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Factors affecting the yield of sweet potato starch for sweet potato starch processing

Date:May 30, 2019/ Industry news/ Chat online

In the sweet potato starch processing line, the yield of sweet potato starch has a great relationship with the economic benefits of starch factory. There are many factors affecting the yield of starch, including raw starch content, processing technology, crushing size, screening degree, acid slurry quality, temperature, water quality, equipment and operating procedures. It is necessary to thoroughly understand the influencing factors and actively take preventive measures.

sweet potato starch processingSweet potato starch

1. Raw materials

a. Variety---Different varieties of potatoes, the starch content is different, the starch content of the high-starch-specific varieties is generally 22%-26%, while the starch content of the edible-starch variety is 18%-22%. The edible and feed-type varieties have a starch content of only 10%-20%. Therefore, when choosing sweet potato for sweet potato starch processing, we should pay attention to the selection of sweet potato varieties with high starch content. If conditions permit, we can establish our own sweet potato plantation.

b. Stacking period---The starch rate of potato chips is the highest at the time of harvesting. The longer the stacking time, the greater the proportion of starch converted into sugar, and the lower the flour extraction rate. In addition, the decay of sweet potatoes during storage can also cause losses. Therefore, when the sweet potato is stored before sweet potato starch processing, the warehouse should be guaranteed to have a suitable temperature, thus the decay rate during storage can be minimized.

c. Quality of raw materials---In the fresh sweet potato raw materials, there will be mixed with sweet potatoes, water damage, frozen sweet potatoes, or sweet potatoes with too much impurities, which will reduce the powder yield. Therefore, in sweet potato starch processing line, we must strictly control the quality.

sweeet potato starch processingDifferent varieties of sweet potato and

2. Crushing granularity

Since sweet potato starch is present in the sweet potato tuber cells, the sweet potato needs to be ground to moisture starch granules. If the grinding is too coarse, the starch in the unbroken cells is difficult to separate, affecting the starch yield of sweet potato starch processing; if the grinding is too fine, the instantaneous temperature of the raw material is likely to rise, and some of the starch is easily gelatinized, which affects the separation.

Crushing and sieving are important factors affecting the extraction rate of sweet potato starch. Therefore, it is very important to select professional and efficient sweet potato crusher and sieving machine for sweet potato starch processing, which can help to improve the starch extraction rate and starch recovery rate.

sweet potato starch processingSweet potato crusher

3. The degree of clogging of centrifugal sieve screen

The degree of clogging of the centrifugal sieve screen has a great influence on the extraction rate of starch, and it is easily overlooked. In sweet potato starch processing line, protein and pectin in starch slurry absorb water and easily form a gel to block the mesh. In severe cases, more than 60% of the mesh holes are blocked, which affects the separation of starch. When the clogging is light, the amount of starch extracted is reduced by 5% to -15%, and when the clogging is severe, the amount of extraction is decreased by more than 40%. Therefore, the screen should be cleaned or replaced regularly.

Due to the biological characteristics of the blockage, it can not be removed with only clear water. The protein of sweet potato is mainly globulin, insoluble in water, and soluble in 2% neutral salt solution, so the screen should be cleaned with 2% neutral salt solution.

sweet potato starch processingCentrifugal sieve

4. Water quality

Good water quality not only helps to increase the yield of starch in sweet potato starch processing line, but also helps to ensure the quality of starch; on the contrary, the yield of starch is low, and the quality is difficult to guarantee.

Water and water quality issues should be considered when selecting a processing plant site. Starch and its products should be treated with soft water as much as possible. Generally required to be clear, colorless, odorless, tasteless, standing without sedimentation, no pathogens, no hydrogen sulfide and other substances harmful to humans, hardness of 15 degrees, containing calcium oxide 10 mg) or less, and the pH is preferably 6.5-8.5.

When the water quality is not good, the water should be filtered, disinfected, deodorized or softened before use. In principle, the processing water for sweet potato starch processing should meet the water quality standards for domestic water.

sweet potato starch processingWater quality

The above is the main factor affecting the extraction rate of sweet potato starch. As a professional starch equipment manufacturer, Doing Company has decades of experience, taking into account the factors that cause loss of starch yield in sweet potato starch processing line. DOING sweet potato starch equipment has high efficiency, high starch extraction rate and good product quality. If you have any questions about the factors affecting the sweet potato starch extraction rate, we have a professional engineer to answer your questions.


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