Understanding the Microworld Chapter Number 2 Understanding the Microworld Class Name Instructor Name Date, Semester Book Title Book Author

Learning Objectives After this presentation, you should be able to complete the following Learning Outcomes 2.0 Factors that affect the growth of foodborne pathogens (FAT TOM) 2.1 2.2 Characteristics of TCS food Major foodborne pathogens and their sources 2.3 At the end of this lecture each student should have a general understanding of the chapter contents and a firm ability to accomplish the learning outcomes on this slide. Ways of preventing viral, bacteria, parasitic, and fungal contamination 2.4 2.5 Naturally occurring toxins and how to prevent their illnesses

2.0 KEY TERMS • Microorganisms: Small, living organisms that can be seen only with the aid of a microscope. There are four types of microorganisms that can contaminate food and cause foodborne illness: bacteria, viruses, parasites, and fungi. • Pathogens: Illness-causing microorganisms. • Toxins: Poisons produced by pathogens, plants, or animals. Some occur in animals as a result of their diet.

2.0 KEY TERMS Bacteria: Single-celled, living microorganisms that can spoil food and cause foodborne illness. Bacteria present in food can quickly multiply to dangerous levels when food is incorrectly cooked, held, or reheated. Some form spores that can survive freezing and very high temperatures. FAT TOM: Acronym for the conditions needed by most foodborne microorganisms to grow: food, acidity, temperature, time, oxygen, moisture.

2.0 KEY TERMS • Temperature danger zone: The temperature range between 41° and 135°F (5° to 57°C), within which most foodborne microorganisms rapidly grow. • Water activity (a): Amount of moisture available in food for microorganisms to grow. It is measured in a scale from 0.0 to 1.0, with water having a water activity (aw) of 1.0. TCS food typically has a water-activity value of 0.85 or higher.

2.0 KEY TERMS • Spore: Form that some bacteria can take to protect themselves when nutrients are not available. Spores are commonly found in dirt and can contaminate food grown there. A spore can resist heat, allowing it to survive cooking temperatures. Spores can also revert back to a form capable of growth. This can occur when food is not held at the correct temperature or cooled or reheated correctly. • Virus: Smallest of the microbial food contaminants. Viruses rely on a living host to reproduce. They usually contaminate food through a food handler’s incorrect personal hygiene. Some survive freezing and cooking temperatures.

2.0 KEY TERMS • Spore: Form that some bacteria can take to protect themselves when nutrients are not available. Spores are commonly found in dirt and can contaminate food grown there. A spore can resist heat, allowing it to survive cooking temperatures. Spores can also revert back to a form capable of growth. This can occur when food is not held at the correct temperature or cooled or reheated correctly. • Virus: Smallest of the microbial food contaminants. Viruses rely on a living host to reproduce. They usually contaminate food through a food handler’s incorrect personal hygiene. Some survive freezing and cooking temperatures.

2.0 KEY TERMS • Parasite: Organism that needs to live in a host organism to survive. Parasites can be found in water and inside many animals, such as cows, chickens, pigs, and fish. Correct cooking and freezing will kill parasites. Avoiding cross-contamination and practicing correct handwashing can also prevent illness. • Fungi: Ranging in size from microscopic, single-celled organisms to very large, multicellular organisms, fungi most often cause food to spoil. Molds, yeasts, and mushrooms are examples. • Mold: Type of fungi that causes food spoilage. Some molds produce toxins that can cause foodborne illness. • Yeast: Type of fungi that causes food spoilage.

F A T T O M 2.1 Factors That Affect the Growth of Foodborne Pathogens CIDITY F A T T O M IME EMPERATURE Food Most bacteria need nutrients such as carbohydrates or proteins to survive. TCS food supports the growth of bacteria better than other types of food. This includes meat, poultry, dairy products, and eggs. Acidity Bacteria grow best in food that contains little or no acid. pH is the measure of acidity. The pH scale ranges from 0 to 14.0. A value of 0 is highly acidic, while a value of 14.0 is highly alkaline. A pH of 7.0 is neutral. Bacteria grow best in food that is neutral to slightly acidic, a pH of 7.5 to 4.6. Temperature Bacteria grow rapidly between 41° and 135°F (5° and 57°C), as shown in the illustration at left. This range is known as the temperature danger zone. Bacteria grow even more rapidly from 70° to 125°F (21° to 52°C). Bacterial growth is limited when food is held above or below the temperature danger zone. Time Bacteria need time to grow. The more time bacteria spend in the temperature danger zone, the more opportunity they have to grow to unsafe levels. Oxygen Some bacteria need oxygen to grow. Others grow when oxygen is not there. Bacteria that grow without oxygen can occur in cooked rice, untreated garlic-and-oil mixtures, and temperature-abused baked potatoes. Moisture Bacteria grow well in food with high levels of moisture. The amount of moisture available in food for this growth is called water activity (aw). The aw scale ranges from 0.0 to 1.0. The higher the value, the more available moisture in the food. XYGEN OISTURE

2.1 Factors That Affect the Growth of Foodborne Pathogens FOOD Most bacteria need nutrients such as carbohydrates or proteins to survive. This includes meat, poultry, dairy products, and eggs.

2.1 Factors That Affect the Growth of Foodborne Pathogens ACIDITY Bacteria grow best in food that is neutral to slightly acidic, a pH of 7.5 to 4.6. The following common types of food have a pH that is ideal for bacterial growth: Bread – pH 5.0 – 6.0 Raw Chicken – pH 5.5 – 6.0 Canteloupe – pH 6.1 – 6.5 Milk – pH 6.4 – 6.8

2.1 Factors That Affect the Growth of Foodborne Pathogens TEMPERATURE Bacteria grow rapidly between 41° and 135°F (5° and 57°C) This is called the Temperature Danger Zone. Bacteria grow even more rapidly from 70° to 125°F (21° to 52°C).

Foodborne Illness TIME 2.1 Factors That Affect the Growth of Foodborne Pathogens TIME Bacteria need time to grow. The more time bacteria spend in the temperature danger zone, the more opportunity they have to grow to unsafe levels. Foodborne Illness

2.1 Factors That Affect the Growth of Foodborne Pathogens OXYGEN Some bacteria need oxygen to grow. Others grow when oxygen is not there. Bacteria that grow without oxygen can occur in: Cooked Rice Garlic/Oil Mixes Baked Potatoes

MOISTURE 2.1 Factors That Affect the Growth of Foodborne Pathogens Bacteria grow well in food with high levels of moisture. The amount of moisture available in food for this growth is called water activity (aw). The aw scale ranges from 0.0 to 1.0. The higher the value, the more available moisture in the food.

TCS (Time and Temperature Control for Safety): 2.2 Characteristics of TCS Food TCS (Time and Temperature Control for Safety): TCS food is typically moist and contains protein, as well as having a neutral or slightly acidic pH.

TCS (Time and Temperature Control for Safety): 2.2 Characteristics of TCS Food TCS (Time and Temperature Control for Safety): This food also has a history of involvement in foodborne illness outbreaks, as well as a natural potential for contamination due to methods used to produce/process it.

Major Foodborne Pathogens 2.3 Major Foodborne Pathogens Microorganisms are small, living organisms that can be seen only through a microscope. Many microorganisms are harmless, but some can cause illness. These are called pathogens. Some pathogens make you sick when you eat them. Others produce poisons—or toxins—that make you sick.

Ways Pathogens can be Spread 2.3 Major Foodborne Pathogens Ways Pathogens can be Spread Person to person Touching dirty food-contact surfaces and then touching food Sneezing or vomiting onto food or food-contact surfaces

Major Foodborne Pathogens 2.3 Major Foodborne Pathogens The symptoms of a foodborne illness vary, depending on which illness a person has. But most victims share some common symptoms: Diarrhea Vomiting Fever Nausea Abdominal cramps Jaundice (a yellowing of the skin and eyes)

Major Foodborne Pathogens 2.3 Major Foodborne Pathogens The Big Five Shigella spp Salmonella Typhi Enterohemorrhagic and shiga toxin-producing E. coli Hepatitis A Norovirus

Prevent Contamination Avoid bare-hand contact with ready-to-eat food 2.4 Ways of preventing viral, bacterial, parasitic, and fungal contamination Prohibit food handlers who are vomiting or who have diarrhea or jaundice from working Prevent Contamination Avoid bare-hand contact with ready-to-eat food Make sure food handlers wash their hands regularly and correctly

2.5 Naturally occurring toxins and ways of preventing illnesses from them Seafood Toxins Fish toxins can be a natural part of the fish. Other toxins are made by pathogens on the fish. Some also occur when fish eat smaller fish containing the toxin. Shellfish, such as oysters, can likewise become contaminated when they eat marine algae that have a toxin.

2.5 Naturally occurring toxins and ways of preventing illnesses from them MUSHROOM TOXINS Foodborne illnesses linked with mushrooms are almost always caused by eating toxic wild mushrooms collected by amateur hunters. Purchasing products from approved, reputable suppliers helps prevent these types of foodborne illnesses.

2.5 Naturally occurring toxins and ways of preventing illnesses from them PLANT TOXINS Plant toxins are another form of biological contamination. Illnesses from plant toxins usually happen because an operation has purchased plants from an unapproved source. The following are examples of items that have made people sick: Toxic plants, such as fool’s parsley or wild turnips, mistaken for the edible version Honey from bees allowed to harvest nectar from toxic plants Undercooked kidney beans