挤压膨化与重组造粒茯苓复配谷物产品功能成分分析及淀粉体外消化特性评价

Analysis of Functional Components and Evaluation of in Vitro Starch Digestion Properties in Poria Cocos Compound Grain Products by Extrusion and Recombinant Granulation

以茯苓与谷物复配制得的营养粉及重组米为研究对象,探究挤压膨化及重组造粒对产品营养功能成分和碳水化合物体外消化特性(预期血糖反应)的影响。结果表明,挤压膨化比重组造粒更易导致红米多酚和苦荞黄酮损失,两种加工方式对薏苡仁酯及茯苓三萜酸含量的影响均不显著(P<0.05),但可改善茯苓多糖水溶性,产品中茯苓水溶性多糖含量增加率达52.57%~61.08%;与谷物原料相比,产品的快消化淀粉和抗性淀粉含量分别增加6.79%~24.12%和14.97%~43.30%,而慢消化淀粉含量减少21.73%~41.44%;添加20%的茯苓对产品快消化、慢消化、抗性淀粉含量均无显著影响(P<0.05),但对淀粉水解指数(Hydrolytic index,HI)和血糖负荷评估值(Evaluate glycemic load,EGL)影响显著(P<0.05),分别降低16.81%~18.40%和32.42%~36.63%,食用后可维持餐后血糖稳态化,血糖负荷较小。

In this paper, the effect of extrusion and recombinant granulation on functional components and in vitro digestion properties (expected glycemic response) in Poria Cocosproducts.compound grain products was investigated. The results showed that the loss of polyphenols in red rice and flavonoids in tartary buckwheat by extrusion were more than that by recombinant granulation. The content of coixenolide in adlay and terterpenes in Poria cocos by two processing methods were not significant (P<0.05). The water solubility of polysaccharides was improved by two processing methods, andthe content of water-soluble polysaccharide in processing products increased by 52.57%~61.08%. Compared with raw grains, the rapid digestible starch (RDS) and resistant starch (RS) in products increased by 6.79%~24.12% and 14.97%~43.30% respectively, however the slowly digestible starch (SDS) decreased by 21.73%~41.44%. The addition of 20% Poria cocos had no significant effects on the contents of RDS, SDS and RS(P<0.05), whereas it had significant effects on starch hydrolytic index (HI) and evaluate glycemic load (EGL)(P<0.05), which decreased by 16.81%~18.40% and 32.42%~36.63%, respectively. The lower HI and EGL were beneficial to maintain the postprandial blood glucose stabilization and reduce the glycemic load.