1. Introducing: FAT TOM Guidelines on how to keep food safe: F = Food T = Time A = Acidity O = Oxygen T = Temperature M = Moisture

2. APPETIZER ?’s On your guided notes, brainstorm and answer the following: 0 How do you think food becomes dangerous? 0 What conditions can create a hazardous environment? Be prepared to share your ideas. 2

3. LEARNING GOALS  Students will be able to: 1. Define the terms related to the growth of microorganisms 2. Identify the methods of growth of microorganisms 3. Explain the relationship between the growth of microorganisms and food items PROPERTY OF PIMA COUNTY JTED 2009 3

4. 4 FAT TOM F.A.T.T.O.M. explains what allows foodborne pathogens to grow. FAT TOM will help you to remember these valuable terms: Food Acidity Time Temperature Oxygen Moisture

5. PROPERTY OF PIMA COUNTY JTED 2009 5 FAT TOM: F= FOOD Microsoft Gallery

6. 6 FOOD The nutrients available in food often determines whether microorganisms will grow. While some microorganisms have simple nutrient requirements, some pathogens require a complex diet, including proteins. Moist protein-rich foods, such as meat, milk, eggs and fish, are potentially hazardous. They are most likely to cause foodborne illness because they are a food source for pathogenic bacteria and can support growth of these bacteria.

7. 7 ACIDITY The degree of acidity or alkalinity (base) of a substance is measured by its pH. pH is measured on a scale from 0 to 14.0. An environment with a pH of 7.0 is exactly neutral. Foods with a pH below 7.0 are acidic; a pH above 7.0 is alkaline. The lower the pH, the higher the acidity; the higher the pH, the lower the acidity. Bacteria grow best in an environment that is neutral or slightly acidic. Most bacterial growth is inhibited in very acidic conditions. That is why acidic foods, like vinegar and fresh fruits (especially citrus), seldom provide a favorable climate for pathogenic bacteria. Most bacteria will not grow at pH levels below 4.6 because the environment is too acidic. Microorganisms thrive in a pH range between 6.6 and 7.5.

8. 8 FAT TOM: A= ACIDITY ALKALINE ACIDIC NEUTRAL The problem foods are in the middle (pH = 4.6 – 7.5) neither an acid nor a base. Protein foods are problem foods. http://www.flickr.com/photos/katerha/4671551534/ Microsoft Gallery

9. PROPERTY OF PIMA COUNTY JTED 2009 9 FAT TOM: T= TEMPERATURE 32º Freezing 212º Boiling Danger zone: 41º - 135º

10. 10 T= TEMPERATURE Microorganisms grow and reproduce quickly between the temperatures of 41° and 135°F (5° to 57° c). During the two-hour period in the TEMPERATURE DANGER ZONE (TDZ), minimal growth and reproduction will occur especially if there is a neutral environment and protein source. One important rule of food safety is to limit time that foods are in the TDZ. Keep foods refrigerated (below 41°F) until it is time to cook. Cool left over foods quickly.

11. 11 TIME Also known as the four-hour rule Pathogenic microorganisms reproduce by cell division. One becomes two. Two become four. Small numbers of pathogens may be present in foods, but they pose a very low risk to consumers, especially if the food is cooked. However, when low acid and high protein available foods (neutral or alkaline pH) are abused by placing them in the TEMPERATURE DANGER ZONE (TDZ) (41° to 135°F) for more than four hours, pathogens will have multiplied to such high levels in the food, eating this food will make people ill rapidly. Restricting the time low acid and high protein foods stay in the TDZ to two hours or less prevents growth of large numbers of pathogens.

12. PROPERTY OF PIMA COUNTY JTED 2009 12 FAT TOM: T= TIME Danger zone: four illness After four hours, microorganisms will have grown to a high enough level to cause illness.

13. PROPERTY OF PIMA COUNTY JTED 2009 13 FAT TOM: O= OXYGEN OXYGEN Some microorganisms need OXYGEN to grow. Others do not.

14. 14 OXYGEN Microorganisms that need oxygen (air) to grow are called aerobic. When foods such as meat, spaghetti sauce or vegetables are canned, oxygen is excluded from the environment. Therefore, growth of aerobic organisms is controlled and the food is preserved. Such foods are shelf stable and do not require refrigeration until they are opened. Some microorganisms will grow only in anaerobic conditions (in the absence of oxygen). Botulism, a rare type of foodborne illness, is caused by a specific type of bacteria called clostridium botulism that grows only in anaerobic conditions. Improperly preserved home canned foods are a typical source of botulism. Home canned items can not be used in foodservices.

15. PROPERTY OF PIMA COUNTY JTED 2009 15 FAT TOM: M= MOISTURE MOISTURE Microorganisms need MOISTURE to grow. Microsoft Gallery

16. 16 Moisture content Microorganisms Microorganisms must have an abundant supply of water to grow. Food perishability Food perishability is related to moisture content and water activity level. Moisture content ( a w ) 0 to 1.0. Moisture content is the amount of water in food expressed as a percentage. Water activity ( a w ) is the amount of water available for use and is measured on a scale of 0 to 1.0.

17. 17 Moisture content Bacteria, yeast, and molds multiply rapidly with a high water activity level. a w ( a w > 0.86) a w a w Meat, produce and soft cheeses are examples of foods with a w in this range (a w = 0.86 to 1.0). http://www.flickr.com/photos/dongkwan/2215655020/Microsoft Gallery http://www.flickr.com/photos/digitalcolony/2689103249/

18. 18 MOISTURE Foods preserved with salt or sugar, such as beef jerky or jams and jellies have a lower aw because salt and sugar deprive microorganisms of water and inhibit their reproduction. These products are shelf-stable (i.e. they do not need refrigeration, unless opened). Pathogenic bacteria have difficulty growing in foods such as dry noodles, flours, candies and crackers, where aw is below 0.85.

19. PROPERTY OF PIMA COUNTY JTED 2009 19 AVOIDING PROBLEMS FAT TOM: AVOIDING PROBLEMS  Practice safe & sanitary food handling  Use ice baths or ice paddles to cool food (never put hot food directly into the refrigerator)  Shallow metal pans cool food down quickly  Maintain food at safe temperatures, including during transportation

20. 20 ARTICLE FACTS Read the Article: “Are Sprouts Safe to Eat?” by Jackie Newgent, registered dietitian nutritionist Locate 5 vocabulary words you do not know and write them down Why did I ask you to read this article? What do sprouts and FAT TOM have in common?

21. 21 Let’s APPLY What We Learned! Time For a Quick Quiz Answer the questions on your guided note sheet and see what you remember from the lesson

22. 22 Closure At the bottom of your FAT TOM guided notes, Answer one of the following in one minute: main idea or concept In one or two sentences summarize the main idea or concept of this lesson. questions Write any unanswered questions you may have. real-world applications Describe the real-world applications of this lesson