Clostridium botulinum and the safety of refrigerated processed foods of extended durability

Refrigerated processed foods of extended durability (e.g. sous-vide foods) rely on a mild heat treatment followed by storage at chill temperature for safety and preservation. The principal microbiological hazard in such foods is growth of nonproteolytic Clostridium botulinum. Recent research has identified combinations of mild heat treatment and subsequent refrigerated storage that, when combined with a specified shelf life, provide a defined safety margin with respect to nonproteolytic C. botulinum. This article discusses microbiological concerns associated with such minimally processed foods, describes recent studies of factors affecting the survival and growth of non-proteolytic C. botulinum, and focuses on the use of combination processes to ensure product safety.