The production process of sweet potato vermicelli

In China, vermicelli can be found almost everywhere in the country. Due to different production locations, the thickness of vermicelli varies slightly from region to region. Vermicelli is mostly made from sweet potato flour. Many people want to know the production process of sweet potato vermicelli. You must choose good sweet potatoes before making vermicelli, otherwise it will affect the taste and quality of the vermicelli. The following article introduces the detailed production process of sweet potato vermicelli. Let’s take a look.

Process

Raw material processing → crushing → filtering → drying → making paste → filtering → cooling → drying → finished product.

2. Production method

(1) Select potatoes. Choose sweet potatoes with smooth surfaces, no pests or diseases, no green heads, and of moderate size, and discard the small ones and keep the large ones.

(2) Cleaning. Put the selected sweet potatoes into a basket and place it in water. Wash away dirt and impurities. Trim off the ends and surface roots.

(3) Crushing. The selected sweet potatoes should be chopped with a grinder in time and then ground into slurry. When beating the pulp, water should be added while grinding. The finer the grinding, the better, so that the starch granules in the cells can be ground out as much as possible to increase the flour yield.

(4) Filter. The purpose is to separate the skin residue from the starch. Generally, 2-5 feet of hanging pulp cloth is used as filter bag for filtration, and it is filtered twice in total. The first slurry should be thinner, the second time thicker. The filtrate is then sent to a sedimentation tank (the skin residue can be used as feed). After being placed in the pond and left to stand for two days, the supernatant in the pond was discharged. Add 1/3 of the original amount of water, stir, and filter again. This time the filtrate enters a small pool and is left to settle.

(5) Expose starch to the sun. When the water in the pool is no longer turbid, that is, completely clear, drain the supernatant. Discard the oil powder on the surface of the starch precipitation layer, take out the starch in the lower layer, hang it into a powder ball (i.e. dough), and move it to the drying yard for exposure. When half of the water in the powder ball evaporates, cut the powder ball into several pieces and expose them to the sun. The drying yard is set up in a sunny place sheltered from the wind to prevent dust pollution.

(6) Make paste. This process is the key to determining the quality of vermicelli. Add 25 grams of alum for every 500 grams of starch, stir with 2.5-3 kilograms of cold water, put into a large pot and boil, stirring constantly, until it reaches 80%-90% maturity (forming gelatinized starch). The beaten paste can be added to other starches and stirred into a moderately soft dough.

(7) Wire leakage and cooling. Before straining the silk, prepare two pots (model 8), two cold water tanks and a medium-sized 48-hole strainer. Because sweet potato vermicelli is thicker, the holes in the colander should be slightly larger than those of other vermicelli colanders. When leaking the silk, the paste should be fully stirred and evenly added with warm water while stirring. The water temperature should be around 50°C. Grab a ball of batter and let it fall naturally. If it does not break, it means it is of appropriate consistency and you can start to thread it. Prepare a pot of boiling water and continuously add it into the colander. When the water in the colander is almost boiling (97-98°C), let the dough flow down through the holes of the colander, gradually lengthening and becoming thinner to become vermicelli (if conditions permit, it is best to use a vermicelli machine). After the vermicelli sinks to the bottom of the pot and becomes gelatinous, when it floats to the surface, it is immediately fished out and placed in a cold water tank to cool down. Then it is arranged into bundles by hand and put on a wooden rack. It is then passed through another cold water tank to cool again, and is constantly shaken until the vermicelli becomes loose strips. It is then placed indoors and taken out to dry outdoors after it has cooled completely.

(8) Drying silk. Take the fans to a sunny location sheltered from the wind and hang them up to dry in the sun. After drying, it can be sorted and packaged into finished products.

3. Finished product quality requirements

The vermicelli is of uniform thickness, consistent color, dry and transparent, has good toughness and is not easy to break.