To study the effects of non-starch polysaccharide on the rheological properties of starch, we deter-mined the viscoelastic properties of the mixtures of corn starch/locust bean gum 1.2:0, 1.1:0.1, 1.0:0.2, 0.9:0.3, 0.8:0.4(mass ratio). The Power-Law model fitted the data of the static rheology with the correlation coeffi-cient of more than 0.99. The fluid index was less than 1, indicating that the mixture was pseudoplastic fluid. With the increase in the proportion of locust bean gum, the consistency coefficient of mixture increased signifi-cantly, fluid index decreased, pseudoplasticity enhanced. When the ratio of corn starch and locust bean gum was less than 0.9:0.3 (mass ratio), the increase was no longer significant. Dynamic rheological tests showed that the elasticity was large and the viscosity was moderate if the ratio of corn starch to locust bean gum mass ra-tio was less than 0.9:0.3(mass ratio). The elasticity was the smallest and the viscosity was the biggest when the ratio of corn starch to locust bean gum was 0.8:0.4 (mass ratio). The mixtures of corn starch/locust bean gum showed better synergistic thickening effects.%为研究非淀粉多糖类胶体对淀粉流变特性的影响,测定5组不同配比刺槐豆胶/玉米淀粉混合物0:1.2、0.1:1.1、0.2:1.0、0.9:0.3、0.4:0.8(质量比)的黏弹性.采用Power-Law模型对静态流变学试验数据进行回归拟和,决定系数R2均在0.99以上,流体指数n<1,表明玉米淀粉及两者混合体系属于假塑性流体;随着刺槐豆胶/玉米淀粉混合物质量比的提高,混合体系的稠度系数显著增加,流体指数降低,假塑性增强.当刺槐豆胶/玉米淀粉质量比小于0.3:0.9(质量比)时,稠度系数增加不再显著.动态流变学试验显示,刺槐豆胶/玉米淀粉质量比大于0.3:0.9(质量比)时,弹性较大,黏度适中.刺槐豆胶/玉米淀粉质量比为0.4:0.8(质量比)时,黏度最大,弹性最小,混合体系具有更好的协同增稠效果.
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