回添法糙米粉制备及其糊化与储藏特性研究

Preparation, Pasting and Storage Properties of Brown Rice Flour with Refilling Method

通过气流膨化与挤压膨化分别处理米糠,并研究米糠处理前后基本成分及其吸水性指数与脂肪氧化酶酶活的变化。选择挤压膨化处理的米糠回添到湿磨法制备的白米粉中,制得回添法糙米粉,将其与湿磨法制得的全粉碎糙米粉和白米粉的糊化特性及储藏特性进行比较。结果表明,3种米粉的糊化特性有显著性差异(P<0.05),除糊化温度外,白米粉的峰值黏度、最低黏度、衰减值、最终黏度和回生值均最高,回添法糙米粉的峰值黏度、最低黏度、回生值和糊化温度均显著高于全粉碎糙米粉,更接近白米粉的糊化特性。在不同储藏温度期间,3种米粉的脂肪酸值均有明显的升高趋势,其中白米粉最低,全粉碎糙米粉最高,回添法糙米粉的脂肪酸值更接近于白米粉的脂肪酸值。因此用挤压膨化处理的米糠制得的回添法糙米粉的糊化特性及储藏特性优于全粉碎糙米粉,更接近于白米粉的糊化特性及储藏特性,用挤压膨化处理米糠并制备回添法糙米粉是一种糙米粉制备的较好方法。

The rice bran was processed by explosion-puffing and extrusion respectively,and the changes of the basic components and its water absorption index and lipoxygenase activity before and after the rice bran treatment were studied.The rice bran selected by extrusion was added back to the white rice flour prepared by the wet grinding method to prepare the refill brown rice flour,and then compare the pasting properties and storage properties of whole grinding brown rice flour and white rice flour with the refill brown rice flour.The results showed that there was a significant difference in the pasting properties of the three types of rice flour.In addition to the pasting temperature,the peak viscosity,trough viscosity,breakdown,final viscosity and setback of the white rice flour were the highest.The peak viscosity,trough viscosity,setback and pasting temperature of the refill brown rice flour were significantly higher than the whole grinding brown rice flour and closer to the pasting properties of white rice flour.During storage at different temperatures,the fatty acid values of the three types of rice flour have a clear upward trend,among which white rice flour is the lowest,and the whole grinding brown rice flour is the highest.The fatty acid value of refill brown rice flour is closer to that of white rice flour.Therefore,the pasting properties and storage properties of the refill brown rice flour prepared by extruded rice bran are better than that of the whole grinding brown rice flour,and are closer to the pasting properties and storage properties of white rice flour.Using rice bran treated by extruding and prepare the refill brown rice flour is a better method for preparing brown rice flour.