未漂洗鱼糜冻藏过程中晚期糖化终末产物形成及机制

The Formation of Advanced Glycation End-products of Unwashed Surimi during Frozen Storage and Its Underlying Mechanism

为探讨未漂洗鱼糜冻藏过程中晚期糖化终末产物(AGEs)的形成规律,将鱼糜样品在不同温度(-18℃和-60℃)下冻藏,于第0,15,30,45,60天测定其AGEs含量及脂肪氧化指标(TBA值)、蛋白质氧化指标(羰基含量、活性和总巯基含量、Ca2+-ATPase活性),分析其变化规律和相关性。结果表明:鱼糜样品在-18℃冻藏60 d,其Nε-羧甲基赖氨酸(CML)和Nε-羧乙基赖氨酸(CEL)含量分别较第0天增加了71.67%和88.24%,而在-60℃冻藏60 d仅增加了59.62%和62.11%,表明超低温(-60℃)冻藏有利于抑制AGEs形成;加热后,鱼糜样品AGEs(CML和CEL)含量增加了约1.05~1.23倍。冻藏过程中样品的TBA值呈先增后降趋势;蛋白质羰基和活性巯基含量逐渐上升,总巯基含量和Ca2+-ATPase活性逐渐降低,且与AGEs含量显著相关(P<0.05)。相对于-18℃冻藏组,-60℃冻藏抑制上述脂质和蛋白质氧化指标的变化,与抑制AGEs形成的趋势一致。说明冻藏温度和时间均对未漂洗鱼糜AGEs的形成有重要影响,而冻藏过程中脂肪和蛋白质氧化是AGEs形成的重要原因。

In order to explore the formation and underlying mechanism of advanced glycation end products(AGEs)of unwashed surimi during frozen storage,the contents of advanced glycation end-products(AGEs),lipid oxidation(TBA value)and protein oxidation(the content of protein carbonyl groups,reactive and total sulfhydryl groups)of unwashed silver carps were measured at 0,15,30,45 and 60 days of frozen storage at different temperatures(-18℃/-60℃),and their varying regularity and correlation were analyzed.The results showed thatthe levels of Nε-carboxymethylysine(CML)and Nε-carboxyethylysine(CEL)for samples stored at-18℃increased by 71.67%and 88.24%at the 60th day compared to those for fresh samples(0 day),while those for samples stored at-60℃increased by 59.62%and 62.11%,indicating ultra-low temperature(-60℃)was conducive to the inhibition of AGEs formation.Moreover,the levels of AGEs in surimi samples were increased by about 1.05-1.23 times after being heat-treated.During frozen storage,the TBA values of surimi increased firstly and then decreased,and the content of protein carbonyl and active sulfhydryl groups gradually increased,while the content of total sulfhydryl groups and Ca2+-ATPase activity gradually decreased,which was significantly correlated to the change in AGEs content(P<0.05).Compared with-18℃frozen storage group,frozen storage at-60℃inhibited the changes of above lipid and protein oxidation indexes,which was consistent with its inhibition on AGEs formation.These results revealed that AGEs formation in unwashed surimi samples was affected by frozen storage temperature and time,and lipid and protein oxidation during frozen storage was an important cause to their AGEs formation.