What is the main component of grain?

Grain refers to all kinds of plant seeds in cooked food, also known as "five grains", which are rich in nutrition, mainly protein, vitamins, dietary fiber, fat and so on. The food concept of FAO refers to grains, including wheat, beans, coarse grains and rice, such as:

1. Wheat: wheat, barley, highland barley, rye and oats.

2, beans: soybeans, red beans, mung beans.

3. Rice: japonica rice, indica rice, glutinous rice, upland rice and deep rice.

4. Coarse grains: corn, sorghum, buckwheat, millet and millet.