小麦中粗灰分的快速测定方法研究

Study on rapid determination method of crude ash content in wheat flour

以河南省种植的强筋、中筋、弱筋小麦为样品,将超声波辅助浸提小麦粉溶液的电导率值与国标法测定的灰分值对照,建立了快速测定小麦中粗灰分的数学模型。结果表明,强筋小麦灰分和电导率的拟合方程为κ=10-4×1 600x＋592.19,r为0.990 0,测定相对误差-4.9%~5.3%。中筋小麦的拟合方程为κ=-1411.5×0.18x＋700.02,r为0.877 6。弱筋小麦拟合方程为lglgκ=0.089lglgx＋0.505 3,r为0.969 1,测定相对误差为-1.5%~2.8%。强、中、弱筋全部小麦样品灰分含量和电导率的拟合方程为κ=502.920 463x0.400 236,r为0.875 2。将测定样品的电导率值代入拟合方程,可以快速计算出小麦灰分的相对含量,经F检验和t检验,该法和国标法相比无显著性差异,具有快速准确、操作简单,利于普及推广的显著优点,为现场快速测定小麦灰分提供了理论依据和技术支撑。

A new method of rapidly determining wheat ash was set up using strong,middle and weak gluten as sample. Mathematical models were set up by measuing the ash content using ultrasonic extraction. The results showed that the fitting equation between ash and conductivity of strong gluten wheat was r=10-4 ×1 600x ＋592.19 （r=0.9900）. The relative error was from -4.9% to 5.3%. The fitting equation between ash and conductivity of middle gluten wheat was K = - 1 411. 5 × 0. 18x ＋ 700. 02 （r = 0. 877 6）. The fitting equation between ash and conductivity of weak gluten wheat was lglgK=0.0891glgx＋0.505 3 （r=0.969 1）. The relative error was from -1.5% to 2.8%. The fit- ting equation between ash and conductivity of all gluten wheat was K = 502. 920 463x^0.400236 and r was 0. 875 2. We can get ash napidly from model with conductivity. There is significant no difference between this method and the intenational method. The advantages of this method are rapid measurment,less labor and time, and energy source saving. The apparatuses are simple, cheap and easy to carry out. The purpose of this paper is to provide theoretical basis and reference for rapid prediction ash in wheat.