基于铝离子梯次浓度胁迫对羊尾脂氧化的响应

Response of Lipid Oxidation in Tail Fat of Sheep by Al3+Stress

通过设置不同浓度Al^(3+)处理阿勒泰羊尾脂,研究其4℃贮藏过程中氧化诱导期、氧化指标及其脂肪酸组成的变化。结果表明:羊脂氧化诱导期时间呈现前移,随着金属Al离子处理浓度的增加诱导期缩短,2 mol/L和5 mol/L Al^(3+)处理组氧化诱导期的时间较对照组提前最多,达到了15 d;pH值随着时间呈现波动下降趋势,较低浓度Al^(3+)处理的pH值在贮藏初期短暂地上升,之后迅速下降,较高浓度处理组pH值在整个贮藏实验过程中始终保持下降趋势,2 mol/L和5 mol/L Al^(3+)处理的pH值下降最多(P<0.05),贮藏27 d分别降至4.6和4.4;不同浓度梯度Al^(3+)处理组的TBARS值都显著高于对照组,随着Al浓度的增加,TBARS值增加速率也随之升高,Al^(3+)处理浓度与TBARS值呈现正相关;脂肪酸组成总体呈现饱和脂肪酸含量增加,不饱和脂肪酸含量减少,0.5 mol/L Al^(3+)处理后饱和脂肪酸含量增加了23.76%,0.1 mol/L Al^(3+)处理组不饱和脂肪酸含量下降了25.62%。

Experiments of Altay sheep tail fat were set up with different Al^(3+)stress gradients in this study,variation rules of initial autoxidation stage,oxidative indexes and fatty acid composition were investigated at 4℃during stage.The result showed that the initial autoxidation stage of lipid oxidation moved forward,initial autoxidation stage was shortened,the initial autoxidation stage of lipid oxidation was the shortest after 2 mol/L and 5 mol/L Al^(3+) treatment,it reached 15 days.pH fluctuated and decreased with the increase of storage time.At the initial storage,pH was brief increase with lower concentration,and then it went down really fast,pH kept decreasing with high concentration treatment during the whole storage time.The rate of descent is the fastest after 2 mol/L and 5 mol/L Al^(3+) treatment.It reached 4.6 and 4.4 after 27 days.The TBARS values of tail fat with different Al^(3+) stress gradients were significantly higher than control group,the increasing rate of TBARS increased as Al^(3+) concentration was increased.There was a positive correlation between Al^(3+) concentration and TBARS value.There was a marked change in the fatty acid composition,saturated fatty acid content was increased and the content of polyunsaturated fatty acid was decreased.After treatment 0.5 mol/L Al^(3+) group,saturated fatty acid content was increased by 23.76%;After treatment 0.1 mol/L Al^(3+) group,the content of unsaturated fatty acid was decreased by 25.62%.