Sweet potato and rice, processing can add value

Production technology of sweet potato starch

Wash the sweet potato, drain the water, break it into 2 cm pieces with a crusher, send it to a stone mill or electric grinder, add 3 to 3.5 times the water and grind it into starch pulp. The starch paste was poured into a sieve with a pore size of 60 mesh and the potato dregs were screened to get starch milk. Put the starch milk in the sedimentation tank for one night to make the starch precipitate at the bottom of the tank. Remove the supernatant, take out the crude starch, rinse and precipitate repeatedly with clean water to get the pure starch, and then dry, crush and sieve the starch to get the dry starch. This method is the traditional method of producing starch in rural areas without any machinery and equipment, and the processed starch can be used as the raw material for processing other starch foods.

If you need to produce sweet potato flour, you can invest 1.3 million yuan to purchase equipment, with an annual output of about 5000 tons.

Production method of sweet potato flour peel

Take the wet starch with a water content of 45% to 50%, slowly add it with 2.5 times the amount of starch, stir it gently with a stick, and add 0.3% alum. Take a small amount of paste with a powder spoon, put it in a rotating disk, float it into the boiling water in the pot, and move and rotate it with your hands to spread out the paste. When there is no white spot in the middle, take out the plate and cool it in clean water for a while, then peel off the formed powder and put it in clean water to cool. Soak the powder skin in the supernatant of precipitated starch for 3-5 minutes, then remove the powder skin and dry it with a bamboo curtain, and turn it over once to dry both sides evenly. When the moisture content is 16%-17%, the finished product will be finished.

This method is a traditional production method, which does not require a large amount of equipment investment, and the total investment is less than 20,000 yuan.

Sweet potato vermicelli processing

Take a certain amount of sweet potato dry starch. Place 4%-10% dry starch in a porcelain basin, add the same amount of water and stir well. Place the porcelain basin in a wooden basin filled with boiling water, add 4 times the amount of boiling water to the porcelain basin, and stir rapidly with a wooden stick to make the starch gelatinize into a thin paste. Put the mixing basin in a wooden basin containing 60 ℃ of hot water, then pour the remaining 90%-96% sweet potato starch into the mixing basin, then pour the mixed paste into the mixing basin and stir continuously until the starch is born. Fully knead it so that it becomes a semi-fluid state, then put it in a powder leakage ladle. Under the action of the shock force of the shock machine, the semi-fluid starch paste flows linearly from the small hole of the leaky ladle, falls into the boiling water pot, is cooked immediately and floats quickly on the surface of the water. Take out the vermicelli with a bamboo pole, soak it in cold water for a while, and then rinse it in the clarifying water poured out when the starch is precipitated. Then take out the fans and dry them in the sun.

This method is produced by local method, which requires pots, pots, leaking ladles, etc., and the total investment of the equipment is less than 10,000 yuan. If you want to carry out mechanized production, you need boilers, molding machinery, electromagnetic shock machines, rinsing pools, etc., with a minimum investment of 10 ~ 150000 yuan.

Processing of preserved sweet potato

Wash the fresh potatoes first and peel them off with a peeling machine or by hand. Cut the sweet potato into 2 cm × 2 cm × 5 cm French fries with a stainless steel knife. Add 1.5 times the water, 30% 40% sugar, 2% honey and 0.2% sulfite according to the weight of the French fries and boil them in a stainless steel pot. Take out the French fries together with the sugar solution, soak them in a large water tank for 24 hours, remove the French fries with a leaky ladle, place them in a bamboo sieve and dry them in a drying room of 50-60 ℃. The French fries are cooled and then packed in a polyethylene plastic bag.

The production equipment of this product is simple, only need stainless steel pot (less than 10,000 yuan), drying room (less than 10,000 yuan) and other auxiliary facilities (less than 10,000 yuan). If you need to expand production capacity, you only need to increase the production line.

Production technology of instant rice noodles

Wash the rice clean, and then soak the rice in clean water to make its water content reach about 40%. Soak for 7-8 hours in winter and 4-5 hours in summer. The rice is ground into pulp by stone mill or electric mill, the pulp concentration is controlled at 2530 Baume degrees (Baume is available in the market), and the fineness is all passed through the 80-mesh screen. The slurry is made into powder skin by powder skin production equipment. Then steaming the powder through the steamer, the temperature is 105 ℃, the time is 55 seconds. The steamed powder skin is quickly sent to the cooling room for cooling, and then sent to the pre-drying room for pre-drying. the highest temperature is 70-80 ℃ and the time is 15-20 minutes. Then cut into 1 mm wide noodles by hand or mechanically. The vermicelli was sent into the drying chamber and dried. The highest temperature was 50-60 ℃ and the drying time was 20-40 minutes, so that the water content was reduced to less than 13%.

The production of this product requires grinder, boiler, pulverizer, cooling room, steamer, drying chamber, shredder and so on, with an investment of at least 200000 yuan.

It must be noted that bleaching agents and preservatives must not be added at will when producing rice noodles. The production of dry rice noodles does not need to add preservatives; if wet rice noodles are produced, antiseptic treatment is needed, and calcium propionate, which accounts for 0.25% of the weight of rice noodles, can be added. The addition of any other substances that are not food must comply with the provisions of the national standard GB2760-1996.