挤压膨化对杂粮代餐粉营养品质及理化性质的影响

Effects of Extrusion on Nutritional Quality and Physicochemical Properties of Multigrain Meal Replacement Powder

以青稞、绿豆、黑豆、苦荞多种杂粮为原料,采用双螺杆挤压膨化技术制备杂粮代餐粉,分析其挤压前后营养成分、挥发性风味物质、晶体结构等理化性质的变化。结果表明:经挤压处理后杂粮代餐粉蛋白质、脂肪、水分、淀粉、总酚、总黄酮含量分别下降了2.83%、0.47%、4.45%、2.62%、17.89 mg/100 g、9.02 mg/100 g;膳食纤维和灰分变化不显著。风味贡献较大的醛类、醇类、杂环类物质有所增加,大大改善其风味。结晶结构由A型转变为V型,结晶度下降了24.97%。RVA、DSC结果显示,峰值黏度、最低黏度、崩解值、最终黏度、回生值和峰值时间分别下降了156、46、110、111、177 cP、2.2 min,焓变值下降为0.15 J·g^(-1)表明大部分的淀粉已糊化。凝胶质构结果显示,硬度及胶粘性分别下降了35.72 g、4.08 g,粘附力、内聚性、弹性、咀嚼性分别增加了5.11 g、0.19 Ratio、5.08 mm、1.98 mJ,赋予其良好的口感。粉体品质特性研究显示可溶性固形物含量、持水力增加,持油力减少;粉体特性明显改善,色泽变化明显。

Using highland barley,mung bean,black bean and Tartary buckwheat as raw materials,the multigrain meal replacement powder was set by twin-screw extrudation technology.The changes of nutrient composition,volatile flavor,crystal structure and other physicochemical properties were tested before and after extrudation.The results showed that the contents of protein,fat,moisture,starch,total phenol and total flavone of multigrain meal replacement powder were reduced by 2.83%,0.47%,4.45%,2.62%,17.89 mg/100 g and 9.02 mg/100 g,respectively.The changes of dietary fiber and ash were not significant.The aldehydes,alcohol and heterocyclic substances that contribute more to the flavor were increased,which greatly improved the flavor.The crystal structure changed from A-type to V-type,and the crystallinity reduced by 24.97%.RVA and DSC results showed that the peak viscosity,minimum viscosity,disintegration value,final viscosity,recovery value and peak time decreased by 156,46,110,111,177 cP and 2.2 min,respectively.The enthalpy change decreased to 0.15 J·g^(-1),indicating that most of the starch had been gelatinized.The results of gel texture showed that the hardness and adhesion decreased by 35.72 g and 4.08 g respectively,while the adhesion,cohesiveness,elasticity and capability increased by 5.11 g,0.19 Ratio,5.08 mm and 1.98 mJ respectively,giving it a good taste.The study of the quality characteristics of the powder showed that the content of soluble solid and the water holding capacity increased while the oil holding capacity decreased.The characteristics of power were obviously improved.The color changed obviously.