流通过程对大目金枪鱼肉色稳定性与氧化性能的影响

目的:模拟大目金枪鱼的冷断链流通过程,分析流通期间的温度波动对大目金枪鱼肉色稳定性与氧化性能的影响。方法:以红度值、硫代巴比妥酸值(TBA)、肌红蛋白氧化态、高铁肌红蛋白还原酶、总酚浓度(TPC)、铁离子抗氧化能力(FRAP)等指标共同表征温度波动对其品质影响,并作指标相关性比较与动力学分析。结果:随着流通过程中的温度变化与流通时间的延长,冷链组样品在-55℃的色泽稳定性及氧化性能均几乎不发生变化,断链流通组样品由于温度波动而变化明显,且L2组样品变化最显著,其在流通末期红度值为2.43,鱼体脂肪氧化高达82.56%。氧合肌红蛋白伴随高铁肌红蛋白含量的增加而显著下降,酶活力受温度变化而对色泽产生影响,样品的红度值对温度变化反应敏感。所有样品在流通末期的TPC值均显著下降35%,FRAP值则分别降低16.15%和48.21%,64.78%(P<0.05)。相关性分析表明红度值可作为快速判断鱼肉品质变化的重要指标,该指标同TPC、FRAP、TBA值、肌红蛋白氧化态MMb相对含量与酶活等显著相关(P<0.05)。食品品质方程的动力学分析发现,大目金枪鱼的肉色稳定性与氧化性能指标随温度波动而变化显著。结论:L1与L2断链组样品在-55℃解冻流通48 h后明显下降,尤其L2组在销售(2℃)环节中为品质的劣变关键点。

The Effects Logistic Processes of on Color Stability and Oxidizing Capacity of Big-eye Tuna(Thunnus obesus)

Objective:The process of big-eye tuna in cold chain and logistic with temperature fluctuation were simulated respectively,the effects on color stability and oxidizing capacity of big-eye tuna during different logistic processes was researched.Methods:a^* value,TBA,myoglobin oxidation state,myoglobin reductase,total phenol concentration(TPC),ferric reducing antioxidant power(FRAP)were used to evaluate the quality of big-eye tuna during different logistic processes,the correlation and dynamic analysis among different parameters were also used for comparison.Results:The results showed that the color stability and oxidizing capacity are almost no change before 4℃in cold chain group(CK),but its changes significantly in logistic groups.a*value of L2 group is much more sensitive than other groups with the changing of temperature,the value was 2.43 and the value of lipid oxidation was reached 82.56%finally.Oxymyoglobin was declined significantly with the increase of myoglobin content,which the enzyme activity and color was affected by the change of temperature.TPC of all samples decreased 35%,FRAP of cold chain(CK)and logistic groups(L1L2)decreased 16.15%,48.21%and 64.78%respectively(P<0.05).Correlation analysis showed that a^* value can be used as an important index to evaluate the quality change of big-eye tuna,which was significantly related to TPC,FRAP,TBA,relative content of MMb and enzyme activity.From the results of dynamic analysis in food quality equation,it concluded that their variation degree was closely related with temperature fluctuation.Conclusion:The critical point of deterioration for big-eye tuna in logistic process(L1 and L2)is in sale after 48 h when it thawed from-55℃.Especially for L2 group,it was decreased significantly at 2℃.