Brewing characteristics, physicochemical constituents, and antioxidant activity of the infusions of colored highland barley roasted at different times

Colored highland barley (CHB) contains various bioactive constituents and thus has excellent potential for roasting into functional beverages. This study aimed to investigate the differences in brewing characteristics, physicochemical components, and antioxidant activities of the infusions of CHB roasted at 6.0 min, 9.0 min, and 12.0 min. The roasted CHB (RCHB) components were primarily leaching after three steeping times, with the highest persistence of the roasted black cultivar during brewing. Roasting treatment of CHB endowed characteristic aromas and taste to their infusions, and the roasted white cultivar infusions showed relatively higher sensory quality scores. The infusions brewed with CHB roasted at 6.0 min generally revealed higher releases of β-glucan and lower antioxidant activities, whereas 9.0 min and 12.0 min roasting of CHB were beneficial for leaching total sugar, protein, polyphenols, flavonoids, and free amino acids in their infusions, among which polysaccharides and polyphenols might contribute to their elevated antioxidant activities. Furthermore, the antioxidant activities of the infusions brewed with white and black cultivars were susceptible to roasting, resulting in apparent increases and decreases in their abilities, respectively. These results suggested that the RCHB infusions were potential candidates for cereal beverages and functional foods.