Mild sour and mellow taste Far Infrared roasted Tsubo (Urn) Finish Zen-koji Omugi Kurozu Barely Black Vinegar fully fermented by Koji (Aspergillus oryzae) Black Vinegar developed for mild sour and mellow taste to drink for health. It contains methionine of a sulfur-containing amino acid and rich glutamic acid of umami.