This study aimed to assess the effects of edible gelatin nanogel coating containing thymol and nisin on the inhibition of microbial flora and inoculated Listeria monocytogenes in fish fillets during a 12-day storage period at the temperature of 4°C. Data were collected and analysed on several factors of microbiological change, including total viable count, total psychrophilic count, lactic acid bacteria and hydrogen sulphide-producing bacteria count, and the inhibitory effects of the coating on inoculated Listeria monocytogenes were determined during 3-day intervals. The highest reduction rate of total viable bacteria (0.95 log CFU/g), total psychrophilic (0.92 log CFU/g), Hydrogen sulfide producing bacteria (0.66 log CFU/g), lactic acid bacteria (0.95 log CFU/g) and L. monocytogenes count (0.65 log CFU/g) were observed in gelatin nanogel containing thymol and nisin in comparison with control samples. Furthermore, the separate use of these compounds led to the significant growth inhibition of the bacteria compared with the control. Therefore, it was concluded that the gelatin nanogel coating without an antimicrobial agent could not be effective in bacterial growth control, and the added thymol and nisin would be beneficial in the preservation of foods such as fish and its products.

中文翻译：

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含有百里酚和乳酸链球菌肽的明胶纳米凝胶涂层对虹鳟鱼片和接种单核细胞增生李斯特菌微生物品质的影响

本研究旨在评估含有百里酚和乳酸链球菌肽的可食用明胶纳米凝胶涂层在 4°C 温度下 12 天储存期间对抑制微生物菌群和接种鱼片中的单核细胞增生李斯特菌的影响。收集和分析微生物变化的几个因素的数据，包括总活菌数、总嗜冷菌数、乳酸菌和产生硫化氢的菌数，并在 3 天的间隔内确定涂层对接种的单核细胞增生李斯特菌的抑制作用. 总活菌 (0.95 log CFU/g)、总嗜冷菌 (0.92 log CFU/g)、产硫化氢菌 (0.66 log CFU/g)、乳酸菌 (0.95 log CFU/g) 和与对照样品相比，在含有百里酚和乳酸链球菌肽的明胶纳米凝胶中观察到单核细胞增生李斯特菌计数 (0.65 log CFU/g)。此外，与对照相比，这些化合物的单独使用导致细菌的显着生长抑制。因此得出结论，不含抗菌剂的明胶纳米凝胶涂层不能有效控制细菌生长，添加百里酚和乳链菌肽将有利于鱼类及其制品等食品的保鲜。