Department of Food Science and Technology, International Campus of Excellence in the AgriFood Sector (CeiA3), University of Córdoba, C-1, 14014 Córdoba, Spain.
Department of Food Science and Technology, International Campus of Excellence in the AgriFood Sector (CeiA3), University of Córdoba, C-1, 14014 Córdoba, Spain.
Int J Food Microbiol. 2018 Apr 2;270:14-21. doi: 10.1016/j.ijfoodmicro.2018.02.005. Epub 2018 Feb 5.
Over the last couple of decades, several studies have evaluated growth dynamics of L. monocytogenes in lightly processed and ready-to-eat (RTE) fishery products mostly consumed in Nordic European countries. Other fish species from aquaculture production are of special interest since their relevant consumption patterns and added value in Mediterranean countries, such as sea bream and sea bass. In the present study, the growth of L. monocytogenes was evaluated in fish-based juice (FBJ) by means of optical density (OD) measurements in a temperature range 2-20 °C under different atmosphere conditions (i.e. reduced oxygen and aerobic). The Baranyi and Roberts model was used to estimate the maximum growth rate (μ) from the observed growth curves. The effect of storage temperature on μ was modelled using the Ratkowsky square root model. The developed models were validated using experimental growth data for L. monocytogenes in sea bream and sea bass fillets stored under static and dynamic temperature conditions. Overall, models developed in FBJ provided fail-safe predictions for L. monocytogenes growth. For the model generated under reduced oxygen conditions, bias and accuracy factor for growth rate predictions were 1.15 and 1.25, respectively, showing good performance to adequately predict L. monocytogenes growth in Mediterranean fish products. The present study provides validated predictive models for L. monocytogenes growth in Mediterranean fish species to be used in microbial risk assessment and shelf-life studies.
在过去的几十年里，已有多项研究评估了单核细胞增生李斯特菌在北欧国家消费的轻度加工和即食（RTE）渔业产品中的生长动态。来自水产养殖生产的其他鱼类品种也具有特殊的意义，因为它们在地中海国家的消费模式和附加值，如真鲷和鲈鱼。在本研究中，通过在 2-20°C 的温度范围内进行光学密度（OD）测量，评估了鱼汁（FBJ）中单核细胞增生李斯特菌的生长情况，在不同的大气条件（即低氧和需氧）下进行。采用 Baranyi 和 Roberts 模型从观察到的生长曲线中估计最大生长率（μ）。使用 Ratkowsky 平方根模型对储存温度对μ的影响进行建模。使用在静态和动态温度条件下储存的真鲷和鲈鱼鱼片中的单核细胞增生李斯特菌的实验生长数据验证所开发的模型。总体而言，在 FBJ 中开发的模型为单核细胞增生李斯特菌的生长提供了可靠的预测。对于在低氧条件下生成的模型，生长率预测的偏差和准确度因子分别为 1.15 和 1.25，表现出良好的性能，可以充分预测地中海鱼类产品中单核细胞增生李斯特菌的生长。本研究为地中海鱼类品种中单核细胞增生李斯特菌的生长提供了经过验证的预测模型，可用于微生物风险评估和保质期研究。
