Black rice is a processed product of black rice, which belongs to glutinous rice and is a characteristic variety formed by long-term cultivation of Gramineae rice. The appearance of rice grains is oblong, and the rice husk is grayish brown. Grain types are indica rice and japonica rice, and grain quality is divided into waxy and non-waxy. Brown rice is black or dark brown, which is rich in nutrition and has high edible and medicinal value. In addition to cooking porridge, it can also make all kinds of nutritious food and wine, which is known as "black pearl" and "king of rice in the world". Black rice in Yangxian County, Shaanxi Province is the most representative, and it has been called "medicinal rice", "Gong Mi" and "longevity rice" since ancient times.