GABA Oolong
GABA oolong is a modern oolong processed under nitrogen instead of oxygen, which converts the leaf's glutamic acid into gamma-aminobutyric acid (GABA), the compound it is named and marketed for. The anaerobic step also reshapes the flavor, pushing toward a distinctive tangy, dried-fruit, caramel-and-sour-cherry character quite unlike a conventional oolong. To carry the name it must contain at least 150 mg of GABA per 100 g.
Usually a rolled, semiball oolong similar in appearance to other Taiwanese oolongs; the giveaway is in the cup, a tangy, sour-sweet, dried-fruit and caramel profile rather than clean florals. A stated GABA content (the 150 mg per 100 g threshold or higher) on the label indicates genuine anaerobic processing. The distinctive tangy note is intrinsic to the method, so a completely conventional oolong flavor suggests the GABA processing was minimal.
The nitrogen-processing technique was developed by Japanese researchers in the late 1980s and was adopted and popularized in Taiwan, now the main source of GABA oolong. It is a processing category rather than a region or cultivar, so it can be made from various oolong base leaves at different oxidation and roast levels. The health framing, GABA as a relaxation and blood-pressure aid, drives much of its marketing.
Gongfu: 6-7 g per 100 ml, 95-100°C, 30-45 seconds ascending, 6-8 infusions. Western: 4 g per 250 ml, 95°C, 2-3 minutes. Brewed like any rolled oolong, with the tangy character most pronounced in the early steeps.
GABA oolong runs €15-40 (about $16-43) per 100 g, with premium high-mountain or carefully made lots reaching €40-70 (about $43-76) per 100 g.
Prices reviewed June 2026
GABA tea was discovered as a byproduct of research into food preservation under nitrogen, when scientists found the anaerobic treatment dramatically raised the leaf's gamma-aminobutyric acid content. The 150 mg per 100 g figure is the conventional minimum used to label a tea as GABA, and the actual content varies considerably between producers.
The steps overlap in practice; this is a reading order, not a set of separate stages.
Ali Shan
A conventional high-mountain oolong, useful for tasting exactly what the anaerobic processing changes.
Dong Ding
A roasted oolong, another route by which the base leaf is transformed after picking.
Oriental Beauty
Another oolong defined by an unusual transformation, insect bites rather than nitrogen processing.