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Learn about food-borne illnesses, government regulations, causes of food contamination, and how to prevent food poisoning. Discover food additives, preservation techniques, and the safety of additives in this comprehensive guide.
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15 Food Safety and Technology: Impact on Consumers
Food-Borne Illness • Symptom or illness from food or water that contains an infectious agent or toxic substance • Commonly called food poisoning • 76 million reported cases each year • Over half unknown or unreported
People at Risk • Developing fetuses, infants, and young children, whose immune systems are still immature • The very old and the frail elderly • People with chronic illnesses (diabetes) • People with acquired immunodeficiency syndrome (AIDS) • People who are receiving immune-system-suppressing drugs (transplant recipients and cancer patients)
Government Regulators • Multiple government agencies are involved in ensuring the safety and quality of the food supply: • U.S. Department of Agriculture (USDA) • U.S. Food and Drug Administration (FDA) • Centers for Disease Control and Prevention (CDC) • U.S. Environmental Protection Agency (EPA)
Public Health Issue • More foods are mass-produced • Combination of ingredients from a much greater number of sources • Contamination can be difficult to trace • Federal oversight has decreased
Causes of Food-Borne Illnesses • Food infections: consumption of food containing living microorganisms • Food intoxications: consuming food in which microbes have secreted poisonous substances called toxins
Microbes Contaminate Food • Bacteria and viruses are the most common microbes causing food-borne illnesses • Most common bacterial contaminants: • Campylobacter jejuni • Salmonella • Viruses: hepatitis A and E, rotaviruses ABC Video E. Coli at Home
Microbes Contaminate Food • Helminths, commonly called worms, include tapeworms, flukes, roundworms • Parasite: benefits from and harms its host (Giardia) • Fungi: plant-like spore-forming organisms (yeasts and molds) • Prion: self-replicating protein particle that causes mad cow disease or bovine spongiform encephalopathy (BSE)
Microbes Release Toxins • Toxins are responsible for illnesses • Neurotoxins damage the nervous system, cause paralysis • Clostridium botulinum: found in bulging cans, foods improperly canned at home, raw honey • Enterotoxins target the gastrointestinal system, cause severe diarrhea and vomiting • Mycotoxins are secreted by fungi
Toxins Without Microbes • Poisonous mushrooms • Marine toxins • Solanine (greening process in potatoes)
Body Defense Mechanisms • Antimicrobial enzymes in saliva • Hydrochloric acid in the stomach • Vomiting or diarrhea to expel the offender • Activate immune system: white blood cells • To diagnose a food-borne illness: obtain and culture a specimen • Keep the person hydrated and comfortable
Microbes Multiply in Foods • Temperature: 40−140°F (4−60°C) is known as the “danger zone” • Humidity • Acidity • Oxygen content
Preventing Food-Borne Illness When preparing foods at home, be sure to: • Wash hands and kitchen surfaces often • Separate foods to prevent cross-contamination • Chill foods to prevent microbes from growing • Cook foods to their proper temperature
Preventing Food-Borne Illness • Standard rule for storing leftovers: 2 hours/2 inches/4 days • Foods should be cooked thoroughly • Food should be thawed in the refrigerator • When traveling: avoid raw foods, choose bottled water without ice
Preserving Food • Natural methods • Salting • Sugaring • Drying • Smoking • Cooling
Preserving Food • More modern techniques include: • Industrial canning • Packaging techniques (aseptic) • Preservatives (antioxidants, mold inhibitors, sulfites, nitrites, nitrates) • Irradiation • Genetic modification
Food Additives • Natural or synthetic • Flavoring agents • Colorings • Nutrients • Improve texture or moisture content
Food Additives • Flavoring agents: essential oils, extracts, or spices • Flavor enhancers: do not have flavor of their own • Examples include maltol and MSG
Food Additives • Food colorings • Natural colorings beet juice (red color), beta-carotene (yellow), caramel (brown) • Tartrazine (FD&C yellow #5) causes an allergic reaction in some people, and its use must be indicated on the product packaging
Food Additives • Vitaminsandother nutrients: • Vitamins E and C (ascorbic acid): antioxidant • Iodine (table salt) helps to decrease goiter • Vitamin D and calcium for bone health • Folate (breads, cereals) to decrease neural tube defects during fetal development
Food Additives • Texturizers, stabilizers, or emulsifiers to improve the texture of foods • Thickening agents • Humectants maintain correct moisture levels • Desiccants prevent moisture absorption from the air
Safety of Food Additives • Delaney Clause • Generally Recognized as Safe (GRAS) list • Adverse Reaction Monitoring System (ARMS)
Food Residues • Food residues: chemicals that remain in foods despite cleaning and processing • Persistent organic pollutants (POPs): chemicals released into the atmosphere from industry, agriculture, automobiles • Mercury and lead: neurotoxins • Industrial pollutants
Pesticides • Pesticides: protect against weeds, insects, fungi; increase crop yields • Insecticides, herbicides, fungicides • Can be natural or synthetic • Remain on foods, causing health risk • Children: especially sensitive to pesticides • EPA controls use of pesticides
Growth Hormones • Recombinant bovine growth hormone (rBGH): genetically engineered growth hormone given to cows • Increases muscle mass; decreases fat • Increases milk output • Causes mastitis in cows, resulting in increased antibiotic use in the cows • Antibiotic-resistant bacterial strain: methicillin-resistant Staphylococcus aureus (MRSA)
Organic Foods • Food grown without synthetic pesticides • Standards regulated by USDA • May have higher nutrient content • Insufficient evidence to support the claim that organic foods are more nutritious than non-organic foods