Dept of Food Science, Nutrition and Health Promotion, Mississippi State Univ, Mississippi State, MS 39762, USA.
J Food Sci. 2012 Sep;77(9):M516-22. doi: 10.1111/j.1750-3841.2012.02859.x. Epub 2012 Aug 17.
The antimicrobial activity of various essential oils and carvacrol was determined on fresh raw catfish fillets against a 4-strain Listeria monocytogenes mixture representing serotypes 1/2b, 3b, 4b, and 4c that were predominantly isolated from catfish processing environments. Thyme oil, oregano oil and carvacrol exhibited concentration and time dependent responses in broth against L. monocytogenes; for example 0.5% concentrations resulted in 4 log CFU/mL reduction within 30 min whereas 0.1% concentrations required more than 24 h for the same level of reduction. Lemon, orange, and tangerine oils, at 0.5% showed listeriostatic effect in which 4 log CFU/mL of the initial L. monocytogenes load was unchanged at 4 °C in 10 d whereas 1% concentrations were listericidal in a time dependent manner. Apart from carvacrol, efficacy of tested essential oils in reducing L. monocytogenes and total microbial load from catfish fillet was very limited. Dipping treatment of catfish fillets in 2% carvacrol solution for 30 min at 4 °C reduced L. monocytogenes to an undetectable level from their initial load of 5 log CFU/g and reduced total microbial load from catfish fillets by approximately 5 log CFU/g. In sensory analysis trained panelist preferred control samples over 2% carvacrol treated samples implying potential limitation in applicability of carvacrol for fillet treatments.
各种精油和香芹酚的抗菌活性在新鲜生鲶鱼片上针对代表血清型 1/2b、3b、4b 和 4c 的 4 株李斯特菌混合物进行了测定，这些血清型主要从鲶鱼加工环境中分离出来。百里香精油、牛至油和香芹酚在肉汤中对李斯特菌表现出浓度和时间依赖性反应；例如，0.5%的浓度在 30 分钟内导致 4 对数 CFU/mL 的减少，而 0.1%的浓度则需要超过 24 小时才能达到相同的减少水平。柠檬、橙子和橘子油在 0.5%的浓度下表现出抑菌作用，即在 4°C 下 10 天内初始李斯特菌负荷的 4 对数 CFU/mL 不变，而 1%的浓度则以时间依赖性方式具有杀菌作用。除了香芹酚外，测试精油在减少鲶鱼片上李斯特菌和总微生物负荷方面的效果非常有限。将鲶鱼片在 4°C 下用 2%香芹酚溶液浸泡 30 分钟，可将李斯特菌从初始负荷 5 对数 CFU/g 降低至无法检测水平，并将鲶鱼片上的总微生物负荷降低约 5 对数 CFU/g。在感官分析中，经过培训的小组更喜欢对照样品而不是 2%香芹酚处理的样品，这意味着香芹酚在鱼片处理方面的适用性可能存在限制。
