Hazard and control of group II (non-proteolytic) Clostridium botulinum in modem food processing

Group 11 (non-proteolytic) Clostridium botulinum poses a safety hazard in modem food processing, which consists of mild pasteurization treatments, anaerobic packaging, extended shelf lives and chilled storage. The high risk is reflected in the relatively large number of botulism cases due to group 11 C. botulinum in commercially produced foods during the past decades. Because of the high prevalence of group 11 C. botulinum in the environment, food raw materials may carry spores. Although group 11 spores are less heat-resistant than group I (proteolytic) spores, they can tolerate the heat treatments employed in the chilled food industry. Some food components may actually provide spores with protection from heat. Spore heat resistance should therefore be investigated for each food in order to determine the efficiency of industrial heat treatments. Group 11 strains are psychrotrophic and thus they are able to grow at refrigeration temperatures. Anaerobic packages and extended shelf lives provide C botulinum with favourable conditions for growth and toxin formation. As the use of salt and other preservatives in these foods is limited, microbiological safety relies mainly on refrigerated storage. This sets great challenges on the production of chilled packaged foods. To ensure the safety of these foods, more than one factor should safeguard against botulinal growth and toxin production. (c) 2005 Elsevier B.V. All rights reserved.