24-2 |
Natural or formulated antimicrobials |
V. K. JUNEJA, Microbial Food Safety Research, USDA-ARS-Eastern Regional Research Center, 600 E. Mermaid Ln., Wyndmoor, PA 19038-8598 Food preservation to ensure food safety continues to be a challenge for the food industry and regulatory agencies. Among the strategies used to achieve food preservation by inhibiting growth of undesirable microorganisms, is the use of chemical agents exhibiting antimicrobial activity. These chemicals may be either synthetic compounds intentionally added to foods or naturally occurring, biologically-derived substances. These substances may exhibit antimicrobial properties in the foods in which these normally are found or may be used as hurdles in multifactor food preservation systems. Factors to be taken into account for use in food products include: (1) physical and chemical properties of the antimicrobial such as chemical reactivity, solubility, dissociation constant (pKa), and toxicity; (2) composition and properties of the food to be preserved; and (3) the types and numbers of microorganisms to be controlled. An ideal antimicrobial should not contribute to the development of resistant strains. The mode of action of antimicrobials falls into one of three categories: (1) reaction with the cell membrane, causing increased permeability and loss of cellular constituents; (2) inactivation of essential enzymes; or (3) destruction or functional inactivation of genetic material. While no antimicrobial are able to preserve a product that is grossly contaminated, the use of combinations of preservatives and processes is likely to remain an important strategy in food preservation to meet consumers demand for wholesome and safe foods.
Session 24, Packaging tackles food safety: A look at antimicrobials
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