BEHAVIOR OF NONPROTEOLYTIC CLOSTRIDIUM-BOTULINUM TYPE-B AND TYPE-E SPORES IN COOKED TURKEY AND MODELING LAG PHASE AND PROBABILITY OF TOXIGENESIS

A spore pool inoculum (I) of 4 each type B and E nonproteolytic C. botulinum was applied at levels of log10-2 to 4 spores per 2-3g sample of cooked turkey (0, 1.47, and 2.2% brine (B), respectively), stored under vacuum at 4, 8, 12, 16, 20, and 30-degrees-C up to 180 days. Earliest toxin production at the above temperatures (T) was detected in 0% brine meat after > 180, 8, 4, 1.5, 1.5, and 0.5 days, in the 1.47% brine after 70, 8, 7, 2, 1.5 and 1 days, and in the 2.2% brine after 130, 10, 9, 2.5, 1.5 and 1 days, respectively. Lag phase (LP) was affected significantly by T, I, and T x I (p < 0.001) but not B (0.05 < p < 0.1). The derived model predictive of LP was: Log10 LP = 0.625 + 6.710 (1/T) + 0.005 (I) x (T) - 0.033 (T) + 0.102 (B) - 0.102 (I) with R2 = 0.970. More precise sampling plans and augmentation of our dataset will increase confidence in the model.