This document discusses various microorganisms that can contaminate food and cause foodborne illness. It defines microorganisms, pathogens, and germs. The main types discussed are bacteria including Salmonella, Listeria, Staphylococcus, Botulism, and E. coli. Viruses like Hepatitis A and Norovirus are also mentioned. Parasites such as those that cause Anisakiasis are noted. Finally, the document briefly covers fungi including molds, yeasts, and aflatoxins produced by molds.

2. Introduction
 Microorganisms are small, living
organisms that can only be seen by
microscope.
 Pathogens are microorganisms that
cause illness.
 The consumption of food with toxins
(poisons) is the leading cause of
foodborne illness.

3.  What are Germs?
Germs are microorganisms that are likely to cause
disease
Microorganisms are found throughout the
environment. Only
a very small number are pathogenic, i.e. capable
of causing disease, and not all diseases are
caused by microorganisms
Some bacteria live in our gut and help to digest
food.Some yeasts and bacteria are used in baking,
brewing
or cheese making
Bacteria are just one type of micro-organism,
alongside viruses, fungi and protozoa

4. 4 Organisms that contaminate food
and cause foodborne illness

5. Acidity
Food
Temperature
Conditions that favor growth of
foodborne microorganisms
Moisture
Time
Oxygen

6. Bacteria
 Living, single celled organism
 Carried by food, water, soil, animals,
humans, insects
 Can survive freezing temps
 Can cause food spoilage and illness
 Can change form to protect themselves
when nutrients are unavailable - spores

7. Bacteria
 Bacteria are prokaryotes and have a characteristic cellular
organisation. They are simple, small, unicellular organisms,
varying in size between 1-20 um long
 Bacteria can be classified by shape:
Spherical (coccus) Spiral/helical Rod (bacilli)
e.g. Staphylococcus aureus e.g. Treponema e.g Escherichia coli

8. Salmonella
•Carried naturally by many farm animals
•Illness can occur from consuming only a small amount of contaminated food

9. Listeriosis (Listeria)
•Naturally found in soil, water, and plants
•Grows in cool, moist environments
•Pregnant women are especially vulnerable

10. Staphylococcal Gastroenteritis
•Primarily found in the hair, nose, throat, and sores of humans
•Cooking cannot destroy these toxins
•Practice good hygiene!

11. Botulism
•Bacteria is found commonly in produce grown in the soil
•Grows without oxygen and produces a deadly toxin
•Without treatment, can cause death

12. Hemorrhagic Colitis
•Caused by and more commonly referred to as E.Coli poisoning
•Produced toxins in the intestines
•Can be present in feces of infected persons for several weeks after symptoms appear

13. Viruses
 The smallest of microbial contaminants
 Cannot reproduce in food, but will produce
more viruses once in a human cell
 Can be transmitted from person to person,
people to food, and people to food-contact
surfaces
 Usually contaminate through a
foodhandler’s improper hygiene
 Classified as infections
 2 major viral foodborne illnesses: Hepatitis
A and Norovirus

14. Hepatitis A
•An infected person may not show symptoms for several weeks, but can be very infectious
•Found primarily in feces of those infected
•Cooking does not destroy the virus

15. Norovirus
•Very contagious virus
•Like Hepatitis A, it is transferred by touching food with fingers containing feces

16. Parasites
 Living organisms that need a host to
survive
 Larger than bacteria, yet still
microscopic
 Typically passed to humans through
animal host (cows, chickens, pigs, fish)

17. Anisakiasis
•Worm like parasite found in fish and shellfish
•Critical to cook seafood properly

18. Fungi
 Found naturally in air, soil, plants, water,
and some food.
 Examples: mold, yeast, mushrooms

19. Types of Fungi
Molds Yeast
 Responsible for spoilage of food  Ability to spoil food rapidly
 Results in odors, discoloration, and off  Produces carbon dioxide and alcohol
flavors – alcohol scent or flavor  May appear slimy, produce bubbles,
 Prefer to grow in and on acidic food and have a pink discoloration
with low water activity  Food spoiled by yeast should be
 Aflatoxin – produced by molds and discarded.
can cause liver disease  Found in jellies, jams, honeys, syrups,
 Corn products, peanut products, and fruit juice
tree nuts
 Throw away molded foods to prevent
illness
 FDA recommends cutting away at
least one inch areas around moldy
hard cheeses