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item Breidt, Frederick

Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 7/20/2004
Publication Date: 7/31/2004
Citation: Breidt, F., Costilow, R.N. 2004. Processing and safety. In: Acidified Foods: Principles of Handling and Preservation. St. Charles, IL: Pickle Packers International, Inc., p. 5-1-5-16.

Interpretive Summary: This is a chapter (Processing and Safety) for the manual, Acidified Food: Principles of Handling and Preservation, edited by Henry P. Fleming and Ralph N. Costilow. This manual is used for training operating supervisors who process acidified foods, as mandated by the acidified foods regulation CFR 21 part 114. This chapter provides new guidelines to assure that acid-tolerant food pathogens (Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella sp.) will be eliminated during the manufacture of acidified foods.

Technical Abstract: Acidified foods have an excellent safety record. The acid added to these products, along with the pasteurization treatments (thermal processes) that are used to assure preservation of many acidified foods, kill most spoilage and pathogenic (disease-causing) microorganisms. Thermal processes for acidified foods are designed to kill vegetative cells of microorganisms. It is important to note that the thermal treatments for these foods are not the same as sterilization because spores of bacteria, including spores of the deadly pathogen Clostridium botulinum, can easily survive such heat treatments. The germination and growth of C. botulinum and production of botulinum toxin is prevented in acidified foods by keeping the pH at or below 4.6. Some pathogenic bacteria, including Escherichia coli, Listeria monocytogenes, and Salmonella species are resistant to acid and low pH. Outbreaks of these pathogens have occurred in acid foods that were not thermally processed with pH values below 4.6, such as apple cider and orange juice. While these pathogens do not usually grow in acidified food products with pH values below 4.6, they may be able to survive for extended periods in some acidified vegetable products. Therefore, appropriate steps must be taken to be sure that these pathogenic bacteria, which do not produce spores, are killed in acidified foods.