Fundamental Food Microbiology, Third Edition - Fuad Fathir

SECTION IV
Microbial Food Spoilage
A food is considered spoiled when it loses its acceptance qualities. The factors
considered in judging the acceptance qualities of a food include color, texture, flavor
(smell and taste), shape, and absence of abnormalities. Loss of one or more normal
characteristics in a food is considered to be due to spoilage.
Food spoilage causes not only economic loss, but also loss of consumable foods.
In the U.S. and some other countries where foods are produced and procured from
many countries much more than the need, spoilage up to a certain level is not
considered serious. However, in many countries where food production is not efficient,
food spoilage can adversely affect the availability of food. With the increase
in world population, serious consideration needs to be given on not only increasing
food production but also reducing food spoilage, which for certain produce in some
countries could reach 25% or more.
The acceptance qualities of a food can be lost because of infestation with insects
and rodents, undesirable physical and chemical actions, and growth of microorganisms.
An example of physical spoilage is dehydration of fresh vegetables (wilting).
Chemical spoilage includes oxidation of fat, browning of fruits and vegetables, and
autolytic degradation of some vegetables (by pectinases) and fishes (by proteinases).
Microbial spoilage results either as a consequence of microbial growth in a food or
because of the action of some microbial enzymes present in a food. In this section,
food spoilage due to microbial growth and microbial enzymes is discussed under
the following topics:
Chapter 18: Important Factors in Microbial Food Spoilage
Chapter 19: Spoilage of Specific Food Groups
Chapter 20: New Food Spoilage Bacteria in Refrigerated Foods
Chapter 21: Food Spoilage by Microbial Enzymes
Chapter 22: Indicators of Microbial Food Spoilage