most bacteria prefer a neutral environment (pH 7.0) but are capable of growing in foods that have a pH in the range of 4.6 to 7.0

(a)  

all bacteria do not have the same temperature requirements for growth

(a)  

grow within a temperature range of 32oF (0oC) to 70oF (21oC). These microorganisms are especially troublesome because they are capable at both refrigerated and room temperature.

(a)  

bacteria grow at temperatures between 70oF (21oC) to 110oF (43oC) with most rapid growth at human body temperature (98.6oF (37oC).

(a)  

grow best at temperature above 110oF (43oC). They are spoilage organisms.

(a)  

bacteria needed about 4 hours to grow to high enough numbers to cause illness

(a)  

bacteria also differ in requirements for oxygen

(a)  

bacteria must have oxygen in order to grow

(a)  

bacteria cannot survive when oxygen is present

(a)  

forms of bacteria can grow with or without oxygen but have a preference. Most foodborne disease causing-bacteria are anaerobes.

(a)  

have a very specific oxygen requirements usually in the range of 3% to 6%.

(a)  

amount of available water for bacterial activity.

(a)