Iio Jozo is a small, artisanal brewery in northern Kyoto Prefecture, established in 1893 in Miyazu on the sea-shore. Akihirio Iio is now the fifth generation of his family to run the vinegar house, using organic grown unpolished brown rice from its own local farmers. The quality of Iio Jozo’s rice vinegars comes from a technique perfected by his father, Hiroaki. He fortified the brewery’s homemade sake with more rice to brew pure, rich full-bodied Junmai sake that included equal parts of sake, water, and existing vinegar. It is then fermented for 100 days, then aged for 8 months under a wooden and straw mat. By creating a double-brewed type of rice vinegar, Iio Jozo develop more complex vinegar aromas, contain more healthy nutrients and taste more umami. As a result, the black-labeled Genmai Kurosu contains the equivalent of 200 grams of rice per liter, compared to the commercially produced equivalent of 40 grams of rice per liter.