香豆胶与玉米淀粉混合物流变特性的研究

Study on rheological properties of fenugreek gum and corn starch mixtures

中文关键词:  香豆胶  玉米淀粉  糊化  流变性

英文关键词:fenugreek gum  corn starch  gelatinization  rheological property

中文摘要:

      目的 研究不同质量分数的香豆胶对玉米淀粉糊化混合物剪切流变特性与动态黏弹性的影响。方法 使用旋转流变仪测定玉米淀粉糊化的混合物剪切流变特性与动态黏弹性, 采用Herschel-Bulkley模型对剪切流变数据进行分析。结果 香豆胶与玉米淀粉糊化混合物是假塑性流体。随着香豆胶质量分数的增加, 混合物稠度系数K显著增加, 下行线流体指数n显著降低, 假塑性增强。动态黏弹性测定结果为: 混合物贮能模量(G')和损耗模量(G')都随香豆胶质量分数增大而增大, 损耗角正切tanδ＜1, 说明香豆胶的添加增大了混合物的黏弹性。结论 当香豆胶质量分数为8%时, 混合物黏性最大, 弹性最小, 混合物具有更好的黏弹性。

英文摘要:

      Objective To investigate the effects of fenugreek gum with different mass fractions on the shear rheological and dynamic viscoelastic properties of corn starch paste mixtures by rotational rheometer. Methods Shear rheological properties and dynamic viscoelasticity of corn starch gelatinized mixtures were measured by rotary rheometer. Herschel-bulkley model was used to analyze the shear rheological data. Results The pasting mixture of coumarin and corn starch was a pseudoplastic fluid. As the mass fraction of coumarin gum increased, the consistency coefficient K significantly was increased, the downline fluid index n was decreased significantly, and the pseudoplasticity was enhanced. The dynamic viscoelasticity measurement results showed that the energy storage modulus (G') and loss modulus (G') of the mixture were increased and the tangent value of loss tanδ was less than 1 with the increase of fenugreek gum mass fractions, indicating that the addition of coumarin gum increased the viscoelasticity of the mixture. Conclusion When the mass fraction of coumarin was 8%, the mixture had the highest viscosity and the lowest elasticity, and the mixture had better viscoelasticity.