二氧化氯对鲳鱼微冻贮藏品质的影响

用二氧化氯（ClO2）处理鲳鱼块后进行微冻（－3 ℃）贮藏，测定贮藏期间鱼肉的菌落总数、菌相、总挥 发性盐基氮（total volatile basis nitrogen，TVB-N）含量、K值、pH值及肌原纤维储能模量（G’）的变化，考察ClO2 处理对鲳鱼块微冻贮藏品质的影响。结果表明：30 μg/mL ClO2处理（料液比1∶20（m/V），浸泡10 min）可以使鱼 块的初始菌落总数降低约2 （lg（CFU/g））。贮藏过程中，处理组鱼块的菌落总数始终低于对照组，但贮藏初期 处理组鱼块的细菌生长速率明显高于对照组；2 组鱼块的优势腐败菌均由初期的希瓦氏菌属过渡到末期的假单胞菌 属；根据鱼肉的TVB-N含量，对照组于贮藏第20天变为二级鲜度，而处理组在贮藏的32 d内一直处于一级鲜度； ClO2处理使鱼肉初始pH值下降0.52，贮藏期间处理组鱼肉的pH值始终低于对照组约0.2～0.4；贮藏期间2 组鱼肉 的K值差别不大，对照组和处理组分别于贮藏12、16 d达到40%；处理组鱼肉的肌原纤维蛋白G’峰值始终高于对照 组。上述结果表明，ClO2处理结合微冻贮藏能够有效提升鲳鱼块鲜度、延长其货架期。

Effect of Chlorine Dioxide on Pomfret Quality during Superchilled Storage

In this paper, pomfret fillet was pretreated with ClO2 and subsequently stored at superchilled temperature (?3 ℃). During storage, meat quality was evaluated by total plate count (TPC), microflora, total volatile basic nitrogen (TVB-N) content, K value, pH value and rheological property (storage modulus) of myofibrillar protein. Results showed that treatment with 30 μg/mL ClO2 (1:20 of solid-to-liquid ratio (m/V), soaking for 10 min) reduced the initial TPC by 2 (lg(CFU/g)). The ClO2 group demonstrated lower TPC than the control throughout the storage period. But during the initial stage, the growth rate of residual bacteria in the ClO2 group was higher than that of the control group. For both groups, the dominant spoilage bacteria were Shewanella and Pseudomonas at the initial and final stages, respectively. According to the TVB-N content, the freshness of the control decreased to second grade after 20 days of storage, whereas that of the ClO2 group remained the same (first grade) throughout the 32-day storage period. ClO2 treatment lowered the pH of fresh fillet by 0.52 and the pH value of the ClO2 group was always 0.2–0.4 lower than that of the control. The K values of the control and ClO2 groups reached 40% on days 12 and 16, respectively, with no significant difference being observed between the two groups during storage. The peak value of storage modulus of myofibrillar protein in the ClO2 group was higher than that of the control during the whole storage period. The above results suggested that the use of ClO2 pretreatment in conjunction with superchilled storage could maintain the freshness and extend the shelf-life of pomfret fillet.