Jiangnan Univ., 1800 Lihu Ave., Wuxi, Jiangsu 214122, China.
J Food Sci. 2013 Aug;78(8):M1195-200. doi: 10.1111/1750-3841.12180.
Foodborne pathogens such as Listeria monocytogenes could pose a health risk on frozen ready-to-eat (RTE) shrimp as the pathogen could grow following thawing. In this study, antimicrobial-coating treatments alone, or in combination with cryogenic freezing, were evaluated for their ability to inhibit the growth of Listeria innocua, a surrogate for L. monocytogenes, on RTE shrimp. Cooked RTE shrimp were inoculated with L. innocua at 3 population levels and treated with coating solutions consisting of chitosan, allyl isothiocyanate (AIT), or lauric arginate ester (LAE). The treated shrimp were then stored at -18 °C for 6 d before being thawed at 4, 10, or 22 °C for either 24 or 48 h. Results revealed that antimicrobial coatings achieved approximately 5.5 to 1 log CFU/g reduction of L. innocua on RTE shrimp after the treatments, depending on the inoculated population levels. The coating-treated shrimp samples had significantly (P < 0.05) less L. innocua than controls at each thawing temperature and time. Cryogenic freezing in combination with coating treatments did not achieve synergistic effects against L. innocua. Antimicrobial coatings can help to improve product safety by reducing Listeria on RTE shrimp.
食源性致病菌，如单增李斯特菌，可能对冷冻即食（RTE）虾构成健康风险，因为该病原体在解冻后可能会生长。在本研究中，单独或结合低温冷冻评估了抗菌涂层处理对抑制 RTE 虾中无毒李斯特菌（Listeria innocua，单增李斯特菌的替代品）生长的能力。将烹饪后的 RTE 虾用 3 种不同的菌液浓度接种无毒李斯特菌，并使用壳聚糖、丙烯基异硫氰酸酯（AIT）或月桂精氨酸酯（LAE）的涂层溶液进行处理。处理后的虾在-18°C 下储存 6 天，然后在 4、10 或 22°C 下解冻 24 或 48 小时。结果表明，根据接种的菌液浓度，抗菌涂层处理后可使 RTE 虾上的无毒李斯特菌减少约 5.5 至 1 个对数 CFU/g。在每个解冻温度和时间点，经涂层处理的虾样中的无毒李斯特菌均显著低于对照组（P < 0.05）。低温冷冻与涂层处理结合并未对无毒李斯特菌产生协同作用。抗菌涂层可以通过减少 RTE 虾中的李斯特菌来帮助提高产品安全性。
