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Chapter 12 Food Safety and Food Technology

Chapter 12 Food Safety and Food Technology. Agencies That Monitor The U.S. Food Supply. CDC (Center for Disease Control and Prevention) Dept. Health and Human Services-monitors foodborne illness EPA -regulates pesticides and water quality

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Chapter 12 Food Safety and Food Technology

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  1. Chapter 12Food Safety and Food Technology

  2. Agencies That Monitor The U.S. Food Supply • CDC (Center for Disease Control and Prevention) Dept. Health and Human Services-monitors foodborne illness • EPA-regulates pesticides and water quality • FDA- (HHS) responsible for all food safety and wholesomeness except eggs, meat and poultry • USDA-Responsible for meat, poultry and eggs

  3. Food Safety • Harmful substances in foods Pathogens • Bacteria, viruses, parasites • Some common pathogens causing foodborne illness • Staphylococcus aureus, Clostridium botulinum, Salmonella, Escherichia coli Chemical contamination • Pesticides • Animal drugs • Pollutants Natural toxins • Methyl mercury • Poisonous plants • Solanine

  4. Microbes and Food Safety • Foodborne illnesses can be life-threatening • Especially to the ill, the malnourished, those with a compromised immune system, pregnant women, infants, children and the very old • Each year in the United States, an estimated 76 million people become ill from foodborne diseases ≈5,000 of them die

  5. Microbes and Food Safety Symptoms of foodborne illness • Bloody stools • Diarrhea of more than 3 days’ duration • Fever of longer than 24 hours duration • Headache accompanied by muscle stiffness and fever • Numbness, muscle weakness, tingling sensations in the skin • Rapid heart rate, fainting, dizziness Majority of food-poisoning cases • Result of errors consumers make in handling foods after purchase • Commercially prepared food is “usually” safe If digestive tract disturbances are the only major symptom of your next bout of “stomach flu” chances are it was foodborne illness

  6. Food Safety • Raw meats can contain live, disease-causing organisms • Thorough cooking makes them safe • In the mid-1990s a fast-food restaurant chain in the Northwest served undercooked hamburgers from meat contaminated with bacterium E. coli 0157:H7 • 4 people died • 100s of patrons became seriously ill As a result more Government Inspections and Industry controls were set up through the Hazard Analysis Critical Control Point (HACCP) plan

  7. Food Safety • By law, U.S. producers and handlers of meat, poultry, seafood, fresh fruit, and vegetable juices must employ a Hazard Analysis Critical Control Point (HACCP) plan • Since the implementation contamination of poultry has declined by 50%, ground beef by 40%, pork by 25% • USDA inspectors increased • FDA inspectors decreased

  8. Food Safety • Consumer Protection • The safety of canned and packaged foods sold in grocery stores is controlled through sound food technology practices • Large-scale commercial incidents make up only a fraction of the nation’s total food-poisoning cases each year • The vast majority of cases arise from one person’s error in a small setting • Affect just a few victims

  9. Food Safety • Food can provide ideal conditions for bacteria to thrive or produce toxins • Disease-causing bacteria require • Warmth 40°F - 140°F = 4°C - 60°C • Moisture • Nutrients • To control bacteria • Keep hot food hot-above 140F • Keep cold food cold-below 40F/4C • Keep raw foods separate • Keep your hands and the kitchen clean

  10. Food Safety • Keep Hot Food Hot • Keep cooked foods at 140°F or higher until served cooking does not destroy all bacterial toxins • If handled improperly can cause illness • Cooked foods should be refrigerated immediately or within two hours at the maximum • Keep Cold Food Cold • Start when you leave the grocery store • At home, put foods into the refrigerator or freezer immediately • When defrosting foods • Thaw meats or poultry in the refrigerator • Marinate meats in the refrigerator

  11. Food Safety • Food with an “off” appearance or odor should not be used or tasted • Keep raw foods separate /Prevent cross-contamination • Raw foods, especially meats, eggs and seafood, are likely to contain bacteria • Keep the raw foods and their juices away from ready-to-eat foods • After handling raw foods wash surfaces & your hands, thoroughly with soap • Foods prone to microbial growth • Those high in moisture and nutrients • Those chopped or ground like meats and poultry

  12. Food Safety • Treat kitchen utensils with heat • Soapy water heated to 140°F kills most harmful organisms • Water must be scalding hot, well beyond the temperature of the tap • Automatic dishwasher • Uses water hotter than hands can tolerate • Most dishwasher detergents contain chlorine • Sponges • Place wet sponges in a microwave and heat it until steaming hot • Make use of antibacterial cleaners, sponges, cloths, boards, or utensils

  13. Foods That Make People Sick Cryptosporidium-300,00 ill/7deaths 2-10days 1993/ affected 400,00 100 deaths Milwaukee Hepatitis A-4200 ill/4 deaths 15-58 days Listeria-2,500 ill/500 deaths 7-30 days E. Coli -62,500 ill/50 deaths Salmonella -1-34 million/500 deaths 1-3 days “Stomach Flu”/Norovirus 9.2 million/124 deaths 12-24hr Traveler’ Diarrhea/ Giardia and other protoza 10 million 2 days-several weeks Botulism-60/4 deaths 12-72 hours Staphycoccus 185,000/2 deaths ½ hour-8hr

  14. Foods That Make People Sick • Bovine Spongiform Encephalopathy (BSE) “Mad Cow” Disease • Not related to sanitation • A disease of cattle linked with a rare but fatal human brain disorder • Can lie dormant in the body for many years before symptoms arise • BSE is caused by a protein, known as a prion • Cannot be killed or controlled through cooking or disinfecting • The body’s immune system doesn’t rid the body of them • Little is known about how prions cause diseases • Found in people who consumed products from infected animals • To date: Fewer than 150 people, most in Great Britain have been diagnosed

  15. Foods That Make People Sick • The USDA has enacted protective measures targeting BSE • Prohibiting the use of downer cattle (unable to walk) for human consumption • Increasing BSE testing of cattle at slaughter • At risk are • Imported supplements made from glands of animals often sold as hormone preparations

  16. Foods That Make People Sick • Eggs • Raw, unpasteurized eggs are likely to be contaminated by Salmonella bacteria • Raw pasteurized egg substitutes may contain a few live bacteria • They may not be safe for pregnant women, the elderly, the very young, or those suffering from immune disorders • Raw Produce • Fruits and vegetables are a microbial threat unless they are thoroughly rinsed in running cold water • Ten years ago, meats, eggs, and seafood posed the greatest foodborne illness threat • Today produce equals them

  17. Foods That Make People Sick • Seafood • Worms, Flukes, Viruses, and Naturally occurring toxins • Dangers posed by seafood have grown in recent years • Offshore waters are becoming more polluted • Viruses that cause human diseases have been detected in ≈90% of water off the U.S. coast

  18. Foods That Make People Sick • Honey • Can contain dormant spores of Clostridium botulinum that become active in the human body & produce a toxin • Adults are usually protected • Infants under one year of age should never be fed honey • Picnics, Lunch Bags, and Take-Out Foods

  19. Illness When Traveling • People who travel to places where cleanliness standards are lacking can get Traveler’s diarrhea • Before you travel, ask your physician which medicines to take with you in case you get sick • Wash your hands often with soap and water • Eat raw fruits and vegetables only if you have washed them with your clean hands in boiled water and peeled them yourself • Skip salads • Water, ice, and beverages made from water may be unsafe • Take along disinfecting tablets • Drink only treated, boiled, canned, or bottled beverages without ice • Use when brushing your teeth

  20. Natural Toxins in Foods • Belladonna and hemlock • Plants that are deadly poisons • Sassafras • Contains a cancer-causing agent • Banned from use in commercially produced foods and beverages • Cabbage, turnips, mustard greens, and radishes • Contain small quantities of goitrogens • Compounds that can enlarge the thyroid gland and aggravate thyroid problems

  21. Natural Toxins in Foods • Raw lima beans, cassava & apricot pits • Contain precursors to cyanide • Potatoes • Contain solanine a bitter, narcotic-like substance • Can build up to toxic levels when potatoes are exposed to light during storage • Found in a green layer that develops just below the skin that can be peeled off • Seafood • Contains redtide toxin that occurs during algae blooms • The red tide causes a form of food poisoning that paralyzes the eater

  22. Irradiation and Food Safety • Potential Benefits of Food Irradiation • Kills almost all disease-producing microorganisms present in food • Reduces the incidence of foodborne illness • Reduces the destruction of food by pests • Can kill most microbes even while food is in a frozen state • Irradiated raw poultry is 99.9% free of disease-causing microorganisms, reducing the risk of cross-contamination • Has no effect on most toxins, prions, and microbial spores

  23. Irradiation and Food Safety Foods approved for radiation Citrus fruits, eggs, frozen and fresh meats, mushrooms, potatoes, onions, poultry, spices, strawberries, tomatoes, tropical fruits, wheat Labeling of Irradiated Foods • Required by the FDA • No label is required for foods containing irradiated ingredients and for irradiated foods served in restaurants

  24. Irradiation and Food Safety • Consumer fears about safety • Foods will become radioactive • Foods will lose nutrients • Foods will not be safe to eat • Harmful chemicals will form • People will be endangered-- plant workers, the general population • The environment will be effected

  25. Irradiation and Food Safety • Irradiation’s Effects on Nutrients • Most nutrients, as proteins, fats, carbohydrates, and minerals, survive irradiation intact • Nutrients sensitive to heat treatment, such as the B vitamins and ascorbic acid, are sensitive to irradiation • Irradiation Safety • More than 40 years of research on animals have revealed no toxic effects from eating irradiated foods • Studies of human volunteers who ate a diet composed entirely of irradiated foods found no ill effects

  26. Irradiation and Food Safety Consumers: The Final Authority • Whether irradiated foods will appear in markets depends upon whether consumers choose to buy them • According to a national survey those willing to purchase irradiated foods declined during the past decade from 70% to about 50% • Cost is a big factor

  27. Residues and Contaminants in FoodsPesticides • Chemicals used to control insects, diseases, weeds, fungi, and other pests on crops and around animals • Includes herbicides, insecticides, and fungicides • Used to ensure the survival of food crops • Accumulates in the food chain • Kill pests’ natural predators • Pollute the water, soil, and air

  28. Residues and Contaminants in Foods Pesticides • Do Pesticides on Foods Pose a Hazard to Consumers? • Many pesticides are broad-spectrum poisons that damage all living cells not just pests • Their use poses hazards to the plants and animals and workers involved with pesticide production, transport, and application • High doses of pesticides applied to laboratory animals cause • Birth defects, Sterility, Tumors, Organ damage, Central nervous system impairment • Pesticide residues on agricultural crops can survive processing and may be present in and on foods served to people

  29. Residues and Contaminants in Foods Pesticides • Infants and children may be more vulnerable to adverse effects • Their brains cannot exclude pesticides and other chemicals to the same extent as the adult brain

  30. Residues and Contaminants in Foods Pesticides • A loophole in federal regulations allows companies in the U.S. to make banned pesticides and export them to other countries • The banned pesticides can then return to the U.S. in imported foods

  31. Residues and Contaminants in Foods Pesticides Possible Alternatives to Pesticides • Manage pests by using a combination of natural and biological controls • Natural Pesticides are uses in organic farming • nicotine (tobacco) • psoralens (celery) • Organic foods • Foods grown and processed without the use of synthetic chemicals such as pesticides, herbicides, fertilizers, or without genetic engineering or irradiation

  32. Residues and Contaminants in Foods Animal Drugs • Bovine somatotropin (bST) growth hormone • Produced by genetically modified bacteria • Cattle are injected with growth hormone • FDA considers the practice safe & does not require testing of food products for traces bST use • Promotes lean tissue growth • Increases milk production • The European Union and Canada ban the use of bST for milk cows

  33. Residues and Contaminants in Foods Animal Drugs • Antibiotics in Livestock • Often given as part of a daily feeding regimen • Prevent infections to the animals living in crowded conditions and promotes rapid growth • By law there is a waiting period before slaughter so the drugs break down • Consumers face little threat of getting antibiotics in meats, milk, and eggs • The greater risk is illness from antibiotic-resistant bacteria when animals are treated with daily antibiotics

  34. Environmental Contaminants • Contaminant • Any substance occurring in food by accident or not normally present • Some contaminants resist breakdown in the body and are not metabolized or excreted • Some (mercury) can pass from one species to another and accumulate at higher concentrations (bioaccumulation) • Chemical contaminants of concern in foods • Heavy metals Arsenic, Cadmium, Lead, Mercury, Selenium • Halogens Chlorine, Ethylene dichloride, Iodine, PBB, PCBs, TCE, Vinyl chloride • Others Acrylamide, Antibiotics (in animal feed), DES, Dioxins

  35. Environmental Contaminants • Mercury • All fish have at least trace amounts of mercury and other contaminants (PCBs, dioxins, and DDT) • The FDA and EPA warns of high methylmercury levels in fish and other seafood • They advise all pregnant women, nursing mothers, and young children against eating fish species high in methylmercury

  36. Effects of Food Processing on the Nutrients in Foods Consumers rely on packaged and processed foods On the positive side it makes food safer and gives food a longer useable shelflife by preventing: • Microbial growth • Oxidative changes • Enzyme destruction On the negative side some vitamins and minerals are lost Pasteurization makes milk safe to drink • Worth the nutrient loss • Boxes of milk that can be kept at room temperature have been treated with ultrahigh temperature (UHT)

  37. Effects of Food Processing Extended Shelf Life • Modified atmosphere packaging (MAP) • Perishable food is packaged in a container from which air is removed (vacuum packed) or another gas mixture has been added to exclude oxygen • Slows ripening of fruits and vegetables • Reduces spoilage by mold and bacterial growth • Prevents discoloration of cut vegetables and fruit • Prevents spoilage of fats by rancidity • Slows development of “off” flavors • Slows enzymatic breakdown of vitamins

  38. Effects of Food ProcessingCanning • Protects against microbes but has fewer nutrients • High heat/short time • Fat soluble vitamins and minerals are not effected • Affected Thiamin, Riboflavin and Vitamin C • Minerals and water soluble vitamins are lost in the water

  39. Effects of Food Processing Freezing Lowers the food’s temperature to a point that stops life processes • Microorganisms do not die but remain dormant until the food is thawed • Slows enzymatic reactions • Nutrient contents are similar to those of fresh foods • Often contain more nutrients than fresh fruits and vegetables that have stayed in the produce department • Foods frozen have to be kept solidly frozen at 0°F, to be safe and retain their nutrients • If foods defrost slightly but ice crystals remain - It is probably safe to refreeze the food for later use

  40. Effects of Food Processing Drying • Drying • Preserves food by removing water to inhibit microbial growth • Commercial drying does not cause major nutrient losses • Sulfite additives • Used for drying fruits • Prevent browning • Helps preserve vitamin C • Some people suffer severe allergic reactions when they consume sulfites

  41. Food Additives What are food additives? • Substances added to foods that are not eaten by themselves as foods • Additives give foods desirable characteristics : Color, Flavor, Texture, Stability, Resistance to spoilage • The FDA decides what additives shall be in foods • All are periodically reviewed • None are permanently approved Compared to the unregulated and untested “dietary supplements” sold directly to consumers, the 3,000 food additives in the U.S. are strictly controlled

  42. Food Additives • Antimicrobial agents • Antioxidants • Artificial colors • Artificial flavors, flavor enhancers • Bleaching agents • Chelating agents • Nutrients • Preservatives • Thickening and stabilizing agents

  43. Food Additives Antimicrobial Agents--Preservatives 1.Salt and Sugar --most widely used • Salt is used to preserve meat and fish • Sugar preserves jams, jellies, and canned and frozen fruits • Salt and sugar withdraw water from food -Microbes cannot grow without water 2. Potassium sorbate & sodium propionate • Extend the shelf life of baked goods, cheese, beverages, mayonnaise, margarine 3. Nitrites • Added to meats and meat products to preserve color, enhance flavor, & retard bacterial growth

  44. Food Additives 4. Sulfites • Prevents oxidation in processed foods, alcoholic beverages, and drugs • Were used to keep raw fruits and vegetables in salad bars looking fresh • Banned after a few people experienced dangerous allergic reactions 5. BHA and BHT • Prevent rancidity in baked goods and snack foods 6. Food coloring • makes foods look attractive 7. Artificial flavors - 2,000 flavors and enhancers are approved 8. MSG produces adverse reactions in some people - Flavor enhancer

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