Of utmost importance, severe shading helps create more umami flavor—a taste unique to Japan—as the plant stores additional L-theanine in the leaf. L-theanine is an amino acid that mostly develops in the roots of the tea plant. As it moves into the tea leaves, it reduces back to the previous components, which, when exposed to sunlight, help form catechins. Shading, therefore, prevents the creation of catechins that can give tea an astringent or bitter taste.
Discovered in 1949 in Japan, L-theanine is rarely seen in nature except in tea. It enhances mood by stimulating alpha brainwaves, which can induce a calmer, yet more alert, state of mind. L-theanine also helps lower the pulse rate and blood pressure while it balances and moderates the effects of caffeine, making shade-grown green tea all the more unique in the world of healthy beverages.
While most Japanese teas are mechanically harvested, Master Sakamoto continues to hand pluck the leaves that go into making his best tea grades. Throughout the short growing season, he is a busy man on a mission to keep ancient traditions alive. Unlike his tea plants, he has little time to rest in the shade.