Comparison of chemical profiles, dissolution patterns, sensory evaluation and bioactivity of selenium-enriched green tea and black tea: Influence of brewing conditions

Selenium (Se)-enriched tea has gained growing global popularity due to its superior health benefits compared to normal tea. The sensory quality and health attributes of tea soup are determined by the dissolution patterns of selenium-enriched teas. This study compared the chemical profiles of selenium-enriched black tea (SeBT), selenium-enriched green tea (SeGT), normal black tea (BT), and normal green tea (GT). The dissolution patterns and sensory evaluation of SeGT and SeBT were investigated under different brewing conditions. Through establishing a daily tea drinking model, the antioxidant activity, hypoglycemic activity, and antibacterial activity of tea soup before and after simulated digestion were determined. In comparison, SeGT exhibited rapid dissolution of chemical components but was prone to bitterness in the tea infusion, which was best brewed at 100 °C for 5-7 min to optimize functional component release while avoiding bitterness, demonstrating stronger antioxidant, hypoglycemic and antibacterial potential. Meanwhile, SeBT showed a slower release rate of chemical components but greater stability across brewing conditions, which was well-suited for brewing at 85 °C or 100 °C for 3-7 min, with its inherent sweetness and mild flavor appealing to a broader consumer base. This study evaluated the quality of different selenium-enriched teas, explored the dissolution patterns, sensory evaluation, and in vitro bioactivities of tea soup, providing guidance for consumers in selecting optimal brewing conditions for different selenium-enriched teas that combine flavor and nutritional characteristics.