Hart Abarasi, Anumudu Christian, Onyeaka Helen, Miri Taghi
School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT UK.
J Food Sci Technol. 2022 Feb;59(2):417-428. doi: 10.1007/s13197-021-05022-7. Epub 2021 Feb 16.
Extending shelf-life of food, ensuring it is safe for consumers and meeting regulatory standards is the food industry's governing principle. Food safety is an essential aspect of food processing. Spores-forming microbes such as Bacillus spp. and Clostridium spp. are problematic in the food industry because of their ability to form endospores and survive processing conditions. Hence, their germination in food poses a threat to both shelf-life and safety of food. This paper reports on the current state of supercritical fluid carbon dioxide (SF-CO) application in the inactivation of spores-forming microbes in food. Unlike high hydrostatic pressure and thermal processes which struggle to deactivate and destroy spores, and if they do, it impacts adversely on the food nutritional and quality attributes. This technique is viable to inactivate spores and maintain the foods structural and nutritional characteristics. The mechanisms of inactivation can be grouped into: (1) release of cellular content due to rupture of the cell wall, coat and cortex, and disruption of membranes, (2) degradation of proteins as a result of interaction with permeated and penetrated SF-CO and (3) deactivation of enzymatic activities. It was discovered that the synergistic effect of ultrasound another non-thermal technique or addition of co-solvent such as water, hydrogen peroxide and ethanol or antimicrobial peptide greatly enhanced inactivation of spores. This work harmonizes published perspectives on spores' inactivation mechanisms, and will help inform further research into the application of SF-CO in the sterilization of food products.
延长食品保质期、确保其对消费者安全并符合监管标准是食品行业的指导原则。食品安全是食品加工的一个重要方面。形成芽孢的微生物，如芽孢杆菌属和梭菌属，在食品工业中是个问题，因为它们能够形成内生孢子并在加工条件下存活。因此，它们在食品中的萌发对食品的保质期和安全性都构成威胁。本文报道了超临界流体二氧化碳（SF-CO）在食品中灭活形成芽孢微生物方面的应用现状。与高静水压和热力过程不同，高静水压和热力过程难以使芽孢失活和破坏，而且即使能做到，也会对食品的营养和品质特性产生不利影响。这项技术对于灭活芽孢和保持食品的结构及营养特性是可行的。灭活机制可分为：（1）由于细胞壁、芽孢衣和皮层破裂以及细胞膜破坏而导致细胞内容物释放；（2）与渗透和穿透的SF-CO相互作用导致蛋白质降解；（3）酶活性失活。研究发现，超声（另一种非热技术）或添加水、过氧化氢、乙醇等共溶剂或抗菌肽的协同效应大大增强了芽孢的灭活效果。这项工作整合了已发表的关于芽孢灭活机制的观点，并将有助于为进一步研究SF-CO在食品杀菌中的应用提供参考。
