Kazuya Morimatsu
Department of Food Production Science, Graduate School of Agriculture, Ehime University, 3-5-7 Tarumi, Matsuyama 790-8566, Ehime, Japan.
Microorganisms. 2025 Jun 24;13(7):1469. doi: 10.3390/microorganisms13071469.
Medium-high-hydrostatic-pressure (MHHP) treatment can induce the spore to germinate via activating the germination receptor, subsequently resulting in the loss of the heat resistance of the spore and finally killing the germinated spore, although the ungerminated spore, even after MHHP treatment, can survive. This study aims to clarify the pasteurization effect of the combination of MHHP treatment with post-/pre-heating treatment on spores suspended in soy milk as a food model. Regarding the results, the D value, as a known heat resistance indicator of the MHHP-treated spore, decreased in comparison with the untreated spore. However, the activation energies required for killing both the untreated and the MHHP-treated spores were equivalent, which indicated that the heat conductivity of the ungerminated spores might be increased by MHHP treatment. When the spore was subjected to pre-heating treatment and subsequently to MHHP treatment, the pasteurization effect of MHHP treatment differed with the pre-heating temperature. Pre-heating treatment at 80 °C could promote pasteurization, while that at 90-100 °C could suppress it, which might be caused by the heat activation/inactivation of germination receptors. From these results, the presence of post-/pre-heat treatment could be an important factor for the pasteurization of spores via MHHP treatment.
中高静水压（MHHP）处理可通过激活萌发受体诱导孢子萌发，随后导致孢子耐热性丧失并最终杀死已萌发的孢子，尽管未萌发的孢子即使经过MHHP处理仍能存活。本研究旨在阐明MHHP处理与后/预热处理相结合对悬浮在豆奶中的孢子作为食品模型的巴氏杀菌效果。关于结果，作为MHHP处理孢子已知耐热性指标的D值与未处理的孢子相比有所降低。然而，杀死未处理和MHHP处理孢子所需的活化能相当，这表明未萌发孢子的热导率可能因MHHP处理而增加。当孢子先进行预热处理然后进行MHHP处理时，MHHP处理的巴氏杀菌效果因预热温度而异。80℃的预热处理可促进巴氏杀菌，而90-100℃的预热处理则会抑制巴氏杀菌，这可能是由萌发受体的热激活/失活引起的。从这些结果来看，后/预热处理的存在可能是通过MHHP处理对孢子进行巴氏杀菌的一个重要因素。
