Since ancient times, people have been accustomed to brewing tea with hot water, believing that only hot water can extract the flavor and beneficial components of tea leaves. In fact, cold water brewing is just as effective. With enough patience, the fragrance and nutrients of the tea will slowly seep out from within.

Cold water brewing refers to steeping tea leaves in cool boiled water or mineral water. Office workers, drivers, hikers, and others can enjoy this delicious and healthcare-beneficial "cold-brewed tea" anytime, anywhere, as long as they can buy mineral water. Research shows that after 2 hours of cold brewing, the extraction of water-soluble components such as tannins and free catechins from the tea leaves exceeds that of hot-brewed tea. After 8 hours of cold brewing, the extraction of water-insoluble components like esterified catechins can reach about 70% of that in hot-brewed tea.

Furthermore, studies have found that tea contains a polysaccharide substance that both promotes insulin production and removes excess sugar from the blood. However, this polysaccharide is heat-sensitive and would be severely damaged if brewed with hot water, whereas cold brewing avoids this issue. From this perspective, drinking "cold-brewed tea" can help people control their blood sugar levels.