Soybean oil is one of the common edible oils in daily life, and its production process mainly includes soybean pretreatment, pressing and solvent extraction. In soybean oil processing plant, the common soybean oil extraction methods mainly include the following:

1. Pressing extraction method

Pressing is a traditional way to extract soybean oil. The method applies high pressure to the treated soybean through mechanical equipment to separate the oil from the soybean. The advantages of pressing method are simple operation, environmentally friendly production process and no need to use chemical solvents. But its disadvantage is that the oil yield is relatively low, which is suitable for small processing plants or products with high requirements for natural food.

2. Solvent extraction method

Solvent extraction method is the most commonly used extraction method of soybean oil in industrial production at present. This method uses organic solvent (such as n-hexane) to dissolve soybean and extract oil from soybean. The biggest advantage of this method is high oil yield and full utilization of raw materials. However, due to the use of chemical solvents, it is necessary to strictly control solvent residues in the production process to ensure food safety.

3. Combination of pressing and solvent extraction 

This method combines the advantages of pressing method and solvent extraction method. First, soybean is pressed initially, and then the pressed cake is leached. This method not only improves the oil yield, but also reduces the amount of solvent used, which is a popular process at present.

4. Cold pressing method

Cold pressing method is to press at low temperature, so as to keep the nutrients and natural flavor of soybean as much as possible. This method is suitable for producing high-end edible oil, but because of the poor fluidity of oil at low temperature, the oil yield is low and the cost is relatively high.

Different soybean oil extraction methods have their own advantages and disadvantages, and manufacturers will choose the appropriate technology according to market demand and product positioning. With the continuous progress of technology, the processing technology of soybean oil is constantly optimized to meet consumers’ demand for healthy, safe and high-quality edible oil.