Caffeine Across Tea Types: Why Gyokuro Leads
Caffeine accounts for 2 to 4 percent of dry tea leaf weight. How much reaches your cup varies considerably by type and preparation.
Per 100 ml of brewed liquid, Japanese composition data gives:
| Drink | Caffeine |
|---|---|
| Coffee | 60 mg |
| Instant coffee | 57 mg |
| Black tea | 30 mg |
| Sencha | 20 mg |
| Hojicha | 20 mg |
| Oolong | 20 mg |
| Genmaicha | 10 mg |
Among brewed teas, gyokuro stands out well above the rest.
Why gyokuro is high
Cultivation and preparation both contribute.
Gyokuro is shade-grown — covers block sunlight while new shoots develop. The purpose is preserving L-theanine, which converts to astringent catechins under light, but caffeine also declines less under shade.
Gyokuro uses young shoots, and younger tissue carries more caffeine.
Preparation compounds it: gyokuro is brewed with little water for a concentrated result.
Matcha is measured differently
Matcha comes from the same shade-grown tencha, but you consume the ground leaf rather than an infusion.
Reference figures quote roughly 48 mg for 1.5 g of matcha in 70 ml of water — per serving, not per volume, because the amount depends on how much powder you used rather than how you brewed it.
Brewed teas vary with technique
Higher temperature and longer steeping extract more caffeine. The same leaf produces different cups.
Brewing gyokuro at a lower temperature is a deliberate way to favor umami over bitterness and astringency.
Teas without caffeine
Barley tea, buckwheat tea, black bean tea, and rooibos contain none — they are not made from the tea plant.
Hojicha, bancha, black tea, and oolong all are, so caffeine is present regardless of processing. Hojicha is often called low-caffeine; it is lower, not free of it.
