不同熟化方式对青稞淀粉体外消化及多酚利用特性的影响

以青稞粉为研究对象，结合体外模拟消化，探究挤压和煮制对青稞淀粉体外消化和多酚含量及抗氧化活性的影响。结果表明：不同处理显著提高了青稞粉的水解率，其中青稞挤压粉的水解率和预估血糖生成指数最高，抗性淀粉含量最低。不同处理均显著降低了未消化青稞粉中总酚、总黄酮含量和抗氧化活性，其中煮制处理分别降低了32.8%、30.5%、26.7%（FRAP法）和14.8%（TEAC法）。与模拟胃消化相比，模拟肠消化阶段显著提高了青稞粉总酚、总黄酮的释放量及其生物有效性，并主要集中在模拟肠消化的前30min；与未消化样品相比，模拟胃肠消化后，青稞粉自由基清除能力提高4倍左右。此外，消化后结果同样表明，煮制处理对青稞酚类物质和抗氧化活性的生物有效性破坏较大。

Effects of Different Cooking Methods on in Vitro Starch Digestion and Polyphenols Utilization Characteristics of Highland Barley

Taking highland barley flour as the research object, combined with in vitro simulated gastrointestinal digestion, to explore the effects of extrusion and steaming on the in vitro starch digestion, polyphenol content and antioxidant activity of highland barley. The results shown that hydrolysis rate of highland barley flour with different cooking treatments was significantly higher than that of raw highland barley flour, among which the highland barley extruded flour had the highest hydrolysis rate and estimated glycemic index, and the lowest resistant starch content. The content of soluble polyphenols, flavonoids and antioxidant activity of undigested highland barley flour were significantly reduced after different treatments, among which the steaming treatment decreased by 32.8%, 30.5%, 26.7% (FRAP) and 14.8% (TEAC), respectively. The release and bioavailability of total phenols and total flavonoids from the highland barley powder in simulated intestinal digestion was significantly higher than that in gastric digestion stage, and it was mainly concentrated in the first 30 min of simulated intestinal digestion. The free radical scavenging ability of highland barley powder after simulated gastrointestinal digestion was about 4 times higher than that of undigested samples. In addition, the post-digestion results also showed that the steaming treatment had greater damage to the bioavailability of the phenols and antioxidant activity of the highland barley powder.