Soaking process for corn starch

When the corn in the steel bin needs to be processed, open the valve and send it to the cleaning tank of the workshop by the scraper and the elevator Hydraulic transport to the soaking tank, with sulfite for soaking.

Soaking is the key process of corn starch production, soaking quality directly affects the flour yield and starch quality. The purpose of soaking is to change the structure and physical and chemical properties of endosperm, weaken the starch bond, reduce the strength of corn grains, leach soluble substances, and inhibit microbial spawn.

The soaking is carried out in an aqueous solution of sulfite. A semi-continuous process is generally used. Soaking irrigation 8, during the soaking process, the corn remains static in the tank, and the soaking liquid is transported in the tank from one side to the other, and the new sulfite solution is always kept in contact with the corn that has been soaked for the longest time (about to end the soaking), and the newly entered corn is in contact with the soaking liquid that is about to be discharged, so as to maintain the best soaking effect.

The soaking temperature is (50±2) ℃, the concentration of soaking sulfite is 0.2 ~ 0.25%, and the soaking time is 48 ~ 60h. After soaking, the dry matter of the dilute corn pulp is 5% ~ 9%, the pH value is 3.9 ~ 4.1, and it is sent to the evaporation process to concentrate into the corn pulp containing more than 40% dry matter. At the end of the corn water 40% ~ 46%, soluble matter is not more than 2.5%, can be squeezed by hand, the germ is completely extruded.