GABA

GABA is not a cultivar or a region but a method: the fresh leaf is processed in a nitrogen atmosphere, without oxygen, and naturally accumulates γ-aminobutyric acid (GABA). Applied mostly to Taiwanese oolongs, it yields a notably smooth cup, low in astringency, with a sweet, fruity profile. The technique emerged in Japan in the 1980s and is now a segment of its own.