Mung bean is a plant of the legume family and the subfamily Cowpea, native to India and Myanmar, and has been cultivated in China for more than 2,000 years. The color of mung bean seed coat mainly includes three categories: green, yellow-green, and dark green. The seed coat is divided into two types: glossy (bright green) and dull (dark green). Those with dark green and lustrous color, large and neat grains, round shape, and easy to boil are the best quality. Mung bean is a traditional bean food of the Chinese people. It is rich in various vitamins, calcium, phosphorus, iron and other minerals than japonica rice. Because of its rich nutrients, it can be used as porridge, bean rice, bean wine or Erdun cakes, etc., so it is known as "a good food and a good grain".