蒸煮贻贝冰温贮藏保鲜剂的筛选、优化及评价

Screening,optimization and evaluation of ice temperature preservation agents for steamed mussels

目的筛选用于改善冰温贮藏蒸煮贻贝品质、延长蒸煮贻贝保质期的生物保鲜剂,对复合保鲜剂的配方及保鲜工艺进行优化,并评价其保鲜效果。方法通过测定保鲜剂作用于贻贝优势腐败菌的抑菌圈大小,筛选出抑菌效果较强的保鲜剂,运用响应面法优化复合保鲜剂配方,采用肉汤稀释法测定最小抑菌浓度(minimum inhibitory concentration,MIC);利用正交实验确定复合保鲜剂用于蒸煮贻贝保鲜的最佳工艺;通过测定蒸煮贻贝冰温贮藏8 d后的感官评分、pH、挥发性盐基氮(total volatile basic nitrogen,TVB-N)含量、菌落总数、汁液流失率来评价复合保鲜剂的效果。结果筛选出的3种保鲜剂分别为溶酶菌、乳酸链球菌素和丁香酚,复合保鲜剂对枯草芽孢杆菌和假单胞菌的MIC分别为16、8μg/mL,复合保鲜剂的优化配方(质量分数)为溶菌酶4%、乳酸链球菌素2%和丁香酚0.75%,最佳保鲜工艺为保鲜剂溶液pH 5.5、料液比1:2.5(m:V)、浸泡时间60 min,采用优化的配方和工艺用于蒸煮贻贝的冰温贮藏,贻贝品质的综合评分为空白样品的2倍。结论复合保鲜剂可以有效改善蒸煮贻贝在冰温贮藏条件下的鲜度和品质,延长保质期,从而拓宽物流范围。

Objective To screen the biological preservatives used to improve the quality of steamed mussels stored in ice temperature and prolong the shelf life of steamed mussels,optimize the formulation and preservation technology of the compound preservatives,and evaluate the preservation effect.Methods By measuring the bacteriostatic circle size of the preservative acting on the dominant spoilage bacteria of mussel,the preservative with strong bacteriostatic effect was selected,the formulation of the compound preservative was optimized by response surface methodology,and the minimum inhibitory concentration(MIC)was determined by broth dilution method;orthogonal experiment was used to determine the best technology of compound preservative for cooking mussel;the effect of the compound preservative was evaluated by measuring the sensory score,pH,total volatile basic nitrogen(TVB-N)content,total number of colonies,and juice loss rate of steamed mussels after 8 d of ice temperature storage.Results The 3 selected preservatives were lysozyme,nisin and eugenol,and the MIC of the compound preservative against Bacillus subtilis and Pseudomonas was 16,8μg/mL,the optimal formulation(mass fraction)of the composite preservative was lysozyme 4%,nisin 2%and eugenol 0.75%.The optimal preservative process was the preservative solution pH 5.5,the ratio of material to liquid 1:2.5(m:V),and the soaking time was 60 min.The optimized formulation and process were used for the ice temperature storage of steamed mussels.The comprehensive score of mussel quality was twice that of the blank sample.Conclusion The compound preservative can effectively improve the freshness and quality of steamed mussels under ice temperature storage,extend the shelf life,and expand the logistics scope.