For many years, Japanese people had enjoyed drinking the warm water left over after soaking kombu kelp. Nearly 100 years ago, Gyokuroen wanted to turn that by product into a commercial drink, so they developed kombucha - an instant hot drink made from powdered kombu kelp, which had the same gentle flavor as the traditional drink Japanese people had enjoyed for years.

Since then, Gyokuroen have continued to develop the taste of their instant kombucha powders, and have branched into making other forms of savory, umami tea, such as shiitake mushroom tea.