细菌孢子具有很高的弹性,普遍存在于地球上,一旦复活恢复营养生长,就会不可逆转地进入食物链,导致食物腐败或食源性疾病。传统上,广泛的热处理已被用来有效地杀死孢子;然而,相对较高的热负荷对食品质量属性产生不利影响。近年来,基于发芽可以降低孢子弹性的情况,已经开发了发芽失活策略来温和地杀死孢子。然而,未能诱导所有孢子分化,主要是由于孢子的异质萌发行为,阻碍了这一战略在食品工业中的成功应用。毫无疑问,阐明详细的发芽途径和潜在的机制可以填补我们理解发芽异质性的空白,从而促进全面发芽方案的发展,以温和地杀死孢子。在这次审查中,我们全面讨论了芽孢杆菌和梭菌孢子萌发的机理,并更新早期发芽事件的分子基础,例如,发芽受体的激活,离子释放,Ca-DPA释放,和分子事件,结合最新的研究证据。此外,高静水压力(HHP),先进的非热食品加工技术,也可以引发孢子萌发,为发芽-失活策略在HHP加工中的应用提供了依据。这里,我们还总结了芽孢杆菌和梭菌在HHP下孢子的萌发行为和机理。目的是促进HHP作为一种温和的加工技术,可能在食品灭菌中应用。实际应用:这项工作为开发食品工业中细菌孢子的有效杀灭策略提供了基础。
Bacterial spores are highly resilient and universally present on earth and can irreversibly enter the food chain to cause food spoilage or foodborne illness once revived to resume vegetative growth. Traditionally, extensive thermal processing has been employed to efficiently kill spores; however, the relatively high thermal load adversely affects food quality attributes. In recent years, the germination-inactivation strategy has been developed to mildly kill spores based on the circumstance that germination can decrease spore-resilient properties. However, the failure to induce all spores to geminate, mainly owing to the heterogeneous germination behavior of spores, hampers the success of applying this strategy in the food industry. Undoubtedly, elucidating the detailed germination pathway and underlying mechanism can fill the gap in our understanding of germination heterogeneity, thereby facilitating the development of full-scale germination regimes to mildly kill spores. In this review, we comprehensively discuss the mechanisms of spore germination of Bacillus and Clostridium species, and update the molecular basis of the early germination events, for example, the activation of germination receptors, ion release, Ca-DPA release, and molecular events, combined with the latest research evidence. Moreover, high hydrostatic pressure (HHP), an advanced non-thermal food processing technology, can also trigger spore germination, providing a basis for the application of a germination-inactivation strategy in HHP processing. Here, we also summarize the diverse germination behaviors and mechanisms of spores of Bacillus and Clostridium species under HHP, with the aim of facilitating HHP as a mild processing technology with possible applications in food sterilization. Practical Application: This work provides fundamental basis for developing efficient killing strategies of bacterial spores in food industry.