1. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Food safety

2. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Why is Food Safety Important? Food-borne illness: symptoms or illness from food or water that contains an infectious agent, poisonous substance, or protein causing an immune reaction. 76 million people report food-borne illness each year. Many more cases go unreported.

3. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Why is Food Safety Important? Food spoilage can be from enzymes naturally found in the food or from microbes that colonize the food. Processed foods can spoil just as fresh meats, fruits, and vegetables do. Three factors most often responsible are: (1) oxygen (2) light (3) heat

4. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Why is Food Safety Important? Food producers may use chemicals, drugs, or other substances to manipulate food products. Food additives: chemicals added to enhance foods. Food preservatives: chemicals added to food to maintain freshness and appearance. Pesticides: family of chemicals used in both the field and storage areas to decrease plant, fungal and animal pests.

5. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Government Regulators Multiple government agencies are involved in ensuring the safety and quality of the food supply: States Department of Agriculture (USDA) U.S. Food and Drug Administration (FDA) Centers for Disease Control and Prevention (CDC) Environmental Protection Agency (EPA)

6. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Causes of Food-Borne Illness Food infections: illness resulting from eating food contaminated with living organisms. Food intoxications: illness resulting from eating food in which microbes have secreted toxins (poisons).

7. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Causes of Food-Borne Illness Bacteria are the most common microbes causing food-borne illnesses. Of the bacteria, the most common food contaminants are: Campylobacter jejuni Salmonella Also, Listeria monocytogenes, Shigella, Vibrio

8. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Causes of Food-Borne Illness Campylobacter jejuni Campylobacteriosis: Diarrhea Cramping Abdominal pain Fever withing 2-5 days post-exposure Commonly found in chickens, also cow’s udders More than ½ of raw chicken in the US market has Campylobacter on it

9. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Salmonella invading cultured human cells Credit Rocky Mountain Laboratories, NIAID, NIH Salmonella Salmonellosis Diarrhea Abdominal cramps Fever 12-72 hours post- infection Infection may last 4-7 days Salmonella live in the intestinal tracts of humans and other animals Foods of animal origin may be contaminated: raw eggs, unpasteurized milk and raw meat, also unwashed produce

10. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Causes of Food-Borne Illness Other microbes causing illness include Viruses such as hepatitis A, hepatitis E, Norwalk virus Helminths or worms, such as tapeworms, flukes, and roundworms. Giardia, causing a diarrheal illness called giardiasis Fungi causing food spoilage

11. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Hepatitis E Drs. E.M. Kraan a, dr. M. Koopmans b, dr. P.M. Schneeberger c, Fataal verlopen infectie met in Nederland verworven hepatitis E virus bij een patiënte met een vermoedelijk hepatocellulair carcinoom

12. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Parasitic worms Brain scan of pork tapeworm Taenia tolium Credit: Red Book Online, American Academy of Pediatrics

13. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Toxoplasma gondii Parasite Modes of transmission: (1)consumption of raw foods (2)Fecal-oral route (3)Mother to fetus (4)Blood transfusion (rare) Credit: Image provided by Ke Hu and John Murray

14. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Giardia Credit: Public Health Image Library Content Providers(s): CDC/ Janice Carr SEM image:

15. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Causes of Food-Borne Illness Some microbes cause illness by secreting poisons called toxins. Clostridium botulinum produces botulism toxin which blocks nerve transmissions to muscle cells. Mycotoxins are secreted by fungi. Toxins can be neurotoxins or enterotoxins.

16. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Food Allergies Allergic reactions to food may include symptoms such as rashes, headaches, or bowel disturbances. The foods that most often cause allergic reactions include cow’s milk, eggs, nuts, citrus fruit, seafood, wheat, corn, soy. Most food allergies are reactions to proteins contained in the food.

17. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Food Allergies Some food allergies are fixed – the reaction occurs every time the food is eaten. Some food allergies are cyclic – after 3 to 6 months without the food, it may be slowly reintroduced to the diet with no effect. Many children outgrow early food allergies.

18. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Preventing Food-Borne Illness When preparing foods at home, be sure to Wash hands and kitchen surfaces often Separate foods to prevent cross contamination Cook foods the their proper temperature Chill foods to prevent microbes from growing

19. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Preventing Food-Borne Illness

20. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Preventing Food-Borne Illness Foods should be cooked thoroughly to kill microbes. Leftovers should be stored in the refrigerator for a limited period of time. Food should be thawed slowly in the refrigerator.

21. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Preventing Food-Borne Illness

22. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Preventing Food-Borne Illness

23. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Preventing Food-Borne Illness

24. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Preventing Food-Borne Illness Thoroughly cooking food destroys microbes but toxins may remain in the food.

25. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Preventing Food-Borne Illness When eating out: Eat at restaurants that look clean Insist that food be cooked thoroughly When traveling: Avoid raw foods, salads, uncooked fruits and vegetables, unpastuerized milk Only drink bottled water or soda, boiled water such as tea, beer, wine

26. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Preventing Food Spoilage Spoilage can be prevented by many natural techniques: Salting or sugaring Drying the food Smoking Cooling

27. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Preventing Food Spoilage More modern techniques include: Industrial canning Pasteurization Chemical preservatives Irradiation Genetic modification

28. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Preventing Food Spoilage

29. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Food Additives Natural food additives include beet juice, salt, and citric acid. Many other additives are synthetic chemicals added to food. Additives can be used for adding flavor, color, or nutrients to foods.

30. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Food Additives Flavorings: Flavoring agents such as essential oils or spices are used to replace flavor lost during processing. Flavor enhancers do not have flavor of their own. Examples include maltol and MSG

31. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Food Additives Colorings: Beet juice (red), beta carotene (yellow), and caramel (brown) are natural coloring agents Vitamins and minerals: Vitamin E, ascorbic acid (vitamin C), vitamin D, iodine

32. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Food Additives Other food additives include: Texturizers, stabilizers, thickening agents, or emulsifiers that change the consistency of processed foods Humectants or desiccants that maintain the proper moisture levels Bleaching agents to change the color of food

33. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Residues on Foods Various chemicals can persist and even accumulate in foods. These residues can include: Persistent organic pollutants (POPs) Pesticides Growth hormones

34. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Persistent Organic Pollutants Persistent organic pollutants: chemicals released into the atmosphere from industry, agriculture, automobiles, and waste disposal. Found on virtually all categories of food. Includes: Mercury and lead PCBs dioxins

35. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Pesticides Pesticides are used to help protect against crop losses, reduce the incidence of disease, and increase crop yields. Most common are insecticides, herbicides, fungicides Can be natural or synthetic Can remain as a toxin on foods Regulated by the EPA

36. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Growth Hormones Recombinant bovine growth hormone (rBGH) is a genetically engineered growth hormone given to cows Increases muscle mass; decreases fat Increases milk production Causes mastitis in cows, resulting in increased antibiotic use in the cows Risks to humans are still being studied

37. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Organic Foods Organic foods are grown without the use of synthetic pesticides Standards for organic production are regulated by the USDA Benefits of organic foods: 2.5 times more nutritious Higher vitamin and mineral content Lower in toxic metals