Burn sweet potato powder with a lighter. If the sweet potato powder has white swelling and no peculiar smell after burning, it means that this sweet potato powder is pure sweet potato powder. If the sweet potato powder has a black powder after burning and has an odor, it means that the sweet potato powder is inferior.

Vermicelli is a kind of traditional food, which is made of sweet potato and potato. By grinding and precipitation. All parts of China have their own unique production technology. The finished vermicelli is grayish white, yellow or yellowish brown, which can be divided into round vermicelli, fine vermicelli and wide vermicelli according to its shape.

The cooked vermicelli tastes smooth and elastic, and can be made into delicious food with vegetables, pork and chicken.

Vermicelli is a filamentous or strip-shaped dry starch product made from rice, beans, potatoes and miscellaneous grains. The processing of vermicelli has a history of more than 1000 years in China, and it is produced everywhere. It is grayish white, yellow or brown, and it is a dry product. There used to be a saying that "vermicelli can't be made without alum". In recent years, this tradition has finally been broken through continuous research and development by experts.

Vacuum vermicelli can be produced by vacuum treatment without using or using a small amount of alum-free food additive strength source; Self-cooked vermicelli and steamed vermicelli also have an alum substitute-Jinliyuan, which reaches the national standard of truly alum-free vermicelli. Safe and legal alum-free vermicelli will be the development direction of vermicelli industry.