不同干燥方法对乳蛋白氧化及大鼠组织氧化还原状态的影响.docVIP

 不同干燥方法对乳蛋白氧化及大鼠组织氧 化还原状态的影响# 5 10 15 20 25 30 35 40  摘要：目的 研究鲜奶经过喷雾干燥和冷冻干燥后并添加高低剂量双酪氨酸，长期摄入对大 鼠机体氧化还原状态的影响。方法：通过对全脂乳及脱脂乳喷雾干燥处理及全脂乳冷冻干燥 处理，制备大鼠日粮并进行长期（5 周）饲喂，宰杀后测定肝脏、空肠、肾脏、等组织抗氧 化指标（丙二醛 MDA、总氧化能力 T-AOC、氧化酶类等）及蛋白质氧化指标（3-硝基酪氨 酸、双酪氨酸、晚期氧化蛋白等）。结果：组织抗氧化指标测定，脱脂组和冷冻组 GSH/GSSG、 总氧化能力、氧化酶类（SOD、CAT）显著高于添加高剂量双酪氨酸组，MDA 含量显著高 于添加高剂量双酪氨酸组，蛋白质氧化指标测定中，脱脂组和冷冻组 3-硝基酪氨酸、晚期 氧化蛋白、双酪氨酸、4-羟基壬烯酸显著高于添加高剂量双酪氨酸组，硫氧还蛋白显著高于 高剂量双酪氨酸组。结论：不同的干燥方法对奶粉造成的氧化程度不同，高剂量蛋白质氧化 产物双酪氨酸会显著影响机体氧化还原状态，导致机体失衡。 关键词：喷雾干燥；乳蛋白氧化；氧化还原状态 中图分类号：F407.82 Effects Of Drying Methods On Oxidation Of Dairy Protein And Redox State Mo Ling, Lei Guowei, Shi Yonghui (Insititute of food Nutrition and function factor,school of food science and technology,Jiangnan university, JiangSu WuXi 214122) Abstract: The oxidation of food proteins is currently one of the most innovative research topics within the food science filed. Objective: To investigate the redox state effects on rats which were treated with dairy protein modified by spray drying and freeze drying diet. Methods: Whole milk and skim milk was processed by spray drying (entering air temperature was 170℃, leaving air was 80℃),while the whole milk was processed by freeze drying. The rats were divided into 5 groups, consumed different diets for 5 weeks, Then detected the redox-related indicators(MDA、T-AOC、 SOD、CAT) and protein oxidation indicators(3-NT、Dtyr、AOPP). Results: Compared with the skim milk group and freeze drying group, the GSH/GSSG、T-AOC、SOD、CAT、Trx of the group which was added high doses dityrosine was significantly decreased, while the 3-NT、AOPP、Dtyr、 HNE was increased significantly. Conclusion: Different methods of drying and the fat content would cause different oxidation to milk powder, high doses dityrosine can cause a high oxidative stress in rats. Keywords: spray drying; oxidation of dairy protein; the redox state 0 引言 蛋白质是细胞内三大生命物质之一，机体需要摄入大量蛋白质以供生命活动所需，蛋白 质是食品的主要组成成分，但是在食品的加工和贮藏期间受到氧化损伤后会引起食品品质的 下降，而氧化修饰的蛋白质产物在机体中积累肯能导致机体产生病理变化[1-2]。很多相关体 内蛋白质氧化的研究都已证实