1. Choose potatoes. Choose sweet potatoes with smooth surface, no pests and diseases, no green heads and moderate size.

2. Cleaning: put the selected sweet potatoes into a laundry basket and water, wash away dirt and impurities, and cut off both ends of the sweet potatoes.

Smash. The washed sweet potatoes should be crushed in time. Use 380 or 440 pulverizer driven by 195 12 horsepower diesel engine, and add water while beating. The finer the beating, the better, and improve the powder yield.

Filter. Filter with 0.7 ~ 1.5m hanging cloth and filter twice. The initial solution is thinner and the second solution is thicker. Two days after the filtrate enters the tank, drain the water in the tank, add 1/3 raw water, stir, filter again, and deposit the filtrate in a small tank.

5. Exposure: after the tank body is completely clarified, drain the water, take out the surface oil powder, take out the lower starch, hang it into a powder pile, and expose it to the threshing floor. When half of the water in the powder pile evaporates, cut the powder pile into several parts and expose it to the sun. The threshing floor is located in the leeward and sunny place to prevent dust pollution.

Step 6 paste. Add100g of alum to 500g of starch, mix 2500 ~ 3000g of cold water, and put into a basin. Put the pot into the pot and bring it to a boil, stirring constantly until it is 80% to 90% mature. The paste can be used for 20 kilograms of vermicelli.

7. Silk leakage. You can try it before it leaks to see if the dough is suitable. If the leaked vermicelli is neither coarse nor fine, it is appropriate. The following strips are too fast and broken, indicating that the starch paste is too thin, so it should be mixed and rubbed with dry starch to make the surface toughness moderate; It is difficult or too slow below, the thickness is uneven, the surface starch is too dry, and some wet starch should be added. It is advisable to mix powder once before silk leakage. The temperature of the dough is preferably 30~42 degrees Celsius. Prepare 2 pots (model 8), 2 cold water tanks and a medium-sized 48-hole colander. In case of silk leakage, the paste should be stirred evenly, and warm water should be added while stirring at a temperature of 50℃. When the starch ball leaves your hand, grab a ball (handle) and let it fall naturally. If you keep falling, you will leak silk. When silk leaks, prepare a pot of boiling water. Only when the water in the pot is boiled will silk leak. When the silk strips sink to the bottom of the pot and float out of the water, they can be taken out of the pot, cooled once in a cold water tank, tied into bundles by hand and put on sticks, cooled in another cold water tank, and kept swinging until the sector is loose. Then put it indoors, let it cool completely, and then take it out to dry.

8. Dry the silk. Take the vermicelli to the leeward and sunny place, dry it, and package it to get the finished product.

I hope it helps you.