Comparison of experimentally obtained generation times of ent+ and ent- grown in autoclaved beef with those predicted by the Gompertz model (shortest known cellular doubling time)

Range Table - link
Organism Bacteria Clostridium perfringens
Reference Labbe R.G., Huang T.H. Generation times and modeling of enterotoxin-positive and enterotoxin-negative strains of Clostridium perfringens in laboratory media and ground beef. J. Food Prot. 1995 58 (12) 1303–1306. Table 2 page 1305
Method The growth of two enterotoxin-positive (ent+) and two enterotoxin-negative (ent-) strains of Clostridium perfringens were examined in two laboratory media, fluid thioglycollate and fluid thioglycollate with beef, and in autoclaved ground beef stored at 37, 41, 43, 46, and 48°C. There was no association between enterotoxigenicity and optimum growth temperature, which varied depending on strain and medium. Experimentally obtained values for generation times at 43°C were as low as 8.7 and 6.3 min in thioglycollate both for ent+ and ent- strains respectively. In autoclaved ground beef the shortest generation times, 7.1 min and 9.2 min, were obtained at 41 and 46°C for two ent+ strains. For ent- strains in autoclaved ground beef a generation time of 6.6 min was observed at 43°C. Temperature optima obtained experimentally were the same as those obtained by the Gompertz model (For Gompertz model see: Buchanan, R. 1991. 'Using spreadsheet software for predictive micro-biology applications' J. Food Safety 11:123-134 AND Whiting, R. and R. Buchanan. 1994. Microbial Modeling. Food Technol. 48: 113-120)
Comments The rapid growth of the ent+ strains between 41 and 46°C underlines previous recommendations for proper holding and cooling of protein foods such as meat and poultry known to support the growth of this organism. For doubling time of 6.3±0.4min from this work see BNID 105469. See BNID 105473
Entered by Uri M
ID 105474