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Keeping Foods and Beverages Safe
By Michael Kralik, PhD
Within the food and beverage industries, the primary control measure used to preserve the freshness and prevent spoilage is the pasteurization process. Spoilage bacteria are always present in the processing of food materials, and usually will not induce illness if ingested. However, pathogenic bacteria will cause illness, and foods left exposed at unsafe temperatures in the “Danger Zone” between 40º F and 140ºF for extended periods could be dangerous to eat. In general, it only takes twenty minutes for bacteria to double in number; so, that pitcher of juice, potato salad, or bottle of dressing could become a toxic microbial side dish in very little time at room temperature.
Proper handling, preparation, and preservation of foods readily control common pathogens like Escherichia coli O157:H7, Salmonella, Staphylococcus, Streptococcus spp., and Pseudomonas aeruginosa, which is an opportunistic pathogen. As such, the Food and Drug Administration (FDA) has outlined preparative control procedures to ensure the safety of food products. They require manufacturing plants to ensure that the processing conditions of foods results in at least a 5-Log reduction of microbial species present in the foods. This does not mean that the microorganisms present are completely eliminated, just that they are controlled so that continued careful handling will prevent food borne illness.
To extend the shelf-life of ingestible products, manufacturers frequently rely upon the addition of preservatives to processed foods. They are added to compensate for the consumer who may open and close a bottle or jar multiple times, and with each opening inoculate the food with environmental microbiological contaminants. Without the preservatives, the food would spoil very quickly and would have to be disposed of. Just think of how many times a bottle of salad dressing may be opened and closed again before being fully consumed!
Preservatives, however, should never be added to compensate for a faulty processing system. Manufacturers must ensure that their water systems and all the control steps, such as sanitation and pasteurization (typical batch pasteurization is at a temperature of >145º F for 30 minutes or HTST at 185º F for 15 seconds), are implemented with processing and packaging systems to bring the finished product into a compliant and safe microbial status, prior to preservatives being added.
Story Source: The above story is reprinted from materials provided by Michael Kralik, PhD (with editorial adaptations by Natural Products Foundation staff). Dr. Kralik is the current Director of Corporate Quality at Alix Technologies, Inc.