To determine the safety of a high moisture bakery product, packaged under modified atmospheres, challenge studies were done on English-style crumpets (water activity [aw] 0.990, pH 6.5) inoculated postbaking with Clostridium botulinum types A and proteolytic B spores (5 X 102 spores/g).
Products were packaged either in air, in air with an Ageless FX200 oxygen absorbent, or in a CO2/N2 (60 : 40) gas mixture, stored at ambient temperature (25°C), and monitored for toxicity daily.
All inoculated crumpets were toxic within 4 to 6 days and were organoleptically acceptable at the time of toxigenesis.
Counts of C. botulinum increased to approximately 105 CFU/g at the time of toxicity.
To determine the effect of baking on product safety, subsequent challenge studies were done on crumpets inoculated with 5 X 102 spores/g (baked weight basis) prior to baking.
All crumpets were toxic after only 6 days, irrespective of packaging conditions, and toxigenesis again preceded spoilage.
Temperature profile studies showed that the maximum internal temperature reached during baking was 97°C, and the total baking process was equivalent to 0.03 min at 121°C. The actual time to toxin production in both studies (4 to 6 days) correlated well with the predicted time (3.4 days) using the U.S. Department of Agriculture Pathogen Modeling Program (version 5.1) for proteolytic strains of C. botulinum. (...)
Mots-clés Pascal : Mélange gaz, Pouvoir pathogène, Durée conservation, Clostridium botulinum, Clostridiaceae, Clostridiales, Bactérie, Produit cuisson, Atmosphère modifiée, Emballage, Toxine, Activité eau, Botulisme, Bactériose, Infection, Toxicité, Analyse sensorielle, Propriété organoleptique
Mots-clés Pascal anglais : Gas mixture, Pathogenicity, Shelf life, Clostridium botulinum, Clostridiaceae, Clostridiales, Bacteria, Bakery product, Modified atmosphere, Packaging, Toxin, Water activity, Botulism, Bacteriosis, Infection, Toxicity, Sensory analysis, Organoleptic properties
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 99-0337066
Code Inist : 002A35B03. Création : 16/11/1999.