs Thoroughly cook meat, fish, poultry, eggs Check for doneness with thermometer Check for doneness with thermometer Cook sprouts until steaming Cook sprouts until steaming Cook stuffing separately Cook stuffing separately Eat food right away Eat food right away Store leftovers within 1-2 hours (bacteria growth) Store leftovers within 1-2 hours (bacteria growth) Serve cooked meat on clean plates Serve cooked meat on clean plates Avoid partially cooking food Avoid partially cooking food

36 Internal Cooking Temperature

37 When in Doubt Throw it out?>

38 What To Do With Leftovers Keep hot foods hot & cold foods cold ( 135° F) Keep hot foods hot & cold foods cold ( 135° F) Reheat leftovers thoroughly Reheat leftovers thoroughly (165° F) Store peeled, cut-up produce in refrigerator Store peeled, cut-up produce in refrigerator Keep refrigerator < 41° F Keep refrigerator < 41° F

39 Assignments Diet Analysis 2 due Wednesday (10 pts.) Diet Analysis 2 due Wednesday (10 pts.) Evaluations Wednesday Evaluations Wednesday Food Inc. Qs (5 pts) Due Friday Food Inc. Qs (5 pts) Due Friday Practice Final Online w/ answers Practice Final Online w/ answers Final Exam this Friday (Chapters 6, 8,9,10,11,13,16) Final Exam this Friday (Chapters 6, 8,9,10,11,13,16) –Challenge & Confirming Your Knowledge Qs (the above) –Old Final know all Qs and answers


Download ppt "Chapter 13 Safety of Food and Water. Foodborne Illness Greatest risk from viral and bacterial contamination: Greatest risk from viral and bacterial contamination:"

Similar presentations


Ads by Google