臭氧水杀菌对冰温贮藏牡蛎新鲜度和品质的影响

Effect of Ozone Water Sterilization on Freshness and Quality of Oysters during Ice Temperature Storage

为明确臭氧水杀菌处理对生食水产品新鲜度和品质的影响,以新鲜牡蛎为研究对象,分析不同质量浓度(2,4,6,8mg/L和10 mg/L)臭氧水作用不同时间(1,2,3,4 min和5 min)后,冰温贮藏牡蛎pH值、色差、感官指标、挥发性盐基氮(TVB-N)值和挥发性化合物等的变化情况。结果表明,质量浓度为4 mg/L的臭氧水作用2 min后,牡蛎肉的菌落总数(TVC)降至最低(3.58 CFU/g)。随着贮藏时间的增加,未处理组在第6天后TVB-N值>10 mg/(100 g),且增长速度显著大于处理组(P<0.05)。感官评定中,未被臭氧处理组在第7天感官评分低于8分,为不合格,而4 mg/L以上的臭氧水处理组,在第8天感官评分仍为合格,且未处理组牡蛎感官评分下降速度显著大于处理组(P<0.05)。各组牡蛎肉pH值在冷藏期间呈先下降后上升趋势,其中未处理组pH值由6.60下降至6.34后上升至6.86,上升趋势明显。冰藏期间,牡蛎肉的L^(*)值逐渐下降,a^(*)和b^(*)上升,与对照组相比,臭氧水杀菌处理保持了牡蛎肉的亮度。臭氧处理后牡蛎肉挥发性主成分贡献率为90.057%,能够反映牡蛎贮藏期间的主要特征信息及总体风味轮廓。结论:臭氧质量浓度4 mg/L为牡蛎适合的臭氧水杀菌浓度(作用时间2 min),且对风味无影响。臭氧处理是适用生食水产品加工的一种良好的非热杀菌处理方式。

In order to determine the effects of ozonated water sterilization treatment on the freshness and quality of raw aquatic products,the fresh oyster was used as the study object,the changes of in pH value,color difference,sensory index,volatile nitrogen(TVB-N)value and volatile compounds in oysters stored at ice temperature were studied after different concentrations(2,4,6,8,10 mg/L)of ozone water treatment for different times(1,2,3,4,5 min).The results showed that the total colony count(TVC)of oyster meat decreased to a minimum of 3.58 CFU/g after treatment with 4 mg/L for 2 min.With the increase of storage time,the TVB-N value of the untreated group reached more than 10 mg/(100 g)after 6 days of storage,and the growth rate was significantly higher than that of the treated group(P<0.05).In the sensory assessment,the sensory score of the untreated group was lower than 8 points on the 7th day,which was considered unqualified,while the sensory score of the ozone-treated group was still qualified on the 8th day,and the sensory score of the untreated group decreased significantly faster than that of the treated group(P<0.05).The pH value of oyster meat in each group decreased first and then increased during the storage period,and the pH value in the untreated group decreased from 6.60 to 6.34 and then increased to 6.86,showing an obvious upward trend.During ice temperature storage,the L^(*)value of oyster meat gradually decreased,and a^(*)and b^(*)increased.Compared with the control group,the brightness of oyster meat was maintained by ozone water sterilization treatment.The contribution rate of volatile principal components of oyster meat after ozone treatment was 90.057%,which could reflect the main characteristic information and overall flavor profile of oyster during storage.Conclusion:Ozone concentration of 4 mg/L was suitable concentration of oyster(action time was 2 min),and has no effect on flavor.Ozone treatment is a good non-thermal sterilization treatment for raw aquatic products.