苦荞淀粉制备工艺及其性质研究

Preparation Technology and Properties Study of Tartary Buckwheat Starch

以苦荞粉为原料,用0.3%碱液和石油醚处理样品中的蛋白质和脂肪。在单因素试验基础上,采用Box-Behnken中心组合试验响应面分析法,优化苦荞粉超声波辅助清除黄酮工艺,研究苦荞淀粉的实验室制备方法。通过DSC、SEM、XRD和RVA-3等仪器分析淀粉性质。分析结果表明:苦荞淀粉最佳黄酮清除工艺是:超声波提取温度59.7℃、提取功率648W、料液比1∶23.5。此时黄酮物质清除率率为90.02%。用此工艺制备的苦荞淀粉表面结构光滑、完整、无裂痕。其晶体结构是典型的A晶型,结晶度为29.89%,与谷物淀粉晶体结构特征吻合。糊化峰值黏度的RVU值为258.25,最终黏度的RVU值为389.58,样品糊化吸收热焓(ΔH)为10.2J/g。

The lab preparation method of tartary buckwheat starch was studied. Alkali solution（0.3%） and petroleum ether were used to clear the protein and fat of tartary buckwheat flour in this study. Making the use of Box-Behneken designs for response surface methodology on the basis of single factor experiment, the optimum technology was researched to remove flavonoids from tartary buckwheat flour with the auxiliary of ultrasonic. The instruments, such as DSC, SEM, XRD and RVA-3 were used to analyze the nature of the tartary buckwheat starch. The results shows that the best con- ditions for flavonoids to be extracted were a temperature of 59.7 ℃ and power of 628 W for ultrasonic extraction, a ma- terial-liquid ratio of 1：23.5, which the clearance of flavonoids was 90.02%. The tartary buckwheat starch made by this technique had a smooth and complete surface structure without any cracks on it. The crystal texture was typical Type A with crystallinity of 29.89%, and it was in accordance with the crystal texture of cereal starches. RVU value of 258.25 for gelatinization peak viscosity, 389.58 for final viscosity and heat content （Sd/） of 10.2 J/g for the sample to absorb in the process of gelatinization.