b. How does this relate to the food a person eats? Meat falls in the middle of
the pH scale--the area where microorganisms grow freely. Most fruits contain a great
deal of acid; most vegetables are alkaline. This makes meats a very likely source of
ACID
NEUTRAL
ALKALINE
FRUITS
MEATS
VEGETABLES
1-10. TEMPERATURE REQUIREMENTS OF BACTERIA
a. Bacteria must have a suitable temperature in order to reproduce. Bacterial
growth can be controlled by controlling temperature.
b. Bacteria can be divided into three major groups based upon temperature
requirements. These three groups are: bacteria that respond to high temperatures;
bacteria that respond to moderate temperatures; and bacteria that respond to cool
temperatures.
(1) Bacteria that grow best at high
temperatures are called thermophilic
bacteria. They thrive at temperatures
of 110F to 140F.
(2) Bacteria that grow best at moderate
temperatures are termed mesophilic
bacteria. They thrive at temperatures
of 60F to 110F.
(3) Bacteria that grow best at cool
temperatures are termed
psychrophilic bacteria. They thrive
at temperatures of 32F to 45F.
c. In addition to these three major groups, there are other bacteria able to
withstand extremely high temperatures. These are called heat-resistant or
thermoduric bacteria. The spores of thermoduric bacteria can even survive boiling.
MD0181
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