How many times should a cup of tea be steeped?
Some people in life like to repeatedly steep tea leaves until there is no flavor left; others change the tea leaves after one or two steepings. Which of these two practices is correct, and how many times is it best to steep a cup of tea? From a nutritional absorption standpoint, bagged tea is best steeped only once, while loose-leaf tea should not be steeped more than three times.
Tea leaves contain tea polyphenols, which have anti-cancer properties; tea polysaccharides, which can lower blood sugar; caffeine, which stimulates the central nervous system; as well as various other nutrients such as amino acids and vitamins. The amount of these nutrients that can be extracted is closely related to the number of steepings. Generally speaking, the larger the particle size of the tea leaves, the slower the nutrients are extracted; the smaller the particle size, the faster the extraction.
Compared to loose-leaf tea, the tea in bagged tea is cut and rolled during processing, which thoroughly breaks down the leaf cells, resulting in a smaller particle size. As a result, 80% to 90% of the nutrients in bagged tea are extracted during the first 3-5 minute steeping. After the second steeping, the remaining 10% of nutrients is almost completely extracted. Therefore, it is recommended that bagged tea be steeped only once, as there is little loss of nutritional absorption and it does not affect the taste. Due to their larger particle size, loose-leaf tea should be steeped for a longer time for the first steeping, ideally around 5 minutes, during which 60% to 80% of the nutrients will be extracted. After the second steeping, 80% to 90% of the nutrients will have been extracted. After the third steeping, the nutrient extraction rate will exceed 95%, and further steeping will provide no nutritional benefit.