Retort Cooling Water Bact- eriological Load and Possible Mitigation Strategies for Microbial Buildup in Cooling Water

There has been a concern that Clostridium botulinum might enter a defective can of low-acid food through a microleak after thermal processing and during the cooling process. This paper reviews most current surveys on bacteriological quality of cannery cooling water, bacteriological testing methods in cannery cooling water, disinfection of container cooling water in canning systems, and common types and methods of disinfection. The Grocery Manufacturers Association (GMA) survey of cooling water systems currently used in industry showed a high percentage of routine microbial testing and chemical treatments. Published reports on the microbiological conditions of the retort cooling water indicated that containers may be sufficiently protected against leaker spoilage only if the aerobic plate count (APC) of the cooling water is less then 100 CFU per ml. Disinfection of all cooling water systems, including single pass systems, is recommended when APC loads exceed 100 CFU/ml. Microbial testing and cooling water treatments may be included in an operational or standard operation procedure to control microbial buildup in retort cooling water and reduce the possibility of post-process contamination. Food Protection Trends, Vol. 30, No. 3, Pages 160–167 Copyright© 2010, International Association for Food Protection 6200 Aurora Ave., Suite 200W, Des Moines, IA 50322-2864 ARTICLES