Li Qian, Shi Jinglan, Du Xiaolin, McClements David Julian, Chen Xiaoqiang, Duan Mengran, Liu Lu, Li Jing, Shao Yundong, Cheng Yong
National "111" Center for Cellular Regulation and Molecular Pharmaceutics, Key Laboratory of Fermentation Engineering (Ministry of Education), Hubei Key Laboratory of Industrial Microbiology, College of Bioengineering and Food, Hubei University of Technology, Wuhan, Hubei 430068, China.
National "111" Center for Cellular Regulation and Molecular Pharmaceutics, Key Laboratory of Fermentation Engineering (Ministry of Education), Hubei Key Laboratory of Industrial Microbiology, College of Bioengineering and Food, Hubei University of Technology, Wuhan, Hubei 430068, China.
Food Chem. 2021 Sep 30;357:129714. doi: 10.1016/j.foodchem.2021.129714. Epub 2021 Apr 1.
A natural antioxidant emulsifier, tea polysaccharide conjugate (TPC), was isolated from Chin brick tea. The impact of TPC on β-carotene stability and bioaccessibility in oil-in-water nanoemulsions was assessed. TPC exhibited strong antioxidant activity and could be used to fabricate stable nanoemulsions (d < 140 nm). The extent of lipid digestion was considerably lower for lipid droplets coated by TPC (68%) than Tween 80 (94%) or whey protein isolate (WPI) (89%), probably because TPC formed interfacial layers that hindered the access of lipases to lipids. The chemical stability of β-carotene in TPC-nanoemulsions was markedly higher than in those formulated with Tween 80 or WPI due to the high antioxidant activity of TPC. The bioaccessibility of β-carotene (20-30%) was independent of emulsifier type. TPC from Chin brick tea can therefore be used as a dual-purpose functional ingredient in emulsified foods.
从青砖茶中分离出一种天然抗氧化剂乳化剂——茶多糖共轭物（TPC）。评估了TPC对水包油纳米乳液中β-胡萝卜素稳定性和生物可及性的影响。TPC表现出较强的抗氧化活性，可用于制备稳定的纳米乳液（直径<140nm）。TPC包被的脂质小滴的脂质消化程度（68%）明显低于吐温80（94%）或乳清蛋白分离物（WPI）（89%），这可能是因为TPC形成了界面层，阻碍了脂肪酶与脂质的接触。由于TPC具有较高的抗氧化活性，β-胡萝卜素在TPC纳米乳液中的化学稳定性明显高于用吐温80或WPI配制的纳米乳液。β-胡萝卜素的生物可及性（20-30%）与乳化剂类型无关。因此，青砖茶中的TPC可作为乳化食品中的一种两用功能成分。
