I visited Ishii Miso Brewery in Matsumoto. It was founded in 1868 (the end of the Edo era) and is still producing miso by a unique traditional natural method.
Miso, soybean paste, is an essential ingredient in Japanese cuisine. We have miso soup every day and sometimes use it for other dishes. Miso is fermented food so it is very healthy.
Nagano Prefecture is the top producer of miso (46%) in Japan. There are many miso breweries in Nagano and some of them have their own shop.
Especially in Ishii Miso Brewery, you can see inside the brewery and have a lunch containing miso soup, salad with miso dressing, rice balls, and even ice cream using their miso.
Miso used to be made in homes. But now, many Japanese don't know or find out how to make miso.
A special point of this brewery is that they ferment miso over three years. Normal cheap mass-produced miso is fermented only a few months in a factory. Their 3 year miso's taste is much deeper and yummier than normal miso.
They use wooden barrels to ferment miso, which is also unique. Normally the barrels are plastic or metal, but wooden barrels enable air to permeate so they are good for fermentation.
Ishii Miso is located a 15-minute walk from Matsumoto Station and near the Matsumoto Museum of Art. It also has a large parking lot that enables even a big tour bus to park. Many foreigners visit this brewery even though it does not appear in guide books and there is no English website. If you visit the famous Matsumoto Castle, I recommend you to visit Ishii Miso, too. Also, visiting Matsumoto Museum of Art to see Kusama Yayoi's art and stopping by Matsumoto Art Performing Centre building designed by the famous architect Toyo Ito are nice options.