亚麻籽胶-乳清蛋白改性物的制备及抗氧化性

Preparation and antioxidant activity of flaxseed gum-whey protein

利用亚麻籽胶对乳清蛋白进行糖基化改性,以接枝度为指标进行单因素及正交试验得到最佳反应pH,温度和时间,并对所得亚麻籽胶-乳清蛋白复合物进行扫描电镜、红外光谱、抗氧化性等测定。得到最佳制备条件为:pH 11、110℃、60 min。产物表面结构的变化、傅立叶变换红外光谱以及荧光分析证实了结合物的产生。抗氧化性测定结果显示,无论亚麻籽胶是否脱蛋白,其与乳清蛋白复合物的抗氧化能力均高于同等浓度下单一的亚麻籽胶和乳清蛋白,未脱蛋白亚麻籽胶所得复合物的抗氧化能力优于脱蛋白亚麻籽胶复合物。相关性分析表明,亚麻籽胶添加量与其所得复合物的接枝度、抗氧化能力均呈正相关。研究表明亚麻籽胶与乳清蛋白结合增强了两者的功能性质。

The glycosylation of whey protein(WP)was modified by flaxseed gum(FSG).The optimal reaction conditions were obtained by single factor and orthogonal experiments with grafting degree as the index.The obtained complex(FSG-WP)was determined by scanning electron microscopy,infrared spectroscopy,and antioxidant activity.The optimum reaction conditions were as follows:pH 11,110°C and 60 min.The occurrence of glycosylation reaction was confirmed by the changes in the FSG-WP microstructure,the newly formed C—N bonds in FT-IR of conjugates compared with WP and the fluorescence analysis.The results of the antioxidant test showed that the antioxidant capacity of FSG-WP was higher than that of FSG and WP at the same concentration,regardless of whether FSG was deproteinized or not.Furthermore,the complexes made from non-deproteinized FSG showed higher antioxidant activity than that of the deproteinized FSG.Correlation analysis showed that the amount of FSG was positively correlated with the grafting degree and antioxidant capacity of FSG-WP.This study showed that the conjugation of FSG and WP enhanced the functional properties of both.