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Germ Warfare

Germs are a fact of life. They are everywhere and in everything. Also known as pathogens or microorganisms, the primary group of this really bad stuff is Bacteria. These single-cell organisms reproduce in a process call Biarnary Fission where the cells split in two. The process takes approximately 20 minutes when the food the bacteria is between 40 and 140° F (the Temperature Danger Zone). So these bacteria reproduce exponentially in just a short time period! After 4 hours, the bacteria has reproduced to a level in which it will cause an illness if ingested.

The reproductive process has four stages:

(1) Lag Phase		The adjustment period for the bacteria when it is introduced to the food and is preparing to reproduce.
(2) Log Phase		The bacteria begins to split into two, doubling approximately every 20 minutes, dependent on temperature
(3) Stationary Phase		The number of bacteria growing begins to equal the number dying due to lack of nutrients
(4) Death Phase		The bacteria that are dying outnumber the bacteria that are growing

Keeping the reproductive process in mind, there are three categories of bacteria that thrive at different temperatures:

Bacteria	Range	Notable
Psychophilic	40 - 70°	Likes the cooler temps
Mesophilic	70 - 110°	Most bacteria fall in this category (30 min to reproduce)
Thermophilic	110 - 140°	Reproduces at different temperatures

As if that wasn't enough, bacteria can also be spore forming or non-spore forming. The main difference is the bacteria's ability to form a spore when the conditions become unfavorable. Once a spore is formed, it acts as an insulator to prolong the life of the cell, sending it into a vegetative state. Once the cell becomes vegetative, given time (i.e., 4 hours) toxins can form.

One spore forming bacteria - Clostridium botulinum - forms in an anaerobic environment (without oxygen) and occurs in underprocessed and low acid foods. For this reason, home-canned products are not used in commercial kitchens as the canning process cannot be measured against any standards and may, however inadvertently, be open to producing botulism.

But enough about bacteria! There are other germs! Below is a brief list and descriptions...

Pathogen	Description	Example
Virus	The smallest of pathogens; Requires a living host. Most commonly transmitted via improper food handling.	Salmonella
Parasite	Lives on or in a host; Proper cooking will kill parasites. Trichinella commonly found in hogs, bears and walrus.	Botulism
Fungi	Wild mushrooms and most molds; Cheese and yogurt are good molds, however.	E. coli

Seafood is one of the more succeptable to biological contanmination. Ciguatera toxins occur in coastal and tropic reef fish such as amberjack, barracuda and grouper. Ciguatera appears when the fish has ingested smaller fish that feed on algae that has been infected with toxins. Scombroid poisoning, however, is a common foodborne illness among fish that is consumed in the United States. This poisoning is the result of time-temperature abuse.

For a summary of some of the more popular pathogens, download this spreadsheet.

Fallout from Germ Warfare
Of course if you get stuck with one of the above microorganisms, you are going to get sick. Below is a comparison of terms that apply to Foodborne Illnesses:

Illness	Description
Foodborne Illness	A disease that is carried or transmitted by food.
Outbreak of Foodborne Illness	An occurance of two or more people suffering from the same illness after eating the same food.
Food Infection	The result of consuming a food containing pathogens that grow in the intestine.
Food Intoxication	The result of consuming pathogens with toxins that will make you sick immediately.
Toxin-Mediated Infection	The result of consuming pathogens that release toxins after consumption that will make you sick.

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