Visiting Tokyo’s Edogawa Ward, we toured Ogawa Sangyo, one of only two factories that still produce mugicha in the capital. The guide, president Keisuke Ogawa, explained that barley tea contains no tea leaves—just roasted barley infused hot or cold. Domestic barley from Ibaraki, Tochigi and Toyama supplies the plant, a choice that grows costlier as Japan’s growers shrink, maintaining a traditional profile that appeals to nostalgic consumers.

Ogawa Sangyo favors a labor‑intensive direct-fire roasting method over common convection ovens. Grains tumble with sand, allowing infrared heat to reach the core evenly. The first minute at 250 °C yields a light‑brown, popcorn‑like aroma; a second minute at 180 °C deepens color and expands the kernels, creating a twice‑roasted product prized for its richer flavor. This control boosts the brand’s reputation among tea fans.

After cooling, the grains are bagged at 50 bags per minute into triangular or rectangular sachets. The company claims triangular bags let water circulate better, extracting more nuance. Packaging remains manual, and the factory’s interior stays roughly 10 °C hotter than outside during roasting. Explains its enduring popularity nationwide.