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bbqjoe
05-23-2006, 10:50 AM
Most bacteria require six elements in order to grow/reproduce.
The question is this: Which six are most critical for growth?



I used the word critical, but I belive the word should have been crucial.

__________________________________________________ ________________________________
Here are the answers.

Food
Acidity
Temperature
Time
Oxygen
Moisture

BACTERIA

Bacteria are everywhere. Most bacteria are useful like those used in the production of yogurt, cheese and sourdough bread, but some are very harmful. These harmful bacteria are called pathogenic bacteria; that is they make people sick. By far, of all microorganisms bacteria are the biggest concern contributing to most foodborne illness cases. Most bacteria are controlled by storing, cooking, and cooling food properly.

Characteristics of Bacteria:
They are single cell organisms
They may be carried by a variety of means: food, water, soil, humans, or insects
Under favorable condition they produce rapidly (temperature danger zone, 41°F and 135°F).
Some can survive refrigeration and freezing temperatures.
Some cause food spoilage, other cause illness.
Some cause illness by producing poisonous toxins. Heating cannot destroy these toxins.

What Microorganisms Need to Grow (FAT TOM):
FOOD – Proteins and Carbohydrates
ACIDITY: Pathogenic bacteria grow best in foods that are slightly acidic (pH of 4.6-7.5)
TEMPERATURE: Pathogenic bacteria grow best between 41°F and 135°F (the danger zone). This is why leaving food at room temperature for several hours is very dangerous. Note: Foods left outside the danger zone doesn’t necessary kill microorganisms, for example, refrigeration temperature doesn’t necessary kill microorganisms but just slow their growth.
TIME: When organisms are given favorable temperatures, proper nutrients and water they can double in population as quickly as every 20 minutes. If foods are left in the danger zone for 4 hours or more microorganisms can grow enough to make someone ill.
OXYGEN: Some microorganisms need oxygen to grow and some can grow in the absence of oxygen.
MOISTURE: Most microorganisms require water to grow therefore they grow well in moist food. Potentially hazardous foods grow best with a .85 or higher water activity level.

Yakfishingfool
05-23-2006, 12:41 PM
This has been great stuff Joe, keep up the good work. Scott

bbqjoe
05-24-2006, 12:35 PM
Any thoughts here people?
Any questions?

bigabyte
05-24-2006, 01:26 PM
That was some really good info Joe. Thanks for posting that. I guessed Alkalinity, because I knew pH woudl be a factor, but I guessed wrong. Now I know better. I got the others right, but they were the easy ones. Good music never hurt anybody!

CharlieBeasley
05-24-2006, 01:29 PM
The big surprise to me was the acidity I would not have though that would promote growth. Thanks Joe!

djmarko
05-25-2006, 11:08 AM
Does that danger zone apply to fully cooked food as well as raw? Just thinking about cooked food that might be left out on a warm day.