UMT 08.3 PHYSI'Opt, Z.A. de Creac'h Gwen, F-29196 Quimper Cedex, France.
Food Microbiol. 2012 May;30(1):29-36. doi: 10.1016/j.fm.2011.09.017. Epub 2011 Oct 8.
Although sporulation environmental factors are known to impact on Bacillus spore heat resistance, they are not integrated into predictive models used to calculate the efficiency of heating processes. This work reports the influence of temperature and pH encountered during sporulation on heat resistance of Bacillus weihenstephanensis KBAB4 and Bacillus licheniformis AD978 spores. A decrease in heat resistance (δ) was observed for spores produced either at low temperature, at high temperature or at acidic pH. Sporulation temperature and pH maximizing the spore heat resistance were identified. Heat sensitivity (z) was not modified whatever the sporulation environmental factors were. A resistance secondary model inspired by the Rosso model was proposed. Sporulation temperatures and pHs minimizing or maximizing the spore heat resistance (T(min(R)), T(opt(R)), T(max(R)), pH(min(R)) and pH(opt(R))) were estimated. The goodness of the model fit was assessed for both studied strains and literature data. The estimation of the sporulation temperature and pH maximizing the spore heat resistance is of great interest to produce spores assessing the spore inactivation in the heating processes applied by the food industry.
尽管已知孢子形成环境因素会影响芽孢杆菌孢子的耐热性，但它们并未整合到用于计算加热过程效率的预测模型中。本工作报告了在芽孢杆菌 weihenstephanensis KBAB4 和地衣芽孢杆菌 AD978 孢子形成过程中遇到的温度和 pH 值对其耐热性的影响。在低温、高温或酸性 pH 值下产生的孢子的耐热性降低（δ）。确定了使孢子耐热性最大化的最佳孢子形成温度和 pH 值。无论孢子形成环境因素如何，热敏感性（z）都不会改变。提出了一个受 Rosso 模型启发的抗性二次模型。估计了使孢子耐热性最小化或最大化的孢子形成温度和 pH 值（T(min(R)), T(opt(R)), T(max(R)), pH(min(R))和 pH(opt(R)))。对两种研究菌株和文献数据进行了模型拟合优度评估。估计使孢子耐热性最大化的孢子形成温度和 pH 值对于在食品工业中应用的加热过程中评估孢子失活非常重要。
