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Chapter 12. Food Safety and the Global Food Supply. Ask Yourself. Pesticides rank as the number one hazard in the U.S. food supply. The most frequent cause of foodborne illness in homes and restaurants is inadequate cooling of foods.
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Chapter 12 Food Safety and the Global Food Supply © 2007 Thomson - Wadsworth
Ask Yourself • Pesticides rank as the number one hazard in the U.S. food supply. • The most frequent cause of foodborne illness in homes and restaurants is inadequate cooling of foods. • If a food contains a toxic substance, a person who eats it will become ill. • Tainted mayonnaise frequently causes food poisoning. • Imported foods may contain residues of pesticides that are illegal in the United States. © 2007 Thomson - Wadsworth
Ask Yourself • A USDA rule on organic crops allows the use of genetically-engineered ingredients and irradiation in organic foods. • Hunger in the United States afflicts almost exclusively underemployed homeless people. • Legal pesticides are poisonous only to pests, not to people. • Most foods that cause food poisoning are contaminated by the manufacturer or processor. • Food additives are a major cause of cancer in the United States. © 2007 Thomson - Wadsworth
Foodborne Illnesses and the Agents that Cause Them • Foodborne illness:illness occurring as a result of ingesting food or water contaminated with a poisonous substance, such as: • A toxin or chemical (food intoxication) …or an infectious agent such as: • Bacteria • Viruses • Parasites (foodborne infection) • Commonly called food poisoning. © 2007 Thomson - Wadsworth
Foodborne Illnesses and the Agents that Cause Them • Pasteurization:the process of sterilizing food via heat treatment. • Food intoxication: illness caused by eating food that contains a harmful toxin or chemical. • Enterotoxin:a toxic compound, produced by micro-organisms, that harms mucous membranes, as in the gastrointestinal tract. • entero = intestine • Neurotoxin:a poisonous compound that disrupts the nervous system. • neuro = nerve • Foodborne infection:illness caused by eating a food containing bacteria or other microorganisms capable of growing and thriving in a person’s tissues. © 2007 Thomson - Wadsworth
Foodborne Illnesses and the Agents that Cause Them © 2007 Thomson - Wadsworth
Foodborne Illnesses and the Agents that Cause Them • Handle raw meat and poultry with care and cook it thoroughly to destroy any bacteria present. • Place it on a clean plate when it is cooked. © 2007 Thomson - Wadsworth
Foodborne Illnesses and the Agents that Cause Them • Aflatoxin: a poisonous toxin produced by molds. • Toxicants: poisons, that is, agents that cause physical harm or death when present in large amounts. © 2007 Thomson - Wadsworth
Safe Food Storage and Preparation • Keep Cold Foods Cold • Store foods in a refrigerator set at 40 degrees; freezer at 0 degrees. • Thaw frozen food on a plate in the refrigerator; or microwave as part of the cooking process. • Wash Hands and Surfaces Often • Wash hands in warm, soapy water before beginning food preparation. • Wash hands again after handing meat, poultry or fish. • Keep countertops, and kitchen equipment clean with hot, soapy water. © 2007 Thomson - Wadsworth
Safe Food Storage and Preparation • Keep Hot Foods Hot • Cook foods thoroughly to destroy any bacteria that is present. • Keep foods hot until serving. • Never leave food at room temperature for more than 2 hours. • Refrigerate leftovers. • Prevent cross-contamination:the inadvertent transfer of bacteria from one food to another that occurs, for instance, by chopping vegetables on the same cutting board used to skin poultry. © 2007 Thomson - Wadsworth
Safe Food Storage and Preparation • Food Safety for Meats • Ground meat is especially susceptible to bacterial contamination. • Cook to a well done stage and use a meat thermometer. • Food Safety for Seafood • Seafood should be handled with care, especially fish intended to be eaten raw. • Because of risk of contamination, the hazards of eating raw or undercooked seafood need to be weighed carefully, especially by vulnerable people, including those with liver disease, gastrointestinal disorders, HIV infection and other diseases that compromise the immune system. © 2007 Thomson - Wadsworth
Safe Food Storage and Preparation • Mad cow disease (bovine spongiform encephalopathy or BSE): a rare and fatal degenerative disease first diagnosed in 1986 in cattle in the United Kingdom. • The bovine disease may be passed to humans who eat the meat of infected animals and may lead to death due to brain and nerve damage. © 2007 Thomson - Wadsworth
Safe Food Storage and Preparation © 2007 Thomson - Wadsworth
Pesticides and Other Chemical Contaminants • Contaminants: potentially dangerous substances, such as lead, that can accidentally get into foods. © 2007 Thomson - Wadsworth
Pesticides and Other Chemical Contaminants • Organic halogens: compounds that contain one or more of a class of atoms called halogens, including fluorine, chlorine, iodine, or bromine. • Heavy metals: any of a number of mineral ions, such as mercury and lead, so named because of their relatively high atomic weight. • Many heavy metals are poisonous. • Toxicity: the ability of a substance to harm living organisms. • All substances are toxic if present in high enough concentrations. • Hazard: state of danger; used to refer to any circumstance in which harm is possible. © 2007 Thomson - Wadsworth
Pesticides and Other Chemical Contaminants © 2007 Thomson - Wadsworth
Pesticides and Other Chemical Contaminants • Pesticides: chemicals applied intentionally to plants, including foods, to prevent or eliminate pest damage. • Pests include all living organisms that destroy or spoil foods: • Bacteria • Molds • Fungi • Insects • Rats and other rodents … to name a few. © 2007 Thomson - Wadsworth
Pesticides and Other Chemical Contaminants • Regulation: a legal mandate that must be obeyed. • Failure to follow a regulation brings about serious legal consequences. • Foods imported from other countries may harbor residues of pesticides that have been banned for use in the United States. © 2007 Thomson - Wadsworth
Pesticides and Other Chemical Contaminants • Risk: the harm a substance may confer. • Scientists estimate risk by assessing the amount of a chemical that each person in a population might consume over time (also called exposure) and by considering how toxic the substance might be (toxicity). • risk = exposure x toxicity • exposure = amount of substance in food x amount of food eaten • Tolerance: the maximum amount of a particular substance allowed on food. • Reference dose: the estimated amount of a chemical that could be consumed daily without causing harmful effects. © 2007 Thomson - Wadsworth
Margin of safety: from a food safety standpoint, the margin is a zone between the maximum amount of a substance that appears to be safe and the amount allowed in the food supply. © 2007 Thomson - Wadsworth
Pesticides and Other Chemical Contaminants © 2007 Thomson - Wadsworth
Food Additives • Food additive: any substance added to food, including substances used in the production, processing, treatment, packaging, transportation, or storage of food. • Intentional food additives: substances intentionally added to food. Examples include: • Nutrients • Colors • Spices • Herbs • Incidental food additives (or indirect additives): substances that accidentally get into food as a result of contact with it during growing, processing, packaging, storing, or some other stage before the food is consumed. © 2007 Thomson - Wadsworth
Food Additives • GRAS (Generally Recognized As Safe): a list of ingredients, established by the FDA, that had long been in use and were believed safe.The list is subject to revision as new facts become known. • Delaney clause: a provision in the 1958 Food Additives Amendment that prohibited manufacturers from using any substance that was known to cause cancer in animals or humans at any dose level. © 2007 Thomson - Wadsworth
Should You Buy Organically Grown Produce or Meats? • Organically grown foods: crops or livestock grown and processed according to USDA regulations concerning use of pesticides, herbicides, fungicides, fertilizers, preservatives, other synthetic chemicals, growth hormones, antibiotics, or other drugs. • Integrated pest management: the use of biological controls, crop rotation, genetic engineering, and other tactics to reduce chemical use in the growing of crops. © 2007 Thomson - Wadsworth
In October 2002, food labels • began to regulate the term • “organic” on foods grown in • the United States. To use • USDA organic seal: • Raw products must be • 100% organic. • Processed foods must • contain 95% organic • ingredients. © 2007 Thomson - Wadsworth
Why Choose a Farmer’s Market? • They help develop a food culture. • Foods are less processed and less packaged. • Foods are usually fresher. • Encourages healthier food choices by promoting seasonal fruits and vegetables. • Boosts the local economy. © 2007 Thomson - Wadsworth
New Technologies on the Horizon • Irradiation: the process of exposing a substance to low doses of radiation, using gamma rays, X-rays, or electricity (electron beams) to kill insects, bacteria, and other potentially harmful microorganisms. • Unique radiolytic products: substances unique to irradiated food and apparently created during the process of irradiation. © 2007 Thomson - Wadsworth
New Technologies on the Horizon • The FDA requires that the labels of all irradiated foods carry this internationally known radura symbol for irradiation. • The circle in the middle represents an energy source; the five breaks in the outer circle symbolize rays generated by the energy source; and the two petals signify food. © 2007 Thomson - Wadsworth
New Technologies on the Horizon Farmers bred corn as we know it today from wild corn © 2007 Thomson - Wadsworth
New Technologies on the Horizon • Genetic engineering: the process of altering the genes of a plant in an effort to create a new plant with different traits. • This process of recombining genes is also known as recombinant DNA (rDNA) technology; a form of biotechnology. • Transgenetics: the process of transferring genes from one species to another unrelated species. • Biotechnology: the science that alters the composition and characteristics of biological systems, organisms, or foods by manipulating their genetic makeup. © 2007 Thomson - Wadsworth
Potential Benefits: Increased nutritional value of staple foods Reduced environmental impact Increased fish yield Increased nutrient absorption by livestock Tolerance of poor environmental conditions Potential Risks: Inadequate controls Transfer of allergens Unpredictability Undesired gene movement Environmental hazards Benefits/Risks of Genetic Engineering © 2007 Thomson - Wadsworth
Domestic and World Hunger • Infants can be the first to show the signs of undernutrition due to their high nutrient needs. • No famine, no flood, no earthquake, no war has ever claimed the lives of 250,000 children in a single week. • Yet malnutrition and disease claim that number of child victims every week. © 2007 Thomson - Wadsworth
Domestic and World Hunger • Food security: access by all people at all times to enough food for an active, healthy life and at a minimum includes the following: • The ready availability of nutritionally adequate and safe foods. • The ability to acquire personally acceptable foods in a socially acceptable way. • Hunger is related to poverty. • Food is available but is not accessible to the poor who have neither land nor money. © 2007 Thomson - Wadsworth
Feeding the hungry—in the U.S. © 2007 Thomson - Wadsworth
Domestic and World Hunger • Food banks: nonprofit community organizations that collect surplus commodities from the government and edible but often unmarketable foods from private industry for use by nonprofit charities, institutions, and feeding programs at nominal cost. • Poverty: the state of having too little money to meet minimum needs for food, clothing, and shelter. The U.S. Department of Agriculture defines the poverty level in the United States as an annual income of $19,350 for a family of four. • Second harvest: a national food banking network to which the majority of food banks belong. • Multinational corporations: international companies with direct investments and/or operative facilities in more than one country. U.S. oil and food companies are examples. © 2007 Thomson - Wadsworth