Today s Topic. Food Safety. Food Safety. Food Safety and Technology: Microbial Threats and Gene<c Engineering 11/13/15

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1 Today s Topic and Technology: Microbial Threats and Gene<c Engineering Gene<cally Modified Foods BIOL 103, Chapter 14 Harmful substances in foods Pathogens (disease- causing) Foodborne illness: 1. Infec<on from pathogen 2. Toxin produced by microorganism CDC: 48 million Americans become sick, 128,000 require hospitaliza<on, and 3,000 die from foodborne illnesses). Harmful substances in food pathogens (Table 14.1: Common Foodborne Pathogens and Illnesses): Pathogens Common Source Illness Symptoms S. aureus Toxins from S. aureaus contaminated foods C. botulinum Improperly canned foods and contaminated honey Salmonella Undercooked and contaminated poultry/eggs E. coli Raw or undercooked meat, vegetables, contaminated water Vomi<ng, abdominal cramps Fatal to infants Diarrhea, Vomi<ng, Abdominal cramps Watery or bloody diarrhea, Death 1

Prions: self- reproducing protein par<cles that can cause a disease such as Mad Cow Disease or Bovine spongiform encephalopathy (BSE) Mad Cow Disease Diseased prions induce

- Harmful Substances in Food Mad Cow Disease Feeding prac<ces doesn t help: Recycling dead animals into livestock feed increase risks spreading of abnormal prions Cooking and

2 Prions: self- reproducing protein par<cles that can cause a disease such as Mad Cow Disease or Bovine spongiform encephalopathy (BSE) Mad Cow Disease Diseased prions induce healthy (prion) proteins to change their shape (from alpha helix to beta sheets), and clusters of disease build, leaving holes in the brain. - Harmful Substances in Food Mad Cow Disease Feeding prac<ces doesn t help: Recycling dead animals into livestock feed increase risks spreading of abnormal prions Cooking and irradia<on do not kill or deac<vate abnormal prions. Chemical contamina<on Pes<cides Important role in food produc<on Concerns: FDA collects samples and analyzes food samples and animal feeds for illegal pes<cide residues. 2

Organic Alterna<ves Organic foods Organic Seals Concerns regarding natural fer<lizer Manure can contribute to contamina<on of crops, soil, or water à pollu<on Can use approved synthe<c and natural

However, drug residues may enter human food à or illness in humans Pollutants Animal manure, factories wastes/dioxins, human sewage can contaminate food produc<on areas Dioxins: chemical compounds

3 Organic Alterna<ves Organic foods Organic Seals Concerns regarding natural fer<lizer Manure can contribute to contamina<on of crops, soil, or water à pollu<on Can use approved synthe<c and natural pes<cides to control weeds and insects Microbial contaminants s<ll found Animal drugs 1. An<bio<cs to maintain animal well- being, but overuse can develop microorganisms à illness in humans 2. However, drug residues may enter human food à or illness in humans Pollutants Animal manure, factories wastes/dioxins, human sewage can contaminate food produc<on areas Dioxins: chemical compounds created in the manufacture, combus<on, and chlorine bleaching of pulp and paper and in other industrial processes. They can accumulate in the food chain and are potent animal carcinogens. : Harmful Toxins Natural Toxins Aflatoxins: Carcinogenic and toxic factors produced by. Ciguatera: A toxin found in tropical. Cooking does not destroy these toxins. Methyl mercury: Results from chemical transforma<on of mercury by. Poisonous mushrooms: cause stomach upset, hallucina<ons, neurological symptoms. Solanine: Toxic substance in improperly stored raw. 3

Figure 14.5 Toxins in the food chain As toxins travel up the food chain, they become concentrated in larger fish. Figure 14.

many government agencies provide oversight. Keeping Food Safe: Government Agencies (Pg587-588) 1.

USDA FSIS: enforces laws governing safety of domes<c and imported product. 4.

4 Figure 14.5 Toxins in the food chain As toxins travel up the food chain, they become concentrated in larger fish. Figure 14.7 Government agencies that help protect our food supply Although the FDA has primary responsibility for the safety of much of our food supply, many government agencies provide oversight. Keeping Food Safe: Government Agencies (Pg ) 1. FDA: enforces laws governing safety of food, except meat and poultry. 2. CDC: monitors/inves<gates outbreaks of and determines proper preven<on 3. USDA FSIS: enforces laws governing safety of domes<c and imported product. 4. USDA CSREES: develops research and educa<on programs on for farmers/consumers 5. EPA: regulates public, approves and other chemicals used in the environment. Keeping Food Safe: Consumer Keep hot foods hot and cold foods cold 1. Clean 2. Separate 3. Cook 4. Chill (refrigerate promptly) 4

Long-term steroid use 5. Liver disease 6. Hemochromatosis 7. Stomach problems Food preserva<on Preserva<ves 1.

5 Risk for Foodborne Illness : Separate, don t cross- contaminate! Separate the re- usable tote bags Use different cuhng boards for vegetables and meat. 1. Immune disorders 2. Cancer 3. Diabetes 4. Long-term steroid use 5. Liver disease 6. Hemochromatosis 7. Stomach problems Food preserva<on Preserva<ves 1. Salt, sugar Most common an<microbial agents 2. An<oxidants prevents changes in color/flavor caused by air exposure Other preserva<on techniques 1. Sal<ng 2. Fermen<ng 3. Drying 4. Canning 5. Hea<ng (e.g. pasteuriza<on) 6. Irradia<on controversial 5

: Irradia<on Irradia<on food is exposed to measured doses of radia<on to reduce or

Bacteriophage: viruses that infect bacteria Bacteriophage Sprayed on ready- to- eat meats

6 : Irradia<on Irradia<on food is exposed to measured doses of radia<on to reduce or eliminate pathogens and kill insects, reduce spoilage, and in certain fruits/vegetables, inhibit sprou<ng and delay ripening. Why are food manufacturers reluctant to use this method of preserva<on? Bacteriophage: viruses that infect bacteria Bacteriophage Sprayed on ready- to- eat meats and poultry products to protect people from bacterial infec<ons Infect only bacteria and do not bother mammalian or plant cells Must declare bacteriophage prepara<on 6

Gene<cally Modified Foods GM foods: Pros and Cons Tradi<onal Breeding Gene<c Engineering Benefits Risks Cross two plants and develop hybrids Takes <me Transform specific genes Less <me needed to get

7 Gene<cally Modified Foods GM foods: Pros and Cons Tradi<onal Breeding Gene<c Engineering Benefits Risks Cross two plants and develop hybrids Takes <me Transform specific genes Less <me needed to get desired effects 1. Enhanced plant growth 2. pes<cide and fer<lizer use 3. Enhanced composi<on 4. Enhanced Poten<al for new Herbicide- resistant weeds Loss of Biggest con of unmonitored GM crops Gene<cally Modified Foods There is no scien<fic evidence that gene<c engineering and irradia<on of foods present unacceptable risks Regula<on oversees gene<cally modified foods Label requirements if food is significantly different Examples: Changes in proper<es Presence of that consumers would not expect in the food Any property that would require special handling, storage, cooking, or preserva<ons. 7

Food Safety. Chapter 13 Food Safety and Technology: Microbial Threats and Gene8c Engineering. Food Safety. Foodborne Illness Outbreaks

Food Safety. Chapter 13 Food Safety and Technology: Microbial Threats and Gene8c Engineering. Food Safety. Foodborne Illness Outbreaks Food Safety Chapter 13 Food Safety and Technology: Microbial Threats and Gene8c Engineering BIOL 103, Spring 2016 Harmful substances in foods Pathogens Bacteria, viruses, parasites Foodborne illness Infec8on