Soymilk (豆浆, doujiang) originated in China, probably during the early Han dynasty (202 BCE to 9 CE), after the rotary millstone was introduced and became widely used to grind wheat.[1]:51–52 It did not become widely used in China until the 1800s, when it was discovered that extended heating made it taste better and easier to digest.[1]:52
Soymilk was introduced to the US market by Vitasoy in 1979; the first domestic manufacturer of soymilk was Sunrich Food Group, which introduced its products in 1985.[2]