ass日本风韵熟妇pics男人扒开女人屁屁桶到爽|扒开胸露出奶头亲吻视频|邻居少妇的诱惑|人人妻在线播放|日日摸夜夜摸狠狠摸婷婷|制服 丝袜 人妻|激情熟妇中文字幕|看黄色欧美特一级|日本av人妻系列|高潮对白av,丰满岳妇乱熟妇之荡,日本丰满熟妇乱又伦,日韩欧美一区二区三区在线

βCarotene is used as a precursor of vitamin A with potent antioxidant activity through singlet oxygen quenching and deactivation of free radicals. Nevertheless, the chemical instability of βcarotene limits its utilization as a nutraceutical ingredients in food industry. Tea polyphenols are often regarded as a highly effective antioxidant for some food applications. Antioxidants such as (-)epigallocatechin3gallate (EGCG) can play dual role in lipid oxidation in oilinwater emulsions in that it can scavenge free radicals but can also reduce transition metals to make them more prooxidative. Therefore, it is important to test the effect of EGCG on βcarotene degradation before it was used in foods. The chemical properties of βcarotene emulsions were characterized, which were stabilized by αlactalbumin (αLA) at different pH values with EGCG as antioxidant. βCarotene concentration and color during storage as well as interfacial EGCG concentration of the emulsions were measured. EGCG can inhibit βcarotene degradation in emulsions at both pH values. After 7 d storage, the percentage of βcarotene remained in the emulsions at pH value of 2.0 without EGCG and with 0.5000% EGCG was 50.45% and 89.37%, respectively. When the maximum concentration of EGCG (0.1000%) was added to the emulsion at pH value of 7.0, 93.48% of the total βcarotene remained after 7 d storage. The color was changed by EGCG addition in emulsions at pH value of 7.0, however, EGCG had no effect on the color of emulsions at pH value of 2.0. The concentration of interfacial EGCG was higher in the emulsions at pH value of 7.0 than that in the emulsions at pH value of 2.0 which can result in higher βcarotene remaining rate in the emulsions at pH value of 7.0.