Caffeine in green tea are in general said to be one third of coffee. Caffeine in green tea is said to provide the bitter flavor. This caffeine in green tea will depend on when it was picked. Younger spring green teas are said to contain more caffeine, so high end Japanese green teas such as matcha and gyokuro will contain more caffeine.
Japanese green tea is about 1/3rd of caffeine compared to coffee and slightly less than black tea.
*Source: Ministry of Education, Culture, Sports, Science and Technology(JAPAN) “STANDARD TABLES OF FOOD COMPOSITION IN JAPAN”
The very well known premium tea leaves, Gyokuro will have the most amount with 160mg. Next will be the matcha green tea containing 30 mg relatively very low. Sencha and Houjicha will have 20 mg and genmaicha will have the least caffeine with 10mg.
|Type of Japanese Green Tea||Amount of Caffeine (in 100g)|
Source: Ministry of Education, Culture, Sports, Science and Technology of JAPAN
The amount of caffeine that will be in your tea will depend on how you brew the tea, so please use the chart above for reference. As for Japanese green tea, it will be better to brew it at a shorter time to avoid many caffeine to be extracted. The longer you brew basically the more you get the caffeine.
If there are any questions please feel free to ask anytime.