Disease-Causing Microorganisms and the Conditions They Need to Grow Barriers for Controlling the Growth of Microorganisms

Microorganism Small living organism Pathogen A disease-causing microorganism Toxin Poison Spoilage Microorganism Microorganism that causes spoilage, but not illness

Bacteria Viruses Parasites Fungi Microorganisms That Can Contaminate Food and Cause Foodborne Illness

Living, single-celled Carried by food, water, humans and insects Can reproduce rapidly Some survive freezing Some form spores Some spoil food; others cause disease Some cause illness by producing toxins

Growth Stages of Bacteria

Bacterial Growth

What Microorganisms Need to Grow

Food Microorganisms require nutrients to grow Proteins Carbohydrates

Acidity Pathogenic bacteria grow well at a pH of 4.6 to 7.5 Raw Chicken 5.5–6.4 Egg Yolks 6.0–6.3 Butter 6.0–6.8

Temperature The Temperature Danger Zone (TDZ) = 41ºF to 140ºF (5ºC to 60ºC) Most microorganisms grow well in the TDZ Some survive and grow outside the TDZ

Time Pathogenic microorganisms can grow to high levels if they remain in the TDZ for more than four hours

Oxygen Microorganisms have different oxygen needs for growth Aerobic needs oxygen to grow Anaerobic grows only when oxygen is absent Facultative can grow with or without oxygen

Moisture Most potentially hazardous foods have a water activity of.85 or above Raw Chicken and Butter Water Activities of.95–1.0

Barriers That Control the Growth of Microorganisms Make the food more acidic Raise or lower the temperature of the food Lower the water activity Lessen the time in the TDZ

Salmonellosis Shigellosis Listeriosis Staphyloccocal food poisoning Clostridium perfringens Enteritis Major Foodborne Illnesses Caused by Bacteria Bacillus cereus gastroenteritis Botulism Campylobacteriosis E. coli O157:H7 EHEC Vibrio gastroenteritis Yersiniosis

Salmonellosis Type of Illness: Infection, possibly toxin-mediated

Listeriosis Type of Illness: Infection

Staphylococcal Food Poisoning Type of Illness: Intoxication

Clostridium perfringens Type of Illness: Toxin-mediated infection

Botulism Type of Illness: Intoxication

E. coli O157:H7 EHEC Type of Illness: Toxin-mediated infection

Can’t reproduce outside a living cell Do not require a PHF to be transmitted Usually contaminate food through poor personal hygiene May survive freezing and cooking Contaminate food and water

Hepatitis A Norwalk Virus Gastroenteritis Rotavirus Gastroenteritis Major Foodborne Illnesses Caused by Viruses

Hepatitis A Type of Illness: Infection

Norwalk Virus Gastroenteritis Type of Illness: Infection

Parasites Need to live in or on a host organism in order to survive Host Person Animal Plant

Freeze properly Cook to proper temperatures Avoid cross-contamination Use sanitary water supplies Wash hands properly Keys to Prevention

Trichinosis Anisakiasis Giardiasis Toxoplasmosis Intestinal Cryptosporidiosis Cyclosporiasis Major Foodborne Illnesses Caused by Parasites

Trichinosis Type of Illness: Infection

Anisakiasis Type of Illness: Infection

Fungi Molds Yeasts Mushrooms Fungi Commonly cause food spoilage, not illness

Foodborne Infections Result when pathogens grow in intestines after a person eats food contaminated by them Foodborne Intoxications Result from eating food containing poisonous toxins Foodborne Toxin-Mediated Infections Result from toxins produced by pathogens growing in the intestines

Prepare an outline for a discussion of the four types of microorganisms. Include examples of what microorganisms need to survive and grow. Highlight the conditions managers have the most influence over.

Challenge participants to create a list of foods high in acid and another list of highly alkaline foods. Reward the participant who comes up with the most examples and have him or her share the list with the class. Create a blank handout of a thermometer and have participants indicate the space for the temperature danger zone.