鲢鱼片在微冻贮藏中品质、ATP关联物及关联酶活性变化规律研究

Changes of quality,ATP-related compounds and enzyme activities in silver carp(Hypophthalmichthys molitrix)fillets during partial freezing

为更好地了解鲢鱼(Hypophthalmichthys molitrix)在微冻贮藏过程中的相关品质变化,对微冻条件(-3℃)下生鲜鲢鱼片品质指标,ATP关联产物及ATP关联酶活性的变化规律进行试验研究。结果表明:微冻条件下,挥发性盐基氮的质量分数呈现不断上升的趋势,但在30d贮藏时间内未超过国家规定的二级新鲜度标准(20mg/100g);随着贮藏时间的延长,菌落总数的对数值不断增加;而感官分值、盐溶性蛋白质质量分数、Ca2+-ATPase活性、质构特性(弹性、硬度、内聚性)等呈现下降趋势。此外,三磷酸腺苷(ATP)、肌苷酸(IMP)含量随贮藏时间的延长显著下降(P<0.05);次黄嘌呤核苷(HxR)含量先升高后降低并在第9天时达到最大值;次黄嘌呤(Hx)含量不断增加。相关性分析表明,酸性磷酸水解酶(ACP)和腺苷脱氨酶(ADA)的活性变化不能表征ATP关联物含量的变化情况。

In order to obtain the quality changes of silver carp（Hypophthalmichthys molitrix）,quality indicators,ATPrelated compounds and enzyme activities of silver carp were measured during partial freezing.The results indicated that：During partial freezing,mass fraction of total volatile base nitrogen（w（TVB-N））increased but didn＇t reach the limitation on country＇s regulation of 20mg/100g;With the increasing of storage time,logarithmic value of total aerobic counts（lg[TAC/（CFU/g）]）went up,while sensory scores,salt soluble protein content,Ca^2＋-ATPase activity,texture properties decreased;ATP-related compounds and enzyme activities,content of ATP、IMP came down,Hx rose up with time and HxR increased at first and then decreased,and reached peak on nine days of storage.In conclusion,changes in acid phosphatase（ACP）and AMP-deaminase（ADA）activities cannot perfectly represent the variations on ATP-related compounds.