橡子全粉与淀粉糊化性质和消化性的研究

The pasting properties and digestibility of the acorn powder and starch

以橡子全粉、脱单宁后的橡子全粉(橡子全粉DT)和从橡子粉中提取的淀粉为研究对象,利用RVA黏度仪分析了橡子全粉和橡子淀粉的糊化性质。RVA图谱表明,3种物料的糊化温度大小关系为橡子全粉DT>橡子全粉>橡子淀粉,而它们的峰值黏度、谷值黏度、破损值、最终黏度及回生值大小关系却均为橡子淀粉>橡子全粉DT>橡子全粉。利用体外消化模型对橡子淀粉进行消化实验结果显示,随着橡子全粉中单宁的脱除,淀粉的可消化率随之增加,表现出快速消化淀粉(RDS)含量在增加。

A new kind of low loss ZrTi2O6 filled polytetrafluoroethylene （PTFE） microwave composite substrates were fabricated through the hot-pressing process. The microwave dielectric properties of the composites were measured using dielectric resonator method （18-12 GHz）. The relative permittivity （εr） and loss tangent （tanδ） of the composites increase with an increase of the volume fraction of ZrTi2O6 ceramic （0-46%）. The experimental dielectric constants of the composites match well with the theoretically predicted values using Lichtenecker model. As the volume fraction of ZrTi2O6 ceramic increases, the thermal expansion coefficient and the temperature coefficient of dielectric constant decrease. The ZrTi2O6/PTFE composites exhibit a dielectric constant of 7.42 with a loss tangent of 0.0022 （10 GHz） at an optimum filler volume fraction of 46% ZrTi2O6.