不同加工方式对体外模拟胃肠消化黑青稞酚类物质含量及抗氧化活性的影响

为探究不同加工方式制备的黑青稞经体外模拟胃肠消化后酚类物质及抗氧化活性的变化规律，采用蒸煮、炒制、挤压膨化、气流膨化、发酵方式处理黑青稞，并测定体外模拟胃肠道消化后其酚类物质组成、含量及抗氧化活性。结果表明，与未消化样品相比，5 种加工黑青稞经胃肠消化后多酚含量均显著提高（P＜0.05），为未消化样品的1.99～2.44 倍。除气流膨化外，其他4 种加工黑青稞经胃肠消化后总黄酮含量均较未消化样品显著降低（P＜0.05），为未消化样品的34%～70%。经体外模拟消化后，5 种加工黑青稞中根皮素、原儿茶酸、对香豆酸和阿魏酸是主要酚酸类物质，儿茶素是主要的黄酮类物质；与未消化样品相比，5 种加工黑青稞主要酚酸类单体物质含量均显著提高（P＜0.05），黄酮类单体物质含量均显著降低（P＜0.05）。抗氧化活性综合指数分析结果显示，5 种加工黑青稞的抗氧化活性由强到弱依次为挤压膨化黑青稞（89.61%）＞发酵黑青稞（88.16%）＞蒸煮黑青稞（77.67%）＞气流膨化黑青稞（76.86%）＞炒制黑青稞（75.13%）。综上，气流膨化处理黑青稞的总酚、总黄酮含量最高，而挤压膨化处理黑青稞抗氧化活性最高，该研究结果可为不同需求青稞产品加工方式的选择提供科学指导。

Effects of Different Processing Methods on Phenolic Content and Antioxidant Activity of Black Hulless Barley in Vitro Gastrointestinal Digestion

This study aimed to explore the changes in the phenolic content and antioxidant activity of black hulless barley processed by different methods after in vitro gastrointestinal digestion. The tested methods included boiling, stir frying, extrusion puffing, explosion puffing and fermentation. After digestion, the phenolic content of the five processed samples increased 1.99–2.44 folds (P < 0.05). The total flavonoid content of all processed samples except the one subjected to explosion puffing decreased by 34%–70% (P < 0.05). Phloretin, protocatechin, p-coumaric acid and ferulic acid were the major phenolic acids, and catechins were the major flavonoids after in vitro gastrointestinal digestion. Meanwhile, the contents of the major monomeric phenolic acids in the five processed samples significantly increased (P < 0.05), whereas the contents of the monomeric flavonoids significantly declined (P < 0.05). The antioxidant potency composite (APC) indexes of the processed samples declined in the following order: extrusion puffing (89.61%), fermentation (88.16%), boiling (77.67%), explosion puffing (76.86%) and stir frying (75.13%). In conclusion, the contents of total phenols and total flavonoids were the highest in black hulless barley subjected to explosion puffing, while the sample subjected to extrusion puffing had the highest antioxidant activity. This study can provide a scientific guideline for selecting different processing methods for the development of hulless barley products to meet diverse consumer demands.