Gaba tea is not a distinct type, but tea (usually oolong) that undergoes anaerobic fermentation in a nitrogen environment to become enriched with gamma-aminobutyric acid (GABA). It was developed in Japan and refined in Taiwan, where it acquired a balanced flavor. Thanks to GABA, the tea helps relieve stress, improve sleep, and boost concentration.
Single-origin tea in a 100 g tin. Read the full article in the encyclopedia.