Black: refers to food that is grayish black or close to black. Cereals: refers to rice, wheat, soybeans, corn and sweet potatoes. Especially grain. Then "black particles" refer to: black fungus, black sesame powder, black beans, black beans and black dates, and black sesame is the black seed of sesame in the flax family.
Other sayings of whole grains
Cereals refer to rice, wheat, soybeans, corn and potatoes. It is customary to refer to grains other than rice as grains, and grains also refer to food crops in general. Therefore, it is generally believed that grain is the general term for food crops. In Huangdi Neijing, cereals are considered as "japonica rice, adzuki bean, wheat, soybean and millet".
In Teng Wengong by Mencius, the five grains are called "rice, millet, wheat and glutinous rice", and in Buddhist sacrifices, they are also called "barley, wheat, rice, red beans and flax". Then Li Shizhen recorded in Compendium of Materia Medica that there are 33 kinds of cereals and 47 kinds of beans 14. There is also a saying that grains generally refer to five crops, namely "hanging, rattan, root, horn and ear"