Food Antimicrobials - An Introduction, P. Davidson and A. Branen Sodium Benzoate and Benzoic Acid, J. Chipley Sorbic Acid and Sorbates, J. Stopforth, J. Sofos, and F. Busta Organic Acids, S. Doores Sulfur Dioxide and Sulfites, C. Ough and L. Were Nitrite, R. Tompkin Nisin, L. Thomas and J. Delves-Broughton Natamycin, J. Delves-Broughton, L. Thomas, P. Davidson, and C. Doan Parabens, P. Davidson Dimethyl Dicarbonate and Diethyl Dicarbonate, D. Golden, R. Worobo, and C. Ough Medium-Chain Fatty Acids and Esters, J. Kabara, D. Marshall Lysozyme, E. Johnson and A. Larson Bacteriocins with Potential for Use in Foods, D. Hoover and H. Chen Naturally Occurring Compounds - Plant Sources, A. Vigil, S. Alzamora, and E. Palou Naturally Occurring Compounds - Animal Sources, J. Stopforth, P. Skandamis, P. Davidson, and J. Sofos Sanitizers: Halogens, Surface-Active Agents, and Peroxides, B. Cords, S. Burnett, J. Hilgren, and J. Magnuson Indirect and Miscellaneous Antimicrobials, L. Shelef and J Seiter Antibiotic Residues in Foods and Their Significance, S. Katz and P. Ward Hurdle Technology Approaches to Food Preservation: Current Applications, Prerequisites and Pitfalls, L. Leistner and G. Gould Mechanisms of Action, Resistance, and Stress Adaptation, A. Russell Methods for Activity Assay and Evaluation of Results, A. Vigil, E. Palou, M. Parish, and P. Davidson

Antimicrobials in Food

Growth and Inhibition of Microorganisms in the Presence of Sorbic Acid: A Review

Surface microbial stability is a major determinant of the shelf life of refrigerated meat products. Surface microbial growth has also been noticed in intermediate moisture foods exposed to temperature fluctuations. One solution to this problem is to apply edible coatings to the food surface which control diffusion of antimicrobial agents into the food. Films with such properties were identified using a permeability cell. Methyl- and hydroxypropyl methylcellulose mixed with lauric, palmitic, stearic and arachidic acid significantly lowered the potassium sorbate permeation rate relative to cellulose ether films containing no fatty acids. Permeability determinations at 5, 24, 32 and 40°C showed excellent agreement with the Arrhenius activation energy model for the permeation process.

Potassium Sorbate Permeability of Methylcellulose and Hydroxypropyl Methylcellulose Coatings: Effect of Fatty Acids

Sorbic acid (2,4-hexadienoic acid) and its salt, sorbate, have been used in the preservation of food products since the 1940s. While it can be isolated naturally from rowanberries (mountain ash tree), that used in foods is chemically synthesized. Sorbates have regulatory approval throughout the globe for application as antimicrobial preservatives for foods, animal feeds, pharmaceuticals, and cosmetics. Sorbate has efficacy against many bacteria, molds, and yeasts but has historically been used primarily as an antifungal agent in foods. Because it is a weak acid (pKa = 4.76) and the most effective antimicrobial form is the undissociated acid, sorbate activity is greatest at lower pH. Thus it is more consistently effective as an antimicrobial in foods with pH < 5.0–5.5. While it is inhibitory to most molds, some, including species of Penicillium, Aspergillus, Fusarium, Mucor, and Geotrichum, have the ability to metabolize sorbates and produce off-odors. Subjects covered in this chapter include the chemical and physical characteristics of sorbates, their antimicrobial activity spectrum (including interactions with food components, degradation, and mechanisms of action), application of the compounds to dairy, vegetable, fruit, bakery, meat, and other miscellaneous products, safety and toxicology of the compounds, detection and analysis methods, and regulatory status.

C. N. Huhtanen

Papers

Acid Enhancement of Clostridium botulinum Inhibition in Ham and Bacon Prepared with Potassium Sorbate and Sorbic Acid.