FS 125
March 10, 2012
ANTIMICROBIAL AGENTS 1. Introduction Food preservation has long been practiced since the olden times with processes such as heating , drying, fermentation and refrigeration. In spite of this, physical methods are not enough to eliminate all microorganisms found in foods. Therefore, antimicrobial agents are needed to destroy these foodborne pathogens, so that the food will have a longer shelf-life. As technology progresses, improvements in the processing procedure and packaging systems considerably contribute to the preservation of food. Even so, antimicrobial agents still play an important role in protecting the food supply.
Antimicrobial agents are chemical compounds biosynthetically or synthetically produced which either destroy or usefully suppress the growth or metabolism of a variety of microscopic or submicroscopic forms of life.
2. Factors Affecting the Selection of Antimicrobial agents 2.1 Antimicrobial activity against different organisms It is desirable to use an antimicrobial agent that can inhibit a wide range of spoilagecausing microorganism. A good understanding of the chemicals' mode of action is also useful in selecting a preservative.
2.2 Microbial load of the food product . The food must be of the highest microbiological quality initially. Food should always be processed under the most meticulous sanitary conditions to minimize contamination. A high microbial population would require higher doses of antimicrobial agents. Use of antimicrobial agents should not be viewed as a substitute for good sanitation.
2.3. Chemical and physical properties In choosing an antimicrobial agent, properties such as solubility, boiling point, and dissociation are important. Water solubility is important since microbial growth requires water.
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Volatile preservatives are easily lost if the food is heated during processing. Dissociation of sorbic acid has an important bearing on its