Van Houteghem Nancy, Devlieghere Frank, Rajkovic Andreja, Gómez Sandra Maria Osés, Uyttendaele Mieke, Debevere Johan
Department of Food Safety and Food Quality, Laboratory of Food Microbiology and Food Preservation, Ghent University, Coupure links 653, B-9000 Ghent, Belgium.
Int J Food Microbiol. 2008 Mar 31;123(1-2):67-73. doi: 10.1016/j.ijfoodmicro.2007.12.002. Epub 2007 Dec 23.
To assure the microbiological safety and quality of a food product, a combination of preservation hurdles is often used. Therefore, the effects of carbon dioxide at concentrations of 0, 20, 40 and 60% in modified atmospheres on the resuscitation of Listeria monocytogenes cells injured by mild bactericidal treatments during storage at 7 degrees C were examined. The bactericidal treatments were intense light pulses (ILP), chlorine dioxide (ClO(2)), lactic acid (LA) and heat. The results indicated additional bactericidal effects of CO(2) on cultures treated with LA, ClO(2) and ILP, with additional reductions in viable L. monocytogenes of 0.5-1.0 log cfu/ml. Lag phase duration was significantly different between the different treatments, with non-treated cells having the shortest lag phase, followed by that of heat, intense light pulses, lactic acid and finally ClO(2) treated cells. Maximum growth rate was also estimated and results showed a negative correlation with increasing CO(2) concentrations. A relationship was found between the amount of sub-lethally damaged cells after a mild inactivation treatment and the lag phase duration in the CO(2) environment. Current findings demonstrate the possibility that combining mild decontamination treatments and packaging in a CO(2) enriched environment could reduce the risk of L. monocytogenes infections in food due to an extension of the lag phase.
为确保食品的微生物安全性和质量，通常会采用多种保鲜障碍措施的组合。因此，研究了在7℃储存期间，在气调包装中二氧化碳浓度分别为0%、20%、40%和60%时，对经温和杀菌处理损伤的单核细胞增生李斯特菌细胞复苏的影响。杀菌处理包括强光脉冲（ILP）、二氧化氯（ClO₂）、乳酸（LA）和加热。结果表明，二氧化碳对经乳酸、二氧化氯和强光脉冲处理的培养物具有额外的杀菌作用，可使单核细胞增生李斯特菌的活菌数进一步减少0.5 - 1.0 log cfu/ml。不同处理之间的延滞期持续时间存在显著差异，未处理的细胞延滞期最短，其次是加热处理的细胞、强光脉冲处理的细胞、乳酸处理的细胞，最后是二氧化氯处理的细胞。还估计了最大生长速率，结果表明其与二氧化碳浓度的增加呈负相关。在温和灭活处理后亚致死损伤细胞的数量与二氧化碳环境中的延滞期持续时间之间发现了一种关系。目前的研究结果表明，在富含二氧化碳的环境中结合温和的去污处理和包装，有可能因延长延滞期而降低食品中单核细胞增生李斯特菌感染的风险。
