魔芋葡甘聚糖的流变特性研究

Rheological properties of konjac glucomannan

通过研究魔芋葡甘聚糖(KGM)溶胶粘度(η)分别与浓度、温度、溶胀时间及剪切速率的相关性,结果表明KGM的流变特性呈明显的非线性变化规律。KGM的η随浓度(C)增加呈指数关系递增;用三次多项式能良好拟合温度效应曲线和溶胀速率曲线;KGM溶胶属典型的假塑性流体,其流变曲线符合幂定律,进一步得出了粘性系数K和流动指数n随浓度和温度的变化趋势,其关系曲线可分别用幂函数和二次多项式拟合。实验得到效应的非线性曲线拐点,即浓度(0.70%)、温度(50℃)、时间(40min),以及K和n的非线性变化曲线,为KGM在食品工业中的合理应用和其质量评价提供可靠依据。

Remarkable non-linear change tendencies of theological properties of konjac glucomannan （KGM） were detected through analysis of the correlation between the viscosity （η） of KGM gum and KGM concentrations, temperatures, hydrated time and shear rates. The η increased exponentially with the increase of concentration （η = . 0005e^8.7994C）. Cubic polynomial regression equation could fit to temperature effect and hydrated rate data well. KGM gum belongs to pseudoplastic fluid, and its shear rheological curves conformed to the Power Law, and the change tendencies of viscosity factor （K） and flow index （n） correlated with concentration and temperature were also obtained, the curves can be fitted by power and quadratic polynomial equation, respectively. The effect inflection point of non-linear correlations, namely concentration （0.70%）, temperature （50℃） and hydrated time （40 min）, and non-linear correlation curves of K and n were acquired, which can provide reliable foundation for rational applications of KGM in food industry and its grade estimation.