乙醇沉淀时间对苹果果胶性质的影响  

Effect of Ethanol Precipitation Time on Physicochemical Properties of Apple Pectin

作　　者：范会平[1] 彭凯[1] 胡小松[1] 吴继红[1] 廖小军[1] 

机构地区：[1]中国农业大学食品科学与营养工程学院果蔬加工教育部工程研究中心农业部果蔬加工重点开放实验室,北京100083

出　　处：《食品与发酵工业》2009年第10期49-54,共6页Food and Fermentation Industries

基　　金：农业部"948"项目--果胶产业化关键技术(No.2005-Z33);国家"十一五"支撑计划课题--苹果果胶系列产品与优质苹果汁开发及产业化示范(2006BAD05A13)

摘　　要：研究了乙醇沉淀时间对苹果果胶性质影响,乙醇沉淀5min所得果胶为组分1,沉淀5-90min所得果胶为组分2。组分1的得率、半乳糖醛酸和酯化度分别为7.72%、70.5%和80.2%,组分2相应的为1.62%、65.4%和86.5%,组分1的黏均分子质量高于组分2;组分1的总离子含量显著低于组分2,但两者的褐变指数和总多酚含量差异不显著;组分1和组分2的凝胶温度分别为90℃和86℃;组分1比组分2有更加稳定的三维网络结构。通过对2种组分0.01和0.02g/mL浓度溶液流变性质分析后发现,组分1的表观黏度、屈服应力及活化能要大于组分2。结果表明,组分1的得率、纯度、稳定性和流变学特性优于组分2。The effect of ethanol precipitation time on the physical-chemical properties of apple pectin was studied. Two fractions of pectin obtained by ethanol precipitation were F1 for the initial 5 min and F2 for the remaining 85 min. The solid yield, galacturonic acid and degree of esterification （DE） were 7.72% , 70.5 and 80.2% in F1, and 1.62% , 65.4 and 86.5% in F2, respectively. The average viscosity molecular weight （Mw ） of F1 estimated by Mark Houwink-Sakurada equation was higher than that of F2. However, the brown index and total phenolic content had not much difference for the two fractions. The gelling temperature （ Ts） of F1 and F2 were 90 ℃ and 86 ℃ , respectively. F1 showed stronger gelling ability than F2. The apparent viscosity, yield stress and activation energy value of F1 was significantly greater than that of F2.

关 键 词：苹果果胶 乙醇沉淀时间 半乳糖醛酸 酯化度 流变特性 

分 类 号：TS255[轻工技术与工程—农产品加工及贮藏工程]