Solvent extraction of edible oil is an important technology to extract oil efficiently, which is mainly divided into two ways: direct extraction and pre-press extraction.

Direct extraction is suitable for oil with low oil content such as soybeans and rice bran. After cleaning, crushing, embryo rolling and other pretreatment, the oil directly enters the extractor to contact with the solvent, and the oil dissolves to form mixed oil, and then the crude oil is separated by evaporation and stripping. The process flow is simple, the equipment investment is low, and the oil in low oil content oil can be fully extracted to improve the oil yield.

Pre-press extraction is often used for oilseeds with high oil content, such as rapeseeds and peanuts. First, most of the oil is extracted by pre-pressing, and then the remaining pressed cakes are extracted by solvent. Pre-pressing makes the cake structure loose, which is beneficial to leaching, and the oil obtained by pre-pressing has better quality and the subsequent refining is easier.

The two processes have their own advantages, and enterprises can choose flexibly according to the characteristics of oil and production demand to meet the diversified supply of edible oil in the market.