甜菜粕碱溶性多糖的提取、结构及乳化特性分析  

Extraction, Structure and Emulsifying Property of Alkaline-extracted Polysaccharide from Sugar Beet Pulp

作　　者：于淑娟 林嘉伟 郭晓明 艾超[1] YU Shujuan;LIN Jiawei;GUO Xiaoming;AI Chao(School of Food Science and Engineering,South China University of Technology,Guangzhou 510640,Guangdong,China)

机构地区：[1]华南理工大学食品科学与工程学院

出　　处：《华南理工大学学报（自然科学版）》2019年第8期48-56,共9页Journal of South China University of Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(31601423,31771931);中国博士后科学基金资助项目(2018T110872);华南理工大学中央高校基本科研业务费专项资金资助项目(2017BQ099)~~

摘　　要：甜菜粕是甜菜糖产业的大宗副产物,合理利用甜菜粕及其二次废粕是提升我国甜菜制糖产业经济价值的重要途径.文中以甜菜果胶(SBP)加工剩余的废粕为原料,采用热碱法(碱用量1~4meq/g,温度90℃,提取时间1h)提取出5种碱溶性多糖(AEP),考察碱用量对AEP的产率、结构及乳化特性的影响.实验结果表明:随着碱用量的增大,AEP的半乳糖醛酸及阿魏酸含量逐渐下降,中性糖含量和重均分子量逐渐提高;碱用量为2.5meq/g提取所得的AEP2.5产率最高(为35.6%),其蛋白含量高达20.77%;碱用量对AEP乳化特性的影响显著;AEP1.0、AEP2.5的乳化活性较高,AEP2.0、AEP3.0和AEP4.0次之且与SBP相当;AEP新鲜乳液中小油滴(体积平均粒径d4,3<1μm)的比例高于SBP新鲜乳液(p<0.05);AEP2.5的乳化活性及稳定性均超过SBP,由两者制备得到的新鲜乳液的d4,3分别为0.847和0.958μm,在55℃下存放7d后,其d4,3分别增大至0.911和1.507μm;AEP2.5及SBP所制备的乳液达到最小粒径(分别为0.404和0.825μm)所需要的临界质量分数分别为2.50%、1.25%.Sugar beet pulp is a main by-product of beet sugar industry.The comprehensive utilization of sugar beet pulp and its secondary pulp is critical to add value to the beet sugar industry.Five alkaline-extracted polysaccharides(AEP)were extracted from the remaining pulp of sugar beet pectin(SBP)by using an alkaline extractant(alkali dosage 1~4 meq/g)at 90℃for extraction duration of 1 h.Effects of alkali dosage on the yield,structure and emulsify properties of AEP were investigated.The results show that,with the increase of alkali dosage,both the galacturonic acid and ferulic acid contents will decrease,whereas both the neutral sugar content and weight-average molar mass will increase.AEP2.5(extracted at alkali dosage 2.5 meq/g)has the highest yield(35.6%)and its protein content is 20.77%.Emulsifying performance of AEP is influenced by alkali dosage;AEP1.0 and AEP2.5 have superior emulsifying activities than the remainder,while AEP2.0,AEP3.0,AEP4.0 and sugar beet pectin have comparable emulsifying activities.AEP fresh emulsion contains higher proportions of small droplets(volume average particle size d4,3<1μm)than SBP fresh emulsion.AEP2.5 exhibited better emulsifying activity and stability than SBP as indicated by their different d4,3 values(0.847μm for AEP2.5 versus 0.958μm for SBP);d4,3 increase to 0.911μm and 1.507μm for AEP2.5 and SBP respectively after 7 days’storage at 55℃.At critical concentrations of 2.50%and 1.25%,AEP2.5 and SBP,respectively,gave their optimum emulsifying perfor-mances with d4,3 values of 0.404μm and 0.825μm.

关 键 词：碱溶性多糖 甜菜粕 乳化活性 乳化稳定性 结构分析 

分 类 号：TS201.7[轻工技术与工程—食品科学]