ABSTRACT

The sensitivity of Paenibacillus sp. and Terribacillus aidingensis spores to combined action of HP, nisin and moderate heating were investigated for the first time. The results showed that the effect of HP on spores varies with pressure level, treatment temperature, spore species and presence of nisin. T. aidingensis spores were more resistant than Paenibacillus sp., whatever the treatment applied. The inactivation rates of both spore species did not exceed 2.7log (CFU/mL) after HP treatment at 600 MPa/50°C/10 min. However, a high synergistic effect of nisin and HP was observed after a treatment at 500 MPa/10 min/50°C with addition of nisin during HP and into the recovery medium, leading to 6log (CFU/mL) and 4log (CFU/mL) reduction for Paenibacillus and Terribacillus spores, respectively. Finally, the fraction of germinated spores by HP was measured and the results showed that germination induction is not the only underlying mechanisms of nisin sensitization by HP.

摘要

类芽孢杆菌的敏感性。和Terribacillus aidingensis孢子HP，乳链菌肽和适度加热的组合作用进行了研究，第一次。结果表明，HP 对孢子的影响随压力水平、处理温度、孢子种类和乳链菌肽的存在而变化。T. aidingensis孢子比类芽孢杆菌更具抗性sp.，无论采用何种处理。在 600 MPa/50°C/10 分钟的高压处理后，两种孢子种类的灭活率均不超过 2.7log (CFU/mL)。然而，在 500 MPa/10 分钟/50°C 处理后观察到乳酸链球菌肽和 HP 的高度协同作用，在 HP 期间添加乳酸链球菌素并进入恢复培养基，导致​​ 6log (CFU/mL) 和 4log (CFU/ mL) 分别减少了类芽孢杆菌和特里杆菌孢子。最后，测量了 HP 萌发的孢子的比例，结果表明萌发诱导并不是 HP 对乳酸链球菌素致敏的唯一潜在机制。