Fundamental Food Microbiology, Third Edition - Fuad Fathir

78 FUNDAMENTAL FOOD MICROBIOLOGY
When the foods are exposed to temperatures beyond the maximum and minimum
temperatures of growth, microbial cells die rapidly at higher temperatures and
relatively slowly at lower temperatures. Microbial growth and viability are important
considerations in reducing food spoilage and enhancing safety against pathogens,
as well as in food bioprocessing. Temperature of growth is also effectively used in
the laboratory to enumerate and isolate microorganisms from foods.
IV. CONCLUSION
The physical and chemical environments control microbial growth within the growth
range mainly by influencing their metabolic process associated with synthesis of
energy and cellular components. Beyond the growth range, these factors, either
individually or in combination, can be used to control microbial growth and even
to destroy them. Actual growth is accomplished through the metabolism of various
nutrients present in a food. The processes by which the food nutrients are transported
inside the microbial cells and then metabolized to produce energy, cellular molecules,
and by-products are briefly discussed in Chapter 7.
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