Three to four yuan a catty.

The price of sweet potato vermicelli fluctuates between 7 yuan and 30 yuan, and there are so many links in the middle. Pure sweet potato vermicelli costs 8- 1 kg and 40 yuan vermicelli costs 1 kg, which is a city with rich sweet potato production. Vermicelli is a kind of filamentous food made of mung bean and sweet potato starch, so it is named vermicelli. Often called vermicelli and winter noodles (mainly in Taiwan Province), the Korean peninsula is called Tang noodles, and Vietnamese noodles are called noodles. The best vermicelli is made of mung bean, corn starch or sweet potato starch, but the quality is not as good as mung bean vermicelli, because mung bean has the most amylose, which is not easy to rot when cooked and tastes the most greasy. Similar to spaghetti, it is sold after drying. Before eating, it is best to soak it in water to make it soft. The diameter of vermicelli is generally about 0.5 mm, which is why it has the name of "silk".