微量黏度仪区分糯性与非糯性大米粉的研究

Distinguishing Waxy and Non-waxy Rice Flour by Micro Visco-Amylo-Graph

首先通过单因素及正交试验,得到微量黏度仪的最优测试参数为:样品浓度7%、转速200 r/min、温度升降速率7℃/min。然后采用微量黏度仪测定米粉样品的糊化和黏度特性,结果表明:糯米粉与大米粉的开始糊化温度之间及最终黏度之间均没有显著性差异(p>0.05);糯米粉的峰值时间以及回生值显著低于大米粉样品,而峰值黏度和衰减值显著高于大米粉样品(p<0.05)。由此可知,采用微量黏度仪快速区分糯米粉与大米粉样品是可行的,其测定的峰值黏度、峰值时间、回生值以及衰减值是区分糯米粉与大米粉样品的较好指标。

The optimum parameters for running Micro Visco-Amylo-Graph were obtained with sample concentration of 7%, rotaing speed of 200 r/min and heating and cooling rate of 7 ℃/min through series of single factor experiments and an orthogonal experiment. The pasting properties of waxy and non-waxy rice flour samples were compared by Micro Visco- Amylo-Graph under the optimum parameters, and the results showed that there was no significant difference between waxy and non-waxy rice flour for both gelatinization temperature and final viscosity （P〉0.05）; Peak time of waxy rice flour was shorter, and setback was smaller than its counterpart; And both peak viscosity and breakdown of waxy rice flour were significantly larger than their counterparts of non-waxy rice flour. It was feasible to quick distinguish waxy and non-waxy rice by using Micro Visco-Amylo-Graph, and among several suitable criterion for distinguishing waxy and non-waxy rice were peak viscosity, peak time, setback and breakdown.