REAL Kombucha REAL Brut is part of the brand's Small-Batch Collection, a higher-specification sub-range of REAL Kombucha's AF sparkling teas. It is brewed from Tie Guan Yin oolong, a variety grown in Anxi County, Fujian, China, known locally as the Iron Goddess of Mercy. The fermentation includes grape seed and takes place over oak. Production is at the Fermentery on the Waddesdon Estate in Buckinghamshire.