Chapter 12 Food Safety and Food Technology

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Chapter 12Food Safety and Food Technology
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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

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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

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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

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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

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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 0157H7
• 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

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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

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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 nations total food-poisoning
  cases each year
• The vast majority of cases arise from one
  persons error in a small setting
• Affect just a few victims

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Food Safety

• Food can provide ideal conditions for bacteria to
  thrive or produce toxins
• Disease-causing bacteria require
• Warmth
• 40F - 140F 4C - 60C
• 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

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Food Safety

• Keep Hot Food Hot
• Keep cooked foods at 140F 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

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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

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Food Safety

• Treat kitchen utensils with heat
• Soapy water heated to 140F 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

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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

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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 bodys immune system doesnt 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

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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

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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

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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

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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

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Illness When Traveling

• People who travel to places where cleanliness
  standards are lacking can get Travelers 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

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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

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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

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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

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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

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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

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Irradiation and Food Safety

• Irradiations 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

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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

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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

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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

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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

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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

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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

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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

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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

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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

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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

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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)

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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

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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

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Effects of Food Processing Freezing

• Lowers the foods 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
  0F, 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

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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

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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

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Food Additives

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

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Food Additives Antimicrobial Agents--Preservative
s

• 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

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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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Food Additives

• 9. Incidental
• Include bits of plastic, glass, paper, tin from
  packages and chemicals from processing, such as
  solvents used to decaffeinate coffees
• Dioxins are found in coffee filters, paper milk
  cartons, paper plates, and frozen food boxes made
  of bleached paper
• 10. Nutrients
• Iodine added to salt
• Vitamins A and D added to dairy products
• Nutrients used to enrich and fortify breakfast
  cereals and grains
• Vitamins C and E used as antioxidants
• Beta-carotene as a colorant

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Regulations Governing Additives

• The GRAS list (generally recognized as safe)
• A list of 700 substances that were used routinely
  without any problems for many years. When
  substantial scientific evidence or public outcry
  has questioned the safety of a GRAS list additive
  its safety has been reevaluated by FDA.

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Preserving Nutrients in Foods

• Conserving Nutrients at Home
• In modern commercial processing, losses of
  vitamins seldom exceed 25
• Losses of 60 - 75 can occur during food
  preparation at home
• Enzymes can cause destruction of vitamins
• Breakdown of nutrients in fresh fruits and
  vegetables occurs at room temperature (70F).
  Chilling slows the breakdown.
• Light and air cause the breakdown of some
  vitamins-Riboflavin is light sensitive (milk)
• Refreezing causes texture and taste changes and
  loss of nutrient content

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Preserving Nutrients in Foods

• Minerals and water-soluble vitamins in
  vegetables dissolve in water in which they are
  washed, boiled, or canned
• As much as half of the vitamins and minerals in
  foods go down the drain with the water
• Ways to minimize cooking losses
• Steam, stir-fry or microwave vegetables
• Use the liquid in soup or stews

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Controversy Organic Foods And Genetically
Modified Foods What Are The Pros and Cons?

• Organic food is one of the fastest growing
  segments of the food industry
• At the same time, many U.S. farms have shifted
  toward growing foods altered through genetic
  engineering (GE)
• 80 of soybeans, 40 of corn, 70 of cotton
• Issues Surrounding Organic Foods
• A farmer wishing to grow and market organic foods
  must receive certification by USDA inspectors
• Food sold or labeled as organic, must be
  processed according to the procedures outlined in
  the following slide

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Organic Foods

• Environmental Benefits
• Organic foods are grown by using the techniques
  of sustainable agriculture
• Vegetables and fruits are fertilized with
  composted animal manure or vegetable matter with
  no synthetic fertilizers that can run off into
  waterways and pollute them
• No synthetic pesticides or disease-fighting
  agents are applied
• Chemical impact on wildlife and humans is minimal

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Organic Foods

• Potential Health Risks
• Organic foods may not be safer than conventional
  foods
• Improperly composted manure fertilizer may expose
  consumers to microbial diseases
• Unpasteurized organic juices, milk, and cheeses
  may be microbial hazards
• Lack of preservatives causes more spoilage
• Costs
• Organic foods cost more than conventional foods

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Genetically Modified Foods

• Like organic food production, genetic engineering
  carries its own potential set of risks and
  rewards
• Unlike the tried and true organic foods, GE food
  varieties are new to the food supply

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• Genetic Engineering
• The consumer may not be able to distinguish
  genetically altered food from food that has not
  been genetically altered because it bears no
  special labels

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Genetically Modified Foods

• Benefits of genetic engineering
• Enhanced plant growth
• Reduced pesticide and fertilizer use
• Enhanced nutrient composition
• Enhanced crop yields
• Risks
• Potential for new allergens
• Herbicide resistant weeds
• Loss of biodiversity

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Genetically Modified Foods

• Genetic Engineering Basics
• Genetic engineering can change the genetic makeup
  of an organism in a year or two
• Cross-breeding in nature and selective breeding
  in agriculture, is a lengthy process

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Genetically Modified Foods

• Plant genetics
• Traditional breeding
• Cross two plants, develop hybrids, takes time
• Genetic engineering
• Transform specific genes
• Less time to get desiredeffects

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Genetically Modified Foods

• The Promises of Genetic Engineering
• Supporters see it as a means of overcoming many
  of the planets pressing problems, such as
• Food shortages
• Nutrient deficiencies
• Medicine shortages
• Dwindling farmland
• Environmental degradation

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Genetically Modified Foods

• New crops can now resist insects without sprays
• Survive drought
• Provide more complete sources of protein for
  people without access to animal products or
  adequate vegetable proteins

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Genetically Modified Foods

• GM Microorganisms can change production of foods
• Bacteria can make the enzyme rennin needed in
  cheese production
• In the past rennin was obtained from the stomachs
  of calves
• GM bacteria produces human growth hormone
• More children with growth hormone deficiency can
  grow normally
• Others GM bacteria produce the hormone insulin

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Genetically Modified Foods

• The current manufacturing process of fortifying
  and enriching wheat, rice, grains, and milk
  products may become obsolete if rDNA added to
  plants and animals can make the extra nutrients
  in their tissues
• Consumers may see favorite foods such as potatoes
  turned into functional foods that contain
  phytochemicals borrowed from foods such as
  flaxseed

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Genetically Modified Foods

• Opposition to Biotechnology
• Some fear that by tampering with the basic
  blueprint of life, genetic engineering will
  sooner or later unleash mayhem on an unsuspecting
  world
• Opponents view biotechnology firms as naïve and
  profit driven
• Proponents of genetic engineering respond that
  most of the worlds people cannot afford the
  luxury of rejecting the benefits of technology

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Genetically Modified Foods

• Opponents point out that while rDNA technology
  benefits biotechnology companies and giant
  industrial farms, it has produced no real
  benefits for consumers and the risks are not
  defined
• Others object to rDNA technology on religious
  grounds
• Holding that genetic decisions are best left to
  nature or a higher power

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