Skinner Guy E, Marshall Kristin M, Morrissey Travis R, Loeza Viviana, Patazca Eduardo, Reddy N Rukma, Larkin John W
U.S. Food and Drug Administration, Institute for Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501, USA.
Institute for Food Safety and Health, Illinois Institute of Technology, 6502 South Archer Road, Bedford Park, Illinois 60501, USA.
J Food Prot. 2014 Dec;77(12):2054-61. doi: 10.4315/0362-028X.JFP-14-259.
The aim of this study was to determine the resistance of multiple strains of the three nonproteolytic types of Clostridium botulinum (seven strains of type E, eight of type B, and two of type F) spores exposed to combined high pressure and thermal processing. The resistance of spores suspended in N-(2-acetamido)-2-aminoethanesulfonic acid (ACES) buffer (0.05 M, pH 7) was determined at a process temperature of 80°C with high pressures of 600, 650, and 700 MPa using a laboratory-scale pressure test system. Spores of C. botulinum serotype E strains demonstrated less resistance than nonproteolytic spores of type B or F strains when processed at 80°C and 600 MPa for up to 15 min. All C. botulinum type E strains were reduced by . 6.0 log units within 5 min under these conditions. Among the nonproteolytic type B strains, KAP 9-B was the most resistant, resulting in reductions of 2.7, 5.3, and 5.5 log, coinciding with D-values of 7.7, 3.4, and 1.8 min at 80°C and 600, 650, and 700 MPa, respectively. Of the two nonproteolytic type F strains, 610F was the most resistant, showing 2.6-, 4.5-, and 5.3-log reductions with D-values of 8.9, 4.3, and 1.8 min at 80°C and 600, 650, and 700 MPa, respectively. Pulsed-field gel electrophoresis was performed to examine the genetic relatedness of strains tested and to determine if strains with similar banding patterns also exhibited similar D-values. No correlation between the genetic fingerprint of a particular strain and its resistance to high pressure processing was observed.
本研究的目的是确定三种非蛋白水解型肉毒梭菌（7株E型、8株B型和2株F型）的多个菌株的芽孢在高压和热处理联合作用下的抗性。使用实验室规模的压力测试系统，在80°C的处理温度和600、650和700 MPa的高压下，测定悬浮于N-（2-乙酰氨基）-2-氨基乙烷磺酸（ACES）缓冲液（0.05 M，pH 7）中的芽孢的抗性。在80°C和600 MPa下处理长达15分钟时，E型肉毒梭菌菌株的芽孢比B型或F型菌株的非蛋白水解芽孢表现出更低的抗性。在这些条件下，所有E型肉毒梭菌菌株在5分钟内减少了6.0个对数单位。在非蛋白水解B型菌株中，KAP 9-B的抗性最强，在80°C和600、650和700 MPa下分别减少2.7、5.3和5.5个对数，对应的D值分别为7.7、3.4和1.8分钟。在两株非蛋白水解F型菌株中，610F的抗性最强，在80°C和600、650和700 MPa下分别减少2.6、4.5和5.3个对数，对应的D值分别为8.9、4.3和1.8分钟。进行脉冲场凝胶电泳以检查测试菌株的遗传相关性，并确定具有相似条带模式的菌株是否也表现出相似的D值。未观察到特定菌株的遗传指纹与其对高压处理的抗性之间存在相关性。
