FOOD SAFETY. By Lily Ou Emily Hu Theodore Lin

Transcription

1 FOOD SAFETY By Lily Ou Emily Hu Theodore Lin

2 FOODBORNE ILLNESS Noninfectious agents: nonbacterial toxins, chemical residues, pesticides, antibiotics, physical hazards etc. What? A disease caused by ingesting unsafe food. Also known as food poisoning. Infectious Agents: also known as pathogens: bacteria, viruses, molds, fungi, parasites etc. Not all microbes make you sick or are harmful. Serotypes: a specific strain of a larger class of organism. Process of getting sick: Incubation period: the time between when infection occurs and signs and symptoms begin.

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5 TOXINS MADE BEFORE INGESTION Performed Toxins: poisonous substances produced by microbes while they are in food (prior to ingestion). Staphlococcus Aureus - occurs in undercooked meat and unpasteurized dairy products. -Symptoms: nausea and vomiting, diarrhea, abdominal cramps after 1-6 of food consumption. - Heat stable so it isn t easily killed through cooking. Methicillin-resistant Staphylococcus Aureus: - Resistant to most antibiotics. - Transmitted through sharing towels and equipment in athletic and school facilities. - Prevention: proper hand washing.

6 Aspergillus Clostridium Botulinum - Found in inadequately processed, low-acid, homecanned foods (eg. Green beans), and canned commercial foods - Can be destroyed at high temperatures - Causes botulism: vomiting and diarrhea, double or blurred vision, drooping eyelids, slurred speech, difficulty swallowing, dry mouth, muscle weakness. Sometimes paralysis, respiratory failure and death. - Molds that grow on foods. - Eg. Aflatoxin: found on agricultural crops like peanuts. If it is not dried properly, it can grow and produce toxic levels of aflatoxin. - Fatal - Causes liver damage and cancer.

7 TOXINS MADE AFTER INGESTION Enteric or Intestinal toxins: toxins produced by an organism after it enters the GI tract. Noroviruses: an infectious pathogen. Enterotoxigenic: produces enteric toxins and can severely upset the GI tract. Symptons: 6-48 hours, diarrhea, cramps, nausea. Foods: uncooked vegetables, fuits, raw meats and seafoods, unpasteurized dairy, untreated tap water.

8 ORGANISMS THAT INVADE INTESTINAL CELLS Enterohemorrhagic: pathogens that cause bloody diarrhea Salmonella: - Found in raw poultry, beef, dirty fruit, alfalfa sprouts. - Incubation period: 1-3 days - Severe GI upset and headaches E. Coli 0157:H7: - Found in unpasteurized milk, apple juice, apple cider, improperly prepared meat. - Incubation period: 1-8 days - Nausea, cramps, severe diarrhea.

9 PARASITES: PROTOZOA AND WORMS Parasites: complex one-celled or multicellular organisms that rely on other organisms to survive and are dangerous. Protozoa: one-celled organism which can live inside the intestinal tracts of both animals and humans. Form cysts that are excreted in the feces, you can get them if you consume foods with the cysts - eg. Giardia intestinalis: found in untreated swimming pools and hot tubs. (this is why there is chlorine in pools) Worms: also form cysts; can travel through blood and go into many locations like the muscles, eyes, and the brain. Eg. Anisakis Simples: roundworm - Violent abdominal pain, nausea, vomiting. - Found in raw fish (sushi and sashimi) - Freezing can kill it.

10 PRIONS A misshapen protein that causes other proteins to also become distorted which damages nervous tissue. They re hard to destroy and can be transmitted. Creutzfeldt-Jakob disease: fatal disease in humans caused by genetic mutation or surgical contamination (with prions). Mad Cow Disease: - Also known as Bovine Spongiform Encephalitis. - Symptoms: loss of motor control, confusion, paralysis, wasting, and death. Policy: World Health Organization (WHO) recommends that all governments prohibit the feeding of highly innervated tissue (brain and spinal cord) from animals.

11 HOW CAN NONINFECTIOUS SUBSTANCES CAUSE FOODBORNE ILLNESS? Nonliving compounds that can still make you sick Physical Contaminants (glass and plastic), Toxins, heavy metals, and pesticides

12 ALGAE TOXINS Shellfish Poisoning: a group of foodborne illnesses caused by consuming shellfish that contain marine toxins Due to the fact that these marine animals consume large amounts of algae that sometimes produce marine toxins Marine Toxins: a poison produced by ocean algae Neurologic symptoms tingling, burning, numbness, drowsiness, and difficulty breathing Hot-Cold Inversion cold is perceived as hot and hot is perceived as cold

13 RED TIDE Phenomenon in which certain ocean algae grow profusely, causing reddish discoloration of the water During this period of rapid growth, algae produces brevetoxins Brevetoxin toxin produced by red tide, causing algae, which, when consumed, cause shellfish poisoning

14 PESTICIDES, HERBICIDES, ANTIBIOTICS, AND HORMONES Many federal and international agencies work together to assure that food is free of any kind of pesticides, herbicides, antibiotics, and hormones that may pose a threat to the consumer and the environment Food and Agriculture Organization of the United Nations U.S. Environmental Protection Agency FDA U.S. Department of Agriculture

15 EXAMPLES OF DANGEROUS PESTICIDE AND HORMONE 1. Pesticide Dicholoro-diphenyl-trichloroethane (DDT) pesticide once used to kill mosquitoes and increase crop yields a damage to wildlife banned in Hormone Bovine Somatotropin (bst) protein hormone produced by cattle and used in the dairy industry to enhance milk production It is generally safe for both cow and the consumer, however there are no laws requiring milk produced by cows treated with bst to be labeled skeptical of its safety

16 FOOD ALLERGIES Because the percentage of individuals who have an adverse reaction to these compounds is small, the compounds are not prohibited. EX: Some people are particularly sensitive to monosodium glutamate (MSG), which is used as a flavor enhancer. Sulfites a naturally occurring compound, in some foods, that can be used as a food additive to prevent discoloration and bacterial growth Used in wine and dried fruits Causes breathing difficulties in sulfite-sensitive people FDA: labelling all foods containing at least 10 part per million sulfites

17 NEW FOOD SAFETY CONCERNS 1. Acrylamide - A compound that is formed in starchy foods when heated to high temperatures - Used to make polyacrylamide found in some food packaging materials - High levels of it cause cancer in laboratory animals 2. Melamine - A nitrogen-containing chemical used to make lightweight plastic objects - Melamine is rich in nitrogen Chinese gluten manufacturers added it to their products to make them appear higher in protein than they actually are - Low risk to human health if people consume meat and milk from animals fed melamine-tainted feed HOWEVER proven incorrect in 2008 when melamine-contaminated milk entered Chinese markets

18 NEW FOOD SAFETY CONCERNS 1. Lead and Bisphenol A - Consuming is dangerous denatures proteins and can lead to serious neurological complications - Children playing with toys with lead-containing paints eating it through physical contact with food - Bisphenol A (BPA) a chemical used in the production of many plastic items including baby bottles - BPA may influence long-term risk for cancer and reproductive abnormalities in la animals - Choosing glass or metal containers over polycarbonate ones, not put plastics in the microwave, and wash plastic containers by hand instead of in the dishwasher

19 HOW DO FOOD MANUFACTURERS PREVENT CONTAMINATION? - Cross-Contamination transfer of microorganisms from one food to another or from one surface or utensil to another

20 CAREFUL FOOD-HANDLING TECHNIQUES - Pathogens can be easily transmitted to almost any food by an infected person - Food handlers avoid contaminating the food by coughing or sneezing on foods - Fecal contamination of foods (because pathogens can pass through GI tract and be excreted in the feces) - People who process and prepare food are generally required to wear gloves and thoroughly wash their hands

21 PROPER FOOD PRODUCTION, PRESERVATION, AND PACKAGING - Goal: produce a product that is as pathogen-free as possible and then to store it in a way that does not allow pathogenic growth - Hazard Analysis Critical Control Points (HACCP) System USDA food safety protocol used to decrease contamination of foods during processing - Identify the critical points in food-processing where contamination is most likely - USDA: requires meat and poultry be inspected before sale, guidelines for safe handling appear on packages

22 PRESERVING FOOD 1. Drying, salting, and smoking, when done correctly, inhibit bacterial growth preserving meat 2. Fermentation: metabolism, by bacteria, that occurs under relatively anaerobic conditions a. Adding selected microorganisms to food b. Used in making sauerkraut, yogurt, pickles, and wine c. Promotes growth of nonpathogenic organisms minimize the growth of pathogenic organisms 3. Heat Treatment cooking, canning, and pasteurization a. Danger zone temperature range between 40 and 140F in which pathogenic organisms grow most readily b. Packaged or Canned food heated in high temperatures killed pathogens vacuum is created air-free environment helps preserve the food because organisms require oxygen to grow c. Pasteurization a food preservation process that subjects foods to heat to kill bacteria, yeasts, and molds; widely used in milk, juice, spices, ice cream, and cheese

23 PRESERVING FOOD 1. Cold Treatment: Cooling and Freezing a. To slow or halt the growth of microorganisms, always refrigerate foods at 40F or freeze them soon after they are prepared prevent foods from staying in danger zone for a long time 2. Irradiation a. Food preservation process that applies radiant energy to foods to kill bacteria b. Cold pasteurization c. Used for space travel d. Irradiation neither damages nutrients nor makes the food radioactive e. Makes food safer to eat and dramatically increase shelf life 3. Edible Films a. Product made from natural edible substances intended for wrapping and protecting food b. Eco-friendlyfilms protect foods from drying out and also inhibit bacterial growth and increase shelf life

24 WHAT STEPS CAN YOU TAKE TO REDUCE FOODBORNE ILLNESS? Consumer Advisory Bulletins Toll free numbers + USDA, FDA sites to find out important food safety information! Eg: cts/index.asp

25 FIGHTBAC! CAMPAIGN Set of food safety guidelines developed by USDA + Partnership for Food Safety Education 1. Clean Hands, Surface, and Cooking Utensils 2. Wash fruits and vegetables.

26 3. Separate foods to prevent cross-contamination. 4. Cook foods to proper temperature.

27 5. Keep food cold, chill them, and when in doubt, throw out.

28 WHAT ABOUT AVOIDING FOODBORNE ILLNESS WHILE TRAVELING OR CAMPING? Water + fresh produce pose greatest risks outdoors When travelling to foreign countries, be careful what you eat, or you may get diarrhea In case of diarrhea, recover electrolytes + fluids

29 1. Drink only purified water 2. Avoid or carefully wash fresh fruit/vegetables 3. Avoid eating cow in places with Creutzfelt-Jakob Disease

30 WHAT ARE SOME EMERGING ISSUES OF FOOD BIOSECURITY? Food biosecurity prevention of terrorist attacks on the food supply Bioterrorism Act of 2002 Clostridium botulinum could be used by terrorists Origin of all foods clearly labeled