Beterams Anja, Kirse Alina, Kreienbrock Lothar, Stingl Kerstin, Bandick Niels, Reich Felix
Department of Biological Safety, German Federal Institute for Risk Assessment, Berlin, Germany.
Institute of Biometry, Epidemiology and Information Processing (IBEI), WHO Collaborating Centre for Research and Training for Health at the Human-Animal-Environment Interface, University of Veterinary Medicine Hannover, Hanover, Germany.
Front Microbiol. 2024 Sep 19;15:1429756. doi: 10.3389/fmicb.2024.1429756. eCollection 2024.
Two physical treatments (heat via water bath and cold air) with various temperatures (20/70/75/80°C and - 80/-90°C) and exposure times (20, 30, 40 s) were carried out to identify a decontaminating effect on zoonotic pathogens on broiler carcasses. Subsequently, carcasses were analyzed for thermotolerant , , and total colony count (TCC). Moreover, for the hot water treatment, qPCR with viable/dead differentiation (v-qPCR) was applied to detect viable but non-culturable cells (VBNC) of referred to as intact but putatively infectious units (IPIU). Hot water immersion was tested on carcasses inoculated with and , while cold air treatment was evaluated for naturally contaminated carcasses of broiler flocks colonized with . For hot water treatment, the statistically significant reducing effect was about 1 log CFU/ml for both and for 70-80°C and 20/30 s treatments. The effect of heat treatment for was smaller when samples were analyzed with v-qPCR with reductions of 0.5-0.8 log IPIU/ml in mean. Cold air treatments at -90°C were effective in reducing the mean contamination level of by 0.4-0.5 log CFU/ml at all exposure times ( < 0.05). Hot water treatments showed a decreasing trend on TCC by 0.6-0.9 log CFU/ml (p < 0.05). TCC counts were not significantly affected by cold air treatment. For no statistically significant reductions were observed by hot water treatment. The cold air treatment at -90°C for 20 and 40 s led to a reduction of by 0.4 and 0.8 log CFU/ml ( < 0.05), respectively. Treatment of carcasses with higher bacterial levels tended to show higher reduction. The research demonstrated that the efficacy of physical treatments for decontamination of broiler carcasses was more pronounced for hot water immersion than for cold air exposure. In conclusion, the results shed light on the potential application of these physical treatments in practice to reduce the quantitative load of contaminating pathogens to enhance food safety in the broiler meat production.
进行了两种物理处理（水浴加热和冷空气处理），设置了不同温度（20/70/75/80°C和−80/−90°C）和暴露时间（20、30、40秒），以确定对肉鸡胴体上人畜共患病原体的去污效果。随后，对胴体进行耐热菌、[此处原文缺失部分内容]和总菌落数（TCC）分析。此外，对于热水处理，应用具有活菌/死菌区分功能的定量聚合酶链反应（v-qPCR）来检测[此处原文缺失部分内容]的活但不可培养细胞（VBNC），即完整但可能具有传染性的单位（IPIU）。在接种了[此处原文缺失部分内容]和[此处原文缺失部分内容]的胴体上测试了热水浸泡处理，而对感染了[此处原文缺失部分内容]的肉鸡群的自然污染胴体评估了冷空气处理效果。对于热水处理，在70 - 80°C和20/30秒处理条件下，[此处原文缺失部分内容]和[此处原文缺失部分内容]的统计学显著降低效果约为1 log CFU/ml。当用v-qPCR分析样品时，[此处原文缺失部分内容]热处理的效果较小，平均降低0.5 - 0.8 log IPIU/ml。在所有暴露时间下，−90°C的冷空气处理有效降低了[此处原文缺失部分内容]的平均污染水平，降低幅度为0.4 - 0.5 log CFU/ml（P < 0.05）。热水处理使TCC呈下降趋势，降低幅度为0.6 - 0.9 log CFU/ml（P < 0.05）。冷空气处理对TCC计数无显著影响。对于[此处原文缺失部分内容]，热水处理未观察到统计学显著的降低。−90°C处理20秒和40秒的冷空气处理分别使[此处原文缺失部分内容]降低了0.4和0.8 log CFU/ml（P < 0.05）。细菌水平较高的胴体处理后往往显示出更高的降低幅度。该研究表明，物理处理对肉鸡胴体去污的效果在热水浸泡处理中比冷空气暴露更为明显。总之，这些结果揭示了这些物理处理在实践中的潜在应用，以减少污染病原体的定量负荷，提高肉鸡生产中的食品安全。
