Food Safety

1: Potentially Hazardous Foods As we will discuss further in class, "potentially hazardous food" under most cases must be stored below 41 degrees F. or above 140 degrees F. These foods have the highest potential for spreading foodborne illness. Its fundamental legal definition is: food that can support rapid and progressive growth of microorganisms that may cause food infections or food intoxications. A legal exception to this definition is Clostridium botulinum. Because of the extreme toxicity of its toxins, rapid and progressive growth is not necessary for botulism. Any growth or toxin production of this organism represents a significant risk. Because of the significance of potentially hazardous food, the following conditions (defined by law) allow us to determine foods that are not potentially hazardous: -- pH of 4.6 or less, -- Aw (water activity) of 0.85 or less, -- canned (in hermetically sealed and commercially sterilized containers), or -- exempted by appropriate microbial challenge studies. Try the links to the California Health and Safety Code (click first on "food sanitation" given just below, and then select "CURFFL"), and look at the additional distinctions provided under the law. It is one of the most important definitions you will ever work with in the field. 2. Selected Food-borne Illnesses A. Infections 1. Salmonellosis 2. 3. 4. 5. 6. 7. Campylobacter Listeriosis Hepatitis Brucellosis Trichuriasis Anisakiasis B. Intoxications Salmonella typhimurium Salmonella enteritidis Campylobacter jejuni Listeria monocytogenes type A = infectious Undulant Fever Trichuris thrichiura Anasakidae family (primarily exotoxins) 8. Staphyloccoccus 9. Botulism 10. Perfringens Staphyloccoccus aureus Clostridium botulinum Clostridium perfringens C. Poisonous plants/animals 11. Favism 12. Snake root 13. Paralytic shellfish poisoning 14. Ciguatera 15. Scombroid Vicia faba Eupatorium Scombridae family D. Others 16. agent: reservoir: transmission: symptoms: Vibrio parahemolyticus oceans (variety of seafood) poorly cooked seafood diarrhea, abdominal cramps (rarely fatal) 17. agent: reservoir: transmission: symptoms: Bacillus cereus soil especially cooked rice at room temperatures sometimes vomiting, sometimes diarrhea 18. agent: reservoir: transmission: Clostridium perfringens (anaerobic sporeformer) soil; also, GI tract of healthy humans or animals spores survive normal cooking, then germinate, multiply, and produce toxins diarrhea, nausea; usually no vomiting or fever symptoms: 19. agent: transmission: Copper poisoning copper in prolonged contact with acid foods or carbonated beverages (e.g., improper vending machines) vomiting and weakness in < 1 hour (often minutes) symptoms: 3. Food Controls A. Pasteurization: 1. Ultra Pasteurization: >280 deg. F for >2 seconds 2. Ultra High Temperature: 191-212 deg. F. for 1 to .01 seconds (UHT) 3. High Temp. Short Time: (HTST) 161 deg. F for 15 seconds 4. Holder pasteurizer: 145 deg. F for 30 minutes B. Food and Temperatures: 5. Thermometers: required in refrigerators. should be: 6. Stem (or probe) readily visible at the warmest part of the unit accurate to 1 degree Centigrade designed to check food temperatures typically has metal stem thermometer: with temperature readings at top of thermometer Restaurant operators must have on the premises. 7. Maximum registering thermometer: used to check temperatures in dishwashing machines 8. Refreezing: frozen foods may not be thawed and refrozen (exception: when food is cooked or processed after thawing). C. Canning operations: 1. soaking and washing: reduces spoilage bacteria 2. sorting and grading: consistent quality of product 3. blanching: direct contact with hot water or steam destroys enzymes (reducing chemical changes) softens tissues to fit in can washes away "raw" flavor 4. exhausting: heat foods in cans prior to closing can produces partial vacuum 5. sealing: secures lid on can hermetic double seam when can cools, lids pull in (concave) 6. retort processing: closed vessel for "sterilization" of food 240 degrees for 30 minutes 7. cooling: quick cooling minimizes thermophilic bacteria potential for water contamination through seams (water must be disinfected) D. Dishwashing: 8. Manual method: 3 compartment sink: detergent and warm water: good at removing, not killing bacteria most important step in dishwasing rinse: removes detergent before sanitizer sanitizer: a "polishing" step hot water (180 deg F, 30 seconds) chemicals and warm water (75 deg F): chlorine: 100 ppm for 30 seconds quaternary ammonia: 200 ppm for 1 minute iodine: 25 ppm for 1 minute 9. Machine method: wash: see NSF standards (National Sanitation Foundation) 140-160 deg. F rinse: 180 deg F, 10 seconds, 15-25 psi (water pressure) or chlorine rinse (50 ppm) 4. HACCP = Hazard Analysis and Critical Control Point developed by Pillsbury Company for NASA astronauts in 1960s since then, adopted by FDA, USDA, and Dept. of Commerce predicts hazards and controls them before they happen 1. Identify hazards (i.e., biological, chemical, and physical hazards) identify potentially hazardous foods assess risk (e.g., high, medium, low, negligible) 2. Identify critical control points def. = any point in an operation where the hazard can be eliminated, prevented, or minimized observe the handling of food throughout its lifetime identify: sources of contamination, and potential for microbes to survive or grow 3. Establish controls identify: control criteria (e.g., temperatures) corrective action 4. Monitor monitor the critical control points record the data 5. Establish corrective action take action when criteria are not met 6. Verify that HACCP is functioning 5. Food Safety: Who does what in the federal government? A. hopelessly fragmented: 35 laws 12 agencies 51 interagency agreements (not counting federal-state interagency agreements) B. 6 major agencies: 1. Food and Drug Administration (FDA) 2. Environmental Protection Agency (EPA) 3. National Marine Fisheries Service (NMFS) U.S. Department of Agriculture (USDA): 4. Food Safety and Inspection Service (FSIS) C. funds: 5. Agricultural Marketing Service (AMS) 6. Federal Grain Inspection Service (FGIS) USDA receives about 3/4 of federal funds FDA is second, with about 1/8 of federal funds D. FDA major laws: 1. Food Drug and Cosmetic Act 2. Egg Products Inspection Act 3. Federal Anti-tampering Act 4. Import Milk Act 5. Infant Formula Act 6. Pesticides Monitoring Improvements Act 7. Public Health Service Act 6. Selected Food Additives 1. DES: Diethylstilbestrol synthetic estrogen used to fatten cattle and chickens effects: carcinogen, mutagen FDA banned in 1977 2. sodium nitrite: illegal to mask food interferes with browning of meat: myoglobin + sodium nitrite --> met-myoglobin deters spoilage and botulism in cured meats effects: headaches or hives in sensitive persons nitrites --> nitrosamines (carcinogen) however: not a direct additive no evidence of increased cancer nitrates reduce to nitrites inadult saliva (nitrates found in spinach, celery, lettuce, etc.) 3. monosodium glutamate: (MSG, flavor enhancer, natural flavoring, hydrolyzed vegetable protein) effects: 4. aspartame: headaches, nausea, diarrhea, burning sensation, chest pain, etc. brain lesions in monkeys and mice only in sensitive persons (phenylketonurics) effects: swelling of eyelids, lips, hands, or feet 5. sulfites: effects: abdominal cramps, diarrhea, low blood pressure, elevated pulse, light headedness, chest tightness, asthma, hives FDA banned use on raw fruits and vegetables FDA requires labels when more than 10 ppm