Chinese green tea boasts a variety of categories, a long history and enjoys great popularity among customers. Aroma is one of the key indicators for evaluating the quality and flavour of green tea and storage plays a crucial role in affecting the aroma and flavour of green tea. The study summarizes and analyzes the impact of factors such as storage duration, environmental temperature, and oxygen on the aroma compounds of green tea during storage. Furthermore, it sorted out the markers of “stale odor” in stored green tea. This research aims to provide a reference for the maintenance of green tea storage quality and flavor as well as improving processing technolog.

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.

High-salt diet is well recognized as a risk factor for hypertension, and dietary intervention plays a critical role in the prevention of hypertension. The current study investigated the effects of selenium-enriched green tea (Se-GT) and ordinary green tea (GT) on prevention of hypertension of rats induced by high-salt diet, as well as their potential regulatory and mechanism. Our results showed that GT and Se-GT supplementations significantly prevented the increase of blood pressure (BP), activated the phosphoinosmde-3-kinase/protein kinase B (PI3K/Akt) signaling pathway, and regulated the gene expression related to BP, as well as improved the tissue damage like heart, liver, and kidneys. Besides, the key parameters associated with oxidative stress, inflammation and endothelial dysfunction were also altered by GT and Se-GT treatments. Importantly, GT or Se-GT administration adjusted the diversity and composition of the intestinal flora. Moreover, GT and Se-GT supplementations increased the abundance of beneficial bacteria and reduced the abundance of harmful or conditional pathogenic bacteria. More specifically, GT intake specifically and significantly enriched the relative abundance of Paraprevotella and Bacteroides, whereas Se-GT was characterized by specific and significant enrichment for Allobaculum and Bifidobacterium. Our results proved that dietary supplement of GT and Se-GT remarkably improved the vascular functions and effectively prevented tissue damage by regulation of intestinal flora, and thus preventing hypertension induced by high-salt diet.