Beijing Yongfeng brand export small square bottle 50% pure grain wine. According to relevant information, Yongfeng brand Beijing Erguotou light-flavor liquor (exported in small square bottles) and Yongfeng Erguotou coffee are labeled as 50% pure grain liquor, so they are pure grain liquor. Pure grain wine is a kind of wine brewed entirely from grains. The main style characteristics of grain wine depend on the following aspects: first, koji-making technology, second, brewing technology, third, laojiao mud technology, and fourth, blending technology.