Soy sauce impurity removal

In the traditional soy sauce production process, the original soy sauce is sterilized, enzyme eliminated, aroma blended, color increased, and suspended solids removed by heating. This method consumes a lot of energy and the sterilizer is prone to scaling. If not operated properly, soy sauce may also have a burnt taste and a dark color.

After the 1990s, inorganic ceramic membrane separation technology began to be widely applied in the fields of food and fermentation. Especially in the processing of soy sauce, edible oil, draft beer, wine, fruit wine, fruit juice, dairy products, etc., many enterprises have achieved good economic and social benefits, making significant contributions to the application of ceramic membrane separation technology in domestic enterprises to improve product quality, reduce production costs, and increase economic benefits.

Principle of Ceramic Membrane Filtration

Ceramic membrane filtration uses cross flow filtration method. The basic principle of cross flow filtration is that the feed liquid circulates parallel to the membrane surface at high speed under the drive of the pump. Under the action of pressure, small molecules and particles smaller than the membrane pore size pass through the membrane to form a filtrate for filtration. Substances larger than the pore size of the membrane are intercepted by the membrane, and turbulent flow is formed due to the high-speed movement of the filtrate. The membrane surface is continuously washed away, carrying away a small amount of solid substances that are intercepted by the membrane and attached to the membrane, thereby keeping the fouling layer at a relatively thin level, preventing membrane blockage, and maintaining normal filtration. The filtrate continuously circulates, and the solid concentration increases. When the concentration reaches a certain level, it is automatically or manually discharged, thus achieving the purpose of solid-liquid separation.

Process description of soy sauce inorganic film impurity removal treatment

Soy sauce crude oil (liquid) is homogenized and evenly distributed in the crude oil storage tank, and lifted into the bag filter by the lifting pump. The soy sauce crude oil to be filtered flows into the bag filter under pressure from the top of the filter bag, and is evenly distributed on the filtering surface of the entire filter bag. Soy sauce flows out from the inside of the filter bag, and the filtered particles and impurities (with a diameter of 25 μ m) are left in the bag through surface filtration, deep filtration, and adsorption filtration of the filter bag. The filter residue is regularly manually cleaned and transported to the waste tank for external processing.

The soy sauce crude oil (liquid) pretreated by the bag filter flows automatically to the circulation box of the ceramic membrane ultrafiltration treatment device, and then enters the membrane separation device for filtration by the raw material pump. The processed soy sauce is directly transported to the next production process through the pipeline system. The concentrated solution is pumped into the concentrated solution storage tank by the raw material pump of the membrane separation system and regularly transported for processing; The residual liquid in the system is discharged to the residual liquid storage tank and regularly discharged to the soy sauce crude oil storage tank for processing along with the next batch of materials. After processing a batch of liquid, clean and regenerate the inorganic ceramic membrane. So repeatedly, the process of removing impurities from soy sauce is completed.