THERMAL INACTIVATION OF CLOSTRIDIUM-BOTULINUM TYPE-E SPORES IN OYSTER HOMOGENATES AT MINIMAL PROCESSING TEMPERATURES

D‐values of Clostridium botulinum type E in oyster homogenates were calculated from the slopes of survivor curves for each variable tested (control, 1.0% NaCl, 0.13% potassium sorbate (KS), and a combination of NaCl and KS) at five temperatures. Mean D‐values ranged from 0.78 min at 80°C to 7943 min at 50°C. The addition of salt and/ or KS affected heat resistance of the spores, but differences were not consistent among the temperatures tested, z‐Values calculated for the curve between 70°C and 80°C ranged from 6.9 C° to 7.6 C°, while z‐values calculated for the curve between 55°C and 70°C were 12.1–14.70°. These data indicate that C. botulinum type E would survive in oysters that are minimally processed. A suitable process could be determined using the data presented; however, oysters would have a cooked appearance. Copyright © 1990, Wiley Blackwell. All rights reserved