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The science of nutrition 4th edition thompson manore vaughan chapter 15

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Chapter 15 Lecture Chapter 15: Food Safety and Technology: Protecting Our Food © 2017 Pearson Education, Inc Foodborne Illness • Symptom or disorder from food or water contaminated with pathogenic microorganisms, it's toxic secretions, or a toxic chemical • Commonly called food poisoning • According to CDC, 48 million Americans experience foodborne illness each year • Major public health concern in recent years © 2017 Pearson Education, Inc Body Responses to Contaminants • Antimicrobial enzymes in saliva and hydrochloric acid in the stomach kill some contaminants • Vomiting and diarrhea effectively expel offenders • White blood cells activate immune response © 2017 Pearson Education, Inc People at Risk • Developing fetuses, infants, and young children, whose immune systems are still immature • Pregnant women • The very old and the frail elderly • People with chronic illnesses (e.g., diabetes) • People with acquired immunodeficiency syndrome (AIDS) • People who are receiving immune-systemsuppressing drugs (e.g., transplant recipients and cancer patients) © 2017 Pearson Education, Inc Foodborne Illness Challenges • Substantial and increasing portion of U.S food supply is imported • Regulation and oversight in country of origin may be inadequate • Produce is responsible for greatest percentage of foodborne illness, but meat and poultry are responsible for the greatest percentage of deaths • U.S federal oversight of food safety is fragmented (USDA, FDA, CDC, EPA) © 2017 Pearson Education, Inc © 2017 Pearson Education, Inc Causes of Foodborne Illness • Food intoxications: consuming food in which microbes have secreted harmful substances called toxins • Naturally occurring toxins (plant and marine) • Chemical residues • Viruses • Bacteria • Parasites • Fungi © 2017 Pearson Education, Inc © 2017 Pearson Education, Inc Microorganisms Contaminate Food • Bacteria and viruses are the most common microorganisms causing foodborne illnesses • Viruses: Norovirus and Hepatitis A virus (HAV) • Norovirus is most common cause of foodborne illness in U.S • Most common bacterial contaminant: • Salmonella: second leading cause of foodborne illness, causes the most deaths © 2017 Pearson Education, Inc Norovirus â 2017 Pearson Education, Inc The USDA requires Radura – the international symbol for irradiated food © 2017 Pearson Education, Inc Food Additives: Nutrients and Preservatives • Added vitamins and minerals act as nutrients and preservatives; commonly vitamins E, C, and D, and folate • Preservatives of concern are: • Sulfites Nitrates â 2017 Pearson Education, Inc Other Food Additives • Can be natural or synthetic, and include: • Flavor enhancers • Colorings • Texturizers • Emulsifiers • Humectants Dessicants â 2017 Pearson Education, Inc â 2017 Pearson Education, Inc Safety of Food Additives • 1958: Delaney Clause • 1958: Generally Recognized as Safe (GRAS) list 1985: Adverse Reaction Monitoring System (ARMS) â 2017 Pearson Education, Inc Genetic Modification • Also called genetic engineering; alters the DNA of an organism (plant or animal) to acquire specific changes in seeds or offspring • Examples include: • Selective breeding • Recombinant DNA technology • Genetically Modified Organisms (GMOs) = organisms that have had their DNA altered using this technology • In 2014, 89% of all corn crops and 94% of all soybean crops in the U.S were herbicide-tolerant GMOs © 2017 Pearson Education, Inc © 2017 Pearson Education, Inc 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; health concern • Heavy metals: mercury and lead are neurotoxic • Plasticizers: BPA in cans and plastic bottles • Industrial pollutants • Polyfluorinated chemicals: PFAs degrade very slowly © 2017 Pearson Education, Inc © 2017 Pearson Education, Inc Pesticides • Pesticides: protect against weeds, insects, fungi; increase crop yields • Insecticides, herbicides, fungicides • Can be natural (biopesticides) or synthetic (glyphosate or Roundup) • Remain on foods, causing health risk, are carcinogenic • Children: especially sensitive to pesticides • EPA controls use of pesticides © 2017 Pearson Education, Inc 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: methicillinresistant Staphylococcus aureus (MRSA) Promotes spread of anti-biotic resistant infections â 2017 Pearson Education, Inc Organic Agriculture • Foods grown without toxic and persistent fertilizers and pesticides • Standards regulated by USDA • Organic foods are safer but not necessarily more nutritious © 2017 Pearson Education, Inc © 2017 Pearson Education, Inc © 2017 Pearson Education, Inc ABC News Video: FDA Proposes New Food Safety Rules © 2017 Pearson Education, Inc ... responsible for the greatest percentage of deaths • U.S federal oversight of food safety is fragmented (USDA, FDA, CDC, EPA) © 2017 Pearson Education, Inc © 2017 Pearson Education, Inc Causes of Foodborne... and increasing portion of U.S food supply is imported • Regulation and oversight in country of origin may be inadequate • Produce is responsible for greatest percentage of foodborne illness, but... contaminant: • Salmonella: second leading cause of foodborne illness, causes the most deaths â 2017 Pearson Education, Inc Norovirus â 2017 Pearson Education, Inc The salmonella bacterium © 2017 Pearson

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