Understanding Microorganisms: Roles, Risks, and Benefits

1. Microorganisms C 5.01 -- Microbiology

2. Microbiology • Microorganisms are everywhere. • Microbiology is the study of microorganisms—living organisms too small to be seen by the naked eye without magnification. C 5.01 -- Microbiology

3. Three Roles of Microorganisms • Pathogens -- cause foodborne illness. • Spoilers -- cause food to spoil and decrease its shelf-life. • Beneficial -- used for food fermentation and are naturally present in and on the body. C 5.01 -- Microbiology

4. Contaminated Food • Microorganisms can contaminate any food: • naturally or • through improper food handling • Contaminated food can cause foodborne illness or food spoilage. • Measures must be implemented to control for: • Food safety – preventing foodborne illness and • Food quality – maximizing shelf-life C 5.01 -- Microbiology

5. Pathogens Foodborne illness • An illness caused by eating contaminated foods or beverages.  Foodborne illness outbreak • the occurrence of two or more cases of a similar illness resulting from eating a common food. Each year there are: • 76 million cases of foodborne illness • 323,914 hospitalizations • 5,194 deaths C 5.01 -- Microbiology

6. Spoilers • Cause the deterioration of food, such as sour milk or lunch meat turning slimy. • Eating spoiled food does not usually cause illness. • Food spoils because of microbial growth or enzymatic activity. C 5.01 -- Microbiology

7. Beneficial • Beneficial microorganisms are not contaminants – they are naturally present or are intentionally added to foods. • Primary purposes: • Health benefits – naturally present on skin and in the intestinal tract. • New food products – use for food fermentation to create new products. Yogurt Sour dough culture C 5.01 -- Microbiology

8. Five Major Groups of Microorganisms • Bacteria • Viruses • Parasites • Mold • Yeast C 5.01 -- Microbiology

9. Bacteria Basics • Invisible to the naked eye. • Pathogens, spoilers, and beneficial. • Grow in food. • Some produce spores. • Some produce toxins. • Not necessarily destroyed by freezing or cooking. Bacillus cereus C 5.01 -- Microbiology

10. Virus Basics • Invisible to the naked eye. • Pathogens -- not spoilers or beneficial. • Do not grow in food; use food as a vehicle to get from one person to another • Can contaminate any food • Cause most foodborne illnesses in the U.S. • Usually destroyed by cooking but not freezing. Norovirus C 5.01 -- Microbiology

11. Parasite Basics • Some are visible to the naked eye • Pathogens – not spoilers or beneficial. • Do not grow in food • Found naturally in many animals • pigs • cats • rodents, and • Seafood • Destroyed by proper freezing and cooking. Anisakis simplex C 5.01 -- Microbiology

12. Mold Basics • Visible to the naked eye. • While most spoil food, some are pathogenic and some beneficial. • Some form toxins that can cause illness. • Grow in a wide range of foods – high acid, low moisture. • Requires air to grow • Freezing does not destroy. C 5.01 -- Microbiology

13. Yeast Basics • Visible to the naked eye. • Spoilers and beneficial but not pathogenic. • Grow in a wide range of foods – high acid, low moisture. • Produce a smell, bubbling, or a taste of alcohol when food spoils • Easily destroyed by proper processing. C 5.01 -- Microbiology