rice optimized for sake brewing. Ise Nishiki developed in 1860, Omachi (:ja:雄町) developed in 1866 and Shinriki developed in 1877 are the earliest representative varieties. In 1923, Yamada Nishiki, later called the "king of sake rice," was produced. Among more than 123 varieties of sake rice as of 2019, Yamada Nishiki ranks first in production and Omachi fourth. The government opened the sake-brewing research institute in 1904, and in 1907 the first government-run sake-tasting competition was held. In 1904, the National Brewing Laboratory developed yamahai, a new method of making starter mash, and in 1910, a further improvement, sokujō, was developed. Yeast strains specifically selected for their brewing properties were isolated, and enamel-coated steel tanks arrived. The government started hailing the use of enamel tanks as easy to clean, lasting forever, and devoid of bacterial problems. (The government considered wooden tubs (:ja:桶) to be unhygienic because of the potential bacteria living in the wood.) Although these things are true, the government also wanted more tax money from breweries, as using wooden tubs means a significant amount of sake is lost to evaporation (approximately 3%), which could have otherwise been taxed. This was the temporary end of the wooden-tubs age of sake, and the use of wooden tubs in brewing was temporarily eliminated. In Japan, sake has long been taxed by the national government. In 1878, the liquor tax accounted for 12.3% of the national tax revenue, excluding local taxes, and in 1888 it was 26.4%, and in 1899 it was 38.8%, finally surpassing the land tax of 35.6%. In 1899, the government banned home brewing in anticipation of financial pressure from the First Sino-Japanese War and in preparation for the Russo-Japanese War. Since home-brewed sake is tax-free, the logic was that by banning the home-brewing of sake, sales would increase, and more tax revenue would be collected. This was the end of home-brewed sake. The Meiji government adopted a system in which taxes were collected when sake was finished, instead of levying taxes on the amount and price of sake at the time of sale to ensure more revenue from liquor taxes. The liquor tax for the sake produced in a given year had to be paid to the government during that fiscal year, so the breweries tried to make money by selling the sake as soon as possible. This destroyed the market for aged , which had been popular