Studies On The Refrigeration Preservation Technology Of Jack Mackerel (Trachurus Murphyi)

With the rapid development of China’s distant ocean fisheries, aquatic product storage and preservation technology research is particularly important. This paper studied on the Jack mackerel (Trachurus murphyi) on board and trimethylamine (TMA), total volatile basic nitrogen (TVB-N) as indicators. Conclusion on the effects of different slaughter methods, the initial center temperature, cold seawater, chilling speed, different rigor mortis development treatment on the quality of Chilean jack mackerel during storage at4℃can optimize pre-treatment of production and processing of Jack mackerel.1. Changes in storage quality of Jack mackerel at4℃temperature for6days treated by different slaughter methods were studied. Higher pH values were found in fishes killed by AI than in those killed by AA and SH at day0. TMA had sharp increased during storage in all treatments and AI group had lower increase (p<0.05) than AA and SH groups. TVB-N increased with the storage time and killed by AI delayed accumulation of TVB-N significantly (P<0.05) during subsequent refrigerate storage. In addition, variations in2-thiobarbituric acid reactive substances (TBA) were significant differences (p<0.05) in all treatment showed a decrease in TBA in AI group. Results indicated that asphyxia in ice water to death maintains the quality of Jack mackerel during storage at4℃.2. Changes in storage quality of Chilean jack mackerel with different initial central temperature at4℃temperature for6days were studied. Three different initial central temperature including0℃(A group),3℃(B group) and6℃(C group), and pH values, TVB-N, TMA, TBA and sensory assessment for whole jack mackerel were determined. The results indicated that pH, TVB-N, TMA and TBA values increased as refrigerated storage progressed and we found these values of fishes in C group were significant higher than those in A and B group (p<0.05). In addition, sensory scores showed significantly (p<0.05) lower in C group than A and B groups. On the basis of present results, it is highly recommended that lower initial central temperature of fish could maintain better quality of Chilean jack mackerel during refrigerated storage.3. Changes in storage quality of Chilean jack mackerel (Trachurus murphyi) with different cold seawater pretreatment at4℃temperature for6days were studied. Two different treated time including6h (T1group),12h (T2group), and pH values, TVB-N, TMA, TBA and sensory assessment for whole jack mackerel were determined. The results indicated that pH, TVB-N, TMA and TBA values increased as refrigerated storage progressed and we found these values of fishes in T1group were significant higher than T2group (p<0.05). In addition, sensory scores showed significantly (p<0.05) lower in T2group than T1group. On the basis of present results, it is highly recommended that longer treatment with cold seawater of fish could maintain better quality of Chilean jack mackerel during refrigerated storage.4. The effects of chilling speed with different temperature on the quality of Chilean jack mackerel was studied. Two different treated time including-18℃,2℃and without pre-chilling treatment as control group and pH values, TVB-N, TMA, TBA and sensory assessment for whole jack mackerel were determined. The results indicated that pH, TVB-N, TMA and TBA values increased as refrigerated storage progressed and we found these values of fishes in control group were significant higher than the other groups(p<0.05). We can conclude that the faster chilling speed could maintain better quality of fish during refrigerated storage.5. The effects of different rigor mortis development on the quality of Chilean jack mackerel was studied. Full rigor as experiment group and pre-rigor as control group. And pH values, TVB-N, TMA, TBA and sensory assessment for whole jack mackerel were determined. The results indicated that pH, TVB-N, TMA and TBA values increased as refrigerated storage progressed and we found these values of fishes in experiment group were significant higher than control groups(p<0.05). From the data, we can conclude that the lower rigor mortis could maintain better quality of fish during refrigerated storage at4±1℃.