【作者】 张凡； 吕欣； 王欣；

【Author】 Zhang Fan;Lü Xin;Wang Xin;College of Food Science and Engineering,Northwest A&F University;

【机构】 西北农林科技大学食品科学与工程学院；

【摘要】 在亚临界水提取制备植物多糖过程中,其微环境变化对多糖分子特性具有显著影响,为阐明亚临界水微环境制备过程对苹果渣果胶分子特性影响规律,本研究通过调控亚临界水提取温度(100-180℃)和提取时间(0-15min),制备系列苹果渣果胶多糖样品20种,并对其化学构成、理化特性、流变特性及抗氧化活性等进行分析对比。结果表明:亚临界水提取温度对果胶多糖提取得率及分子特性影响显著,可分为低温区(100-120℃),中温区(140℃),高温区(160-180℃);提取时间在高温区对果胶多糖分子特性影响显著强于低温及中温区;低温区果胶多糖分子质量、酯化度较高,样品色泽较浅,中温区提取得率较高,高温区果胶多糖分子质量较小,表现出了较强的体外抗氧化活性。研究证实亚临界水微环境能够显著影响果胶多糖及其它植物多糖选择性提取效率,以及多糖提取-降解之间的平衡关系。本研究结果对于调控亚临界水微环境定向制备果胶多糖提供了基础的数据资料,有助于促进亚临界水广泛应用于其它植物多糖的提取及定向制备。更多还原

【Abstract】 During the extraction process of plant polysaccharide by subcritical water,the variation of subcritical water microenvironment had significant influence on the molecular properties of polysaccharides.For the purpose to illuminate the influence of subcritical water microenvironment on the pectic polysaccharides from apple pomace,20 polysaccharide samples were prepared by the regulation of extraction temperature(100-180 ℃) and time(0-15 min) of subcritical water in the present study,as well as the investigation of the chemical composition,physiochemical properties,rheological properties and antioxidant activity of these samples.Results indicated that extraction temperature of subcritical water had a significant influence on the both yield and molecular properties of the pectic polysaccharide,which could be divided into low temperature zone(100-120 ℃),middle temperature zone(140 ℃) and high temperature zone(160-180 ℃).In addition,the extraction time showed more intensively influence at high extraction temperature zone that the low or middle temperature zone.Moreover,the molecular weight and esterification degree of pectic polysaccharide was higher at low temperature zone,as well as the more lightly color of the samples.It was also found that high yield of pectin was obtained at middle temperature zone,and the samples of lower molecular weight and greater antioxidant activity was extracted at high temperature zone.Therefore,based on the results,it was proved that the microenvironment of subcritical water significant influenced the selectivity and efficiency of pectic polysaccharide extraction,as well as the balance of the polysaccharide extraction-degradation during the preparation process.The present study provided basic information for the directional preparation of pectic polysaccharide by subcritical water,moreover,which also promotes the application of subcritical water to extraction or directional preparation of other plant polysaccharides.更多还原