Two distinct groups within the Bacillus subtilis group display significantly different spore heat resistance properties
Two distinct groups within the Bacillus subtilis group display significantly different spore heat resistance properties
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DOI:
10.1016/j.fm.2014.04.009
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发表时间:
2015-02-01
影响因子:
5.3
通讯作者:
Wells-Bennik, Marjon H. J.
中科院分区:
文献类型:
--
作者:
Berendsen, Erwin M.;Zwietering, Marcel H.;Wells-Bennik, Marjon H. J.
The survival of bacterial spores after heat treatment and the subsequent germination and outgrowth in a food product can lead to spoilage of the food product and economical losses. Prediction of time-temperature conditions that lead to sufficient inactivation requires access to detailed spore thermal inactivation kinetics of relevant model strains. In this study, the thermal inactivation kinetics of spores of fourteen strains belonging to the Bacillus subtilis group were determined in detail, using both batch heating in capillary tubes and continuous flow heating in a micro heater. The inactivation data were fitted using a log linear model. Based on the spore heat resistance data, two distinct groups (p < 0.001) within the B. subtilis group could be identified. One group of strains had spores with an average D-120 (degrees C) of 0.33 s, while the spores of the other group displayed significantly higher heat resistances, with an average D-120 degrees C of 45.7 s. When comparing spore inactivation data obtained using batch-and continuous flow heating, the z-values were significantly different, hence extrapolation from one system to the other was not justified. This study clearly shows that heat resistances of spores from different strains in the B. subtilis group can vary greatly. Strains can be separated into two groups, to which different spore heat inactivation kinetics apply. (C) 2014 Elsevier Ltd. All rights reserved.