Enameled tanks account for by far the largest share in modern sake breweries. It is said that it was not until the late 1950s at the time of Japan’s economic boom when enameled tanks began to be used for sake brewing.
Having focused on the convenience and safety of enamel and aimed for using it for sake brewing, K.K. Nada Horo Tank Seisakujo was established. It proposed enameled tanks to sake breweries in Nada area, Kobe, but they hesitated to use the tanks. However, when the company asked one of sake breweries in Niigata, which the company had known well, for advice on the tanks, several of them showed interest in them and started using them.
Compared to kioke wooden barrels, which had been used for centuries, enameled tanks had many advantages; easy to control the microbe motility, easy to take care of and capable of mass-producing homogenized sake. So the reputation of tanks spread instantly among sake breweries. Since a higher tax rate was imposed on sake, the advantage that enameled tanks can prevent sake from being evaporated naturally in kiokes also accelerated the use.
On the other hand, the National Institute for Brewing Studies played a key role to contribute to the research of yeast and succeeded in the cultivation of best yeast fungus, which spread among sake breweries around Japan. We can say that such widely-spread ginjoshu owes much to enameled tanks that can exclude bacteria but only keep the necessary ones.