The flow and viscoelastic behavior were measured by steady-shear and small-amplitude oscillatory experiments at 25℃,respectively.The aim of this paper was to provide meaningful guidance for Fenugreek Gum's application in various areas by the rheology analysis.The results showed that FG aqueous solutions exhibited an initial shear-thicking behavior,followed by a shear-thinning behavior above a critical value of shear rate,suggesting a non-Newtonian fluid characteristic.The experimental data were evaluated by the Herschel-Bulkey and Carreau models,results were founded to be well correlated to the Carreau model with a high R2.The hysteresis loop represented a certain thixotropic property of FG solutions,and showed concentration dependence.However,FG solutions at a concentration less than 0.35％ showed a negative value of thixotropic loop area,suggesting the structural breakdown and no recovery was measured in the corresponding experiment.The dynamical viscoelastic properties of FG aqueous solutions showed the storage and loss modulus increased with the increase of angular frequency and FG concentrations,and decreased with the increase of temperatures.In addition,the FG solutions exhibited a solid,elastic-like behaviour,while FG at a concentration of 0.1％ w/w exhibited a transition from a fluid-like to gel-like structure.%在特定温度(25℃)下,通过对葫芦巴胶(FG)溶液进行稳定剪切和小振幅振荡处理后,测定其触变性及粘弹性,以及通过Carreau和Herschel-Bulkey模型对FG溶液流动性进行评估.结果表明:FG溶液刚开始表现出剪切增稠特性,当超过临界剪切速率时表现为剪切变稀行为,表现出非牛顿流体特性.Herschel-Bulkey和Carreau模型对流动曲线的拟合表明实验结果更符合流变学的Carreau模型.触变测试表明FG溶液具有一定的触变性,FG溶液质量浓度越高,触变性越强,当FG溶液质量浓度小于0.35 g/dL时,触变环面积为负值,表明样品结构破坏且不能恢复.动态粘弹性测试表明FG溶液的储能模量和损耗模量随角频率和FG质量浓度的增大而增大,随着温度的升高而降低,并表现出类似于固体的弹性行为.
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