Na^+和Ca^(2+)浓度对魔芋葡甘聚糖与黄原胶凝胶动态流变特性的影响  

Effects of content of Na^+ and Ca^(2+) on dynamic rheological properties of mixed gel system of konjac glucomannan and xanthan gum

作　　者：傅玉颖[1,2] 沈亚丽[1] 陈国文[1] 王美[1] 李肖蒙 张豪 倪俊杰 Fu Yuying;Shen Yali;Chen Guowen;Wang Mei;Li Xiaomeng;Zhang Hao;Ni Junjie(school of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, 310018;Hangzhou College of Commerse, Zhejiang Gongshang University, Hangzhou, 310018)

机构地区：[1]浙江工商大学食品与生物工程学院,杭州310018 [2]浙江工商大学杭州商学院,杭州310018

出　　处：《农业工程学报》2018年第1期301-307,共7页Transactions of the Chinese Society of Agricultural Engineering

基　　金：浙江省食品科学与工程重中之重一级学科开放基金(JYTsp20142111)

摘　　要：为了探讨盐离子对魔芋葡甘聚糖(konjac glucomannan,KGM)与黄原胶(xanthan gum,XG)复配凝胶体系动态流变学特性的调控机制,该文以KGM-XG(konjac glucomannan-xanthan gum,KGM-XG)复配凝胶为研究对象,选取了具有代表性的Na+与Ca2+,按照1~15 mmol/L的浓度分别加入到KGM-XG复配凝胶中,测定复配凝胶体系的动态流变学特性,即应变扫描、应力扫描、频率扫描、温度扫描、蠕变-恢复等。结果表明:盐离子的加入会破坏KGM与XG形成的空间网络状结构,造成复配凝胶体系弹性降低,同时盐离子的加入会使得复配凝胶体系的溶胶-凝胶转化温度降低,凝胶体系的损耗因子不断升高。Ca2+由于具有更高的价态,因此对KGM-XG复配凝胶体系的凝胶强度减弱作用更强,但高浓度的Ca2+能在一定程度上提升其黏弹性质。研究结果可为含有KGM-XG复配凝胶的体系提供从质构设计到工业生产等多方面的实践指导。KGM(konjac glucomannan)is a water-soluble and high-molecular-weight polysaccharide extracted from the roots of Amorphophallus Kojac plant.D-glucose and D-mannose are bonded byβ-1,4pyranoside bonding,and therefore,KGM is hard to be digested by the human.Due to the unique characteristic,KGM has been applied to a wide range of products as nutritional supplements for constipation,obesity,high cholesterol,acne vulgaris and type2diabetes.KGM often serves as emulsifier or thickener in food or pharmaceutical industries,however,thickening effect of KGM is not strong enough for products requires.The synergistic effect has been reported between the KGM and carrageenan or xanthan gum(XG),and thickening effect of KGM could be greatly enhanced once the XG or carrageenan has been added.XG is popularized for its outstanding thickening effect and synergistical effect with other polysaccharides.It is interesting to find that these2kinds of non-gelling or weak gelling polysaccharides could gel at low concentration once they were mixed.Several factors including pH value,temperature and salt concentration affect the properties of KGM-XG mixed gel.Investigation on the regulatory mechanism of salt on the dynamic rheology properties of KGM-XG mixed gel has been conducted in this paper.Different concentration of salt ranging from1to15mmol/L was added into the KGM-XG mixed gel respectively,and the dynamic rheological properties were measured through strain sweep,stress sweep,frequency sweep,temperature sweep,creep-recovery test.Results show that the addition of salt will compromise the steric net structure,and Na+will screen the electrostatic repulsion of XG and lead to the ordering of XG molecular conformation,thus weakening the crosslinking between XG and KGM.Actually,KGM combines XG through hydrogen bonds,since KGM is in disordered state,and synergistic effect between XG and KGM is on the basis of massive hydrogen bonds,some of the bonds are on the backbone of XG,while some of the bonds are on the side chain.The ordering of XG actuall

关 键 词：凝胶 流变 应变 魔芋葡甘聚糖 黄原胶 盐离子 

分 类 号：TS201.7[轻工技术与工程—食品科学]