Decaffeination - Decaffeinated Tea

Decaffeinated Tea

Tea may also be decaffeinated, usually by using processes analogous to the Direct Method or the CO₂ process, as described above. Fermentation i.e., the process of oxidizing tea leaves to create black tea ("red" in Chinese tea culture) or oolong tea leaves from green leaves, does not affect the amount of caffeine in the tea, though tea-plant species (i.e., Camellia sinensis sinensis vs. Camellia sinensis assamica) may differ in natural caffeine content. Younger leaves and buds contain more caffeine per weight than older leaves and stems. Also, certain processes during production might lend a hand in either decreasing the caffeine content directly or simply lowering the rate at which it is released throughout each infusion. Several instances in China where this is evident is in many cooked pu-erh teas, as well as more heavily fired Wuyi Mountain oolongs; commonly referred to as 'zhonghuo' (mid-fired) or 'zuhuo' (high-fired). A generally accepted statistic is that a cup of black (red) tea contains 40–50 mg of caffeine, roughly half the content of a cup of coffee. Although a common technique of discarding a short (30– to 60-second) steep is believed to reduce caffeine content in a subsequent brew by 80–90%, research suggests that a five-minute steep yields up to 70% of the caffeine, and a second steep has one-third the caffeine of the first (about 23% of the total caffeine in the leaves).