低浓度乙醇对魔芋葡甘聚糖理化特性及其结构影响的研究  

Effects of low-concentration ethanol on physicochemical properties and structure of konjac glucomannan

作　　者：胡艳 李悦[1,2] 吴玉萍 吴春华[3] 张甫生 HU Yan;LI Yue;WU Yuping;WU Chunhua;ZHANG Fusheng(College of Food Science,Southwest University,Chongqing 400715,China;National Demonstration Center for Experimental Food Science and Technology Education(Southwest University),Chongqing 400715,China;College of Food Science,Fujian Agriculture and Forestry University,Fuzhou 350002,China)

机构地区：[1]西南大学食品科学学院,重庆400715 [2]食品科学与工程国家级实验教学示范中心(西南大学),重庆400715 [3]福建农林大学食品科学学院,福建福州350002

出　　处：《食品与发酵工业》2024年第14期233-239,共7页Food and Fermentation Industries

基　　金：西南大学大学生创新创业训练计划项目(S202310635297);重庆市自然科学基金(cstc2018jcyjAX0002)。

摘　　要：为探究在低浓度乙醇下魔芋葡甘聚糖(konjac glucomannan,KGM)的性能和结构变化,拓宽其在食品领域的应用,以粗制魔芋葡甘聚糖为对象,研究其在低浓度乙醇纯化下的凝胶强度、黏度和结构的变化。结果表明,随着乙醇浓度增加和洗脱时间的延长,凝胶强度和黏度都呈现先上升后降低的趋势;随着洗脱次数的增加,凝胶强度和黏度呈现上升趋势。乙醇浓度33%(体积分数)纯化粗制魔芋葡甘聚糖30 min,洗脱2次后,与未经纯化处理KGM相比,凝胶强度和黏度分别显著提升了28.6%和34.7%。根据结构表征可知,粗制魔芋葡甘聚糖经过低浓度乙醇处理后,分子间氢键作用力增强,相对结晶度增高,局部形成有序的短程结构;同时平均粒径变化幅度不大,大小约为270.4μm;且KGM表面所含杂质减少,呈现规则的层状和褶皱分布。因此,通过调控低浓度乙醇纯化条件,可制得适应不同加工需求的KGM。To expand the application of konjac glucomannan(KGM)in the food industry,this study investigated the properties and structural changes of KGM under low-concentration ethanol.The changes in gel strength,viscosity,and structure of crude konjac glucomannan purified using low-concentration ethanol were investigated.The findings indicated that the gel strength and viscosity exhibited an initial increase followed by a subsequent decrease in response to the increase in ethanol concentration and elution time.Moreover,the gel strength and viscosity exhibited an upward trend as the elution times increased.The gel strength and viscosity of crude konjac glucomannan were significantly enhanced by 28.6%and 34.7%,respectively,after being purified using 33%(volume fraction)ethanol concentration for 30 min and elution twice.The structural characterization indicated that the intermolecular hydrogen bond force was enhanced after the crude konjac glucomannan was treated with low-concentration ethanol.With the increase of relative crystallinity,ordered short-range structures could be induced locally.The mean particle size bravely changed,and the size was about 270.4μm.Additionally,the impurities on the surface of KGM were reduced,appearing regular layered and fold distribution.As a result,KGM that is suitable for various processing requirements can be prepared by regulating purification conditions of low-concentration ethanol.

关 键 词：魔芋葡甘聚糖 纯化 凝胶强度 黏度 结构 

分 类 号：TS201.2[轻工技术与工程—食品科学]