Devlieghere F, Debevere J, Van Impe J
University of Gent, Department of Food Technology and Nutrition, Belgium.
Int J Food Microbiol. 1998 Jun 16;41(3):231-8. doi: 10.1016/s0168-1605(98)00052-x.
Carbon dioxide is known to be the active gas in modified atmosphere packaging. However, only the dissolved part of the CO2 will be active in the inhibition of microorganisms. When the effect of a modified atmosphere on the growth of microorganisms is modeled, the amount of dissolved CO2 should be the parameter to evaluate the effect of CO2 in modified atmospheres. Lactobacillus sake was isolated from cooked ham, identified and was chosen as a representative organism for the spoilage of modified atmosphere packed cooked meat products. In a first step a suitable liquid simulation medium for cooked meat products was selected. The growth rate of L. sake was significantly higher in modified MRS than in cooked ham, while no significant difference was observed between the growth parameters of L. sake in modified BHI and in cooked ham. Careful evaluation of the applied simulation medium was shown to be essential before application to the development of predictive models for nutrient demanding microorganisms such as lactic acid bacteria. In a second step, the influence of dissolved CO2 and the storage temperature on the growth parameters of L. sake was modeled. Temperature was shown to have a major effect on the growth rate and lag phase of L. sake. Carbon dioxide negatively influenced the growth rate of L. sake. A negative, linear relationship was observed between the growth rate and the amount of dissolved carbon dioxide. Carbon dioxide was shown, however, to have no significant effect on the lag phase of L. sake. A significant interaction term between temperature and dissolved CO2 on the growth rate of L. sake was established.
众所周知，二氧化碳是气调包装中的活性气体。然而，只有溶解的那部分二氧化碳才会在抑制微生物方面发挥作用。在对气调环境对微生物生长的影响进行建模时，溶解二氧化碳的量应作为评估气调环境中二氧化碳效果的参数。清酒乳杆菌是从熟火腿中分离出来的，经过鉴定后被选为气调包装熟肉制品腐败的代表性微生物。第一步，选择了一种适合熟肉制品的液体模拟培养基。清酒乳杆菌在改良MRS培养基中的生长速率显著高于在熟火腿中的生长速率，而清酒乳杆菌在改良BHI培养基和熟火腿中的生长参数之间未观察到显著差异。在将其应用于开发针对乳酸菌等营养需求型微生物的预测模型之前，仔细评估所应用的模拟培养基至关重要。第二步，对溶解二氧化碳和储存温度对清酒乳杆菌生长参数的影响进行建模。结果表明，温度对清酒乳杆菌的生长速率和滞后期有主要影响。二氧化碳对清酒乳杆菌的生长速率有负面影响。在生长速率和溶解二氧化碳量之间观察到负的线性关系。然而，二氧化碳对清酒乳杆菌的滞后期没有显著影响。建立了温度和溶解二氧化碳对清酒乳杆菌生长速率的显著交互项。
