牛至精油对荧光假单胞菌的抑制作用及其对冷藏三文鱼品质的影响  

Inhibitory Effect of Oregano Essential Oil against Spoilage Microorganism Pseudomonas fluorescens and Its Influence on Quality Changes during Chilled Storage of Salmon

作　　者：杨胜平[1,2] 章缜 程颖 钱韻芳[1,2] 谢晶[1,2] YANG Shengping;ZHANG Zhen;CHENG Ying;QIAN Yunfang;XIE Jing(College of Food Science and Technology,Shanghai Ocean University,Shanghai 201306,China;Shanghai Engineering Research Center of Aquatic Product Processing and Preservation,Shanghai 201306,China)

机构地区：[1]上海海洋大学食品学院,上海201306 [2]上海水产品加工及贮藏工程技术研究中心,上海201306

出　　处：《食品科学》2020年第1期215-222,共8页Food Science

基　　金：国家自然科学基金面上项目（31571914）;国家自然科学基金青年科学基金项目（31501551）;上海水产品加工及贮藏工程技术研究中心能力提升项目（19DZ2284000）;博士科研启动基金项目（A2-2006-00-200360）;上海海洋大学科技发展专项

摘　　要：为研究牛至精油对三文鱼特定腐败菌之一荧光假单胞菌的抑制效果及其对冷藏三文鱼品质的影响,分别测定了牛至精油对荧光假单胞菌的最小抑菌浓度(minimum inhibitory concentration,MIC)、细菌生长曲线、细菌细胞膜流动性、细菌培养液电导率、碱性磷酸酶活力并观察细胞微观结构,分析了牛至精油浸泡处理对三文鱼冷藏过程中对感官得分、菌落总数、总挥发性盐基氮含量、生物胺含量及水分迁移情况,并以未加牛至精油处理的样品为对照。结果表明:牛至精油对荧光假单胞菌的MIC为0.062 5%(体积分数),与对照组相比,MIC牛至精油处理组荧光假单胞菌培养液电导率上升,细菌失去原有的细胞形态,细胞膜的荧光强度更高,说明牛至精油处理破坏了荧光假单胞菌细胞膜,使细胞内容物外渗,降低了荧光假单胞菌对细胞膜流动性的调节能力。同时研究了MIC牛至精油对接种有荧光假单胞菌的冷藏三文鱼的保鲜效果,结果显示,贮藏末期(12 d)牛至精油处理组菌落总数较对照组降低1.34(lg(CFU/g)),总挥发性盐基氮含量较对照组降低7.48 mg/100 g,腐胺和尸胺含量较对照组分别降低48.5%和33.5%,而且牛至精油能抑制不易流动水向自由水转变,对抑制假单胞菌生长和保持三文鱼品质具有良好效果。This study was intended to evaluate the effect of oregano essential oil against Pseudomonas fluorescens and the quality of salmon during cold storage. The minimal inhibitory concentration(MIC) of oregano essential oil against P. fluorescens was determined in vitro, as well as its effect on the growth curve, membrane fluidity, microstructure, electrical conductivity and alkaline phosphatase(AKPase) activity of P. fluorescens. Salmon fillets were inoculated with P. fluorescens, dipped in oregano essential oil and then stored at 4 ℃. Those not treated with oregano essential oil were served as control. Changes in the quality indicators including sensory quality, bacterial count, total volatile basic nitrogen(TVB-N) content, biogenic amines and T2 parameters of nuclear magnetic resonance were studied during storage. The results showed that the minimum inhibitory concentration(MIC) of oregano essential oil against P. fluorescens was 0.062 5%(V/V). The bacterial cells treated with oregano essential oil at MIC exhibited increased electric conductivity and lose their original morphology. The fluorescence intensity of the cell membrane of P. fluorescens treated by oregano essential oil was higher than that of the control, indicating that oregano essential damaged the cell membrane during cold adaptation leading to the leakage of intracellular compounds and consequently reduced ability of P. fluorescens to regulate membrane fluidity. At the end(day 12) of storage, the total bacterial count of the treated sample decreased by 1.34(lg(CFU/g)), the TVB-N content by 7.48 mg/100 g, and the contents of putrescine and cadaverine by 48.5% and 33.5%, respectively as compared to the control. In addition, oregano essential oil inhibited transformation of immobilized water to free water, thereby inhibiting the growth of P. fluorescens and maintaining the quality of salmon fillets.

关 键 词：牛至精油 荧光假单胞菌 冷藏 三文鱼 保鲜 

分 类 号：TS254.4[轻工技术与工程—水产品加工及贮藏工程]