食品级Tween 80微乳对红茶茶汤沉淀控制作用的研究

Study on deposition control of Red Tea Beverage with food-grade Tween-80 microemulsion

为研究食品级Tween80微乳对红茶茶汤沉淀的控制作用，采用加水滴定法制备了以Tween80为表面活性剂．柠檬烯为油相，1，2-丙二醇、聚乙二醇400、无水乙醇为助表面活性剂的微乳体系，根据拟三元相图微乳有效区域面积、微乳增溶水相能力和微乳温度稳定性等指标确定了空白微乳的处方，并研究了微乳对红茶茶汤特性以及茶汤内沉淀组分含量的影响。结果表明，空白微乳处方为：表面活性剂和助表面活性剂质量比Km值5：5，油相与表面活性剂质量比（简称油剂比）2：8和1：9；微乳液抑制红茶茶汤沉淀的最佳工艺为：油剂比1：9、含水量60％、添加量3—5mL；微乳液处理后的红茶茶汤澄清透明无沉淀，茶汤中可溶性蛋白质、茶多酚、咖啡碱和儿茶素的保留率分别为98．8％、98．9％、98．1％和97．4％。

In order to study the effect of Tween-80 microemulsion on deposition control of red tea beverage,food- grade microemulsions were prepared with tween-80 as surfactant（S）, limonene as the oil phase（ O）, propylene glycol, polyglycol 400 and ethanol as cosurfactant （CS） by using aqueous titration method.The area of microemulsion regions and water content of microemulsion were studied to determine the formula of microemulsion, and the thermal stability of microemulsion was also researched.The optimal technology was determined by studying the effect of microemulsion on the characteristics, transmittance and components in deposition of red tea beverage. The results indicated that the emulsion systems with ethanol as cosurfactant, Km 5：5 and oil-surfactant mass ratio 2：8 and 1：9 were used to control the deposition of red tea beverage.The optimal technology was：oil-surfactant mass ratio 1：9 ,water content 60% ,dose of microemulsion 3-5mL.Under this optimal technical condition,the retention rate of soluble protein,tea polyphenols,caffeine and catechin were 98.8% ,98.9%, 98.!% and 97.4% respectively.