低压静电场处理对带鱼微冻贮藏期间品质变化影响

Effect of Low Voltage Electrostatic Field(LVEF)Treatment on the Quality Changes of Trichiurus lepturus during Micro-frozen Storage

为研究低压静电场技术(Low voltage electrostatic field,LVEF)对带鱼微冻贮藏保鲜过程中品质变化影响,本文以新鲜舟山带鱼为实验原料,由冷冻曲线法得其冰点后予以分组。其中,实验组在-4℃条件下进行低压静电场(3000 V、50 Hz)处理,以未做电场处理样品为对照组。期间,分别进行两组样品的pH、总挥发性盐基氮(TVB-N)、硫代巴比妥酸值(TBA)、菌落总数(TVC)与K值测定,结合苏木精-伊红(Hematoxylin&Eosin,H&E)染色与扫描电镜(SEM)分析,综合评价LVEF协同微冻对带鱼贮藏期间品质变化的影响。结果表明:对照组样品在第21 d时的TVB-N值为29.81 mg/100 g,接近不可食状态;第28 d时的TBA值为1.78 mg MDA/100 g,TVC值超过腐败限值,K值增至88.71%,背肌肌肉纤维变形收缩,产生严重扭曲折叠,鱼体腐败严重;而处理组样品在第28 d时的TVB-N、TBA与TVC值均低于对照组,pH变化幅度不明显,K值为63.17%,细胞间结构完整大小均匀,仅有轻微组织损伤,保鲜效果好。因此,LVEF技术能有效缓解带鱼微冻贮藏过程中的品质劣变,与对照组相比,其可延长微冻带鱼货架期7 d。

To study the influence of low voltage electrostatic field on the quality change of Trichiurus lepturus during its micro-frozen storage and preservation process,fresh Trichiurus lepturus of Zhoushan was used as experimental raw material and divided into groups after getting freezing point by freezing curve method in this article.Among them,the experimental group was treated by low-voltage electrostatic field(3000 V,50 Hz)under the temperature of four degrees below zero while the control group was not treated with electric field.During the experimental time,the pH value,TVB-N,TBA,TVC and K value of the two groups were measured.Combined with Hematoxylin&Eosin,H&E dying and SEM analysis,a comprehensive evaluation of the influence of LVEF and micro-frozen on the effect of the Trichiurus lepturus during the storage time were discussed.The results showed that the TVB-N value of the control group was 29.81 mg/100 g on the twenty-first day,which was near to inedible statues.On the twenty-eighth day,the TBA value was 1.78 mg MDA/100 g,the TVC value exceeded the corruption limitation,and the K value increased to 88.71%.The back muscle fibers were deformed and contracted,resulting in severe distortion and folding,and the Trichiurus lepturus body was severely corrupted;the TVB-N,TBA and TVC value of samples in the experimental groups were lower than the control groups on the twenty-eighth day,the pH value change was not obvious,the K value was 63.17%,the size of intercellular structure was uniform,only slight tissue damage existed,so it had a good preservation effect.Therefore,LVEF technology can effectively alleviate the quality deterioration of Trichiurus lepturus in micro-frozen storage process.Compared with control group,it can extend 7 days of micro-frozen Trichiurus lepturus on the shelf period.