Functional properties of various molecular weights and functional groups on pectin

1992财政年度的结果如下：制备了不同分子量和官能团的果胶。每种果胶都是由市售的高甲氧基果胶和新鲜水果通过酸去甲基化方法制备的。我们分析了化学成分，并测量了分子分布（取决于科研预算）。然后我们澄清了甲氧基随着去甲基化时间的增加而减少，并且分子量分布向低分子量一侧移动。考察了阳离子对溶胶-凝胶过渡过程流变性能和黏性的影响。当微量Ca^<2+,>加入时，去甲基果胶的凝胶形成均匀，而当Mg^<2+>加入时，由于分子的捕获迅速结合，凝胶形成不均匀。用DSC法测定了阳离子对各种低甲氧基果胶溶液热性能的影响。测定了甲氧基含量的不同对凝胶的冻结峰温度、熔化峰温度和凝胶的焓有影响。阐明了不同分子量的果胶及其官能团在果胶溶胶-凝胶转变过程中的重要作用。(1)无花果果浆多糖的功能特性。(2)无花果果浆多糖水溶性溶胶和凝胶的流变特性。(3)考察了无花果果浆的结构。我们希望在未来研究水在溶胶-凝胶中的行为，以及各种添加物对阳离子的影响，并澄清不同分子量的果胶和官能团的功能特性。

The following results were obtained in the fiscal year1992.1. Prepared various molecular weights and functional groups of pectin. Each pectin was prepared from commercially high methoxyl pectin and fresh fruits by the acid-demethylating method. We analyzed the chemical composition, and measured the molecular distribution (dependent on the science research budget) by GPC. Then we clarified that the methoxyl groups decreased with an increase in demethylating time, and the molecular weight distribution shifted to the lower molecular weight side.2. The effect of cations on the rheological properties of the sol-gel transition process and the viscosity behavior were examined. A gel formation with demethylated pectin was appeared uniform with a slight addition of Ca^<2+,> but the behavior was not uniform when making gel with Mg^<2+> because catch of the molecules rapidly combined.3. The effect of cations on the thermal properties of various low methoxyl pectin solutions were measured by DSC. It was determined that the difference in the content of the methoxyl groups has an effect on the freezing peak temperature, the melting peak temperature and the enthalpy of gels. It was clarified that the pectins of different molecular weights and the functional groups were important in the sol-gel transition of the pectins.4. Functional propertics of polysaccharide of jelly fig. (1) Factors affecting the gelation behavior of aqueous components extracted from jelly fig. (2) Rheological properties of aqueous polysaccharide sols and gels prepared from jelly fig. (3) The texture profiles of jelly fig were examined. We want to examine the behavior of water in the sol-gel and the influence of various additions on the cations as well as clarify the functional properties of the pectins of different molecular weights and the functional groups in the future.