What Are the Methods of Edible Oil Production?

The production process of edible oil includes two main extraction methods: pressing and solvent extraction.

Two key oil extraction methods: pressing and solvent extraction

Pressing applies physical pressure to separate oil from raw materials, originating from traditional oil-making techniques but now industrialized. Since no chemical additives are involved, pressed oil retains its natural components, but the downside is a lower yield.

Solvent extraction, in contrast, uses approved solvents to dissolve and extract oil from processed raw materials, followed by strict procedures to remove residual solvents. Compared to pressing, solvent extraction leaves less oil residue in oil cakes, achieves higher yields, reduces costs, and fully utilizes oilseed resources.

Suitability of Different Methods

Edible oils vary in chemical composition and physical properties, making pressing and solvent extraction suitable for different raw materials:

High oil content seeds, such as rapeseed, usually undergo pre-pressing followed by solvent extraction.

Low oil content seeds, such as soybeans, are directly extracted using solvents.

Certain seeds, like sesame and peanuts, which produce oils with unique flavors, are processed through pressing to preserve their original taste.

Impact on Oil Flavor and Refining

Pressed oils typically undergo minimal processing, preserving the natural aroma of the raw materials, which may appeal more to Chinese taste preferences. Solvent-extracted oils undergo refining processes such as degumming, deacidification, decolorization, and deodorization, effectively removing unwanted flavors like the bean smell from soybean oil.

Crude oil, obtained solely through pressing or extraction, contains impurities like gums, free fatty acids, and pigments, making it unsuitable for direct consumption. To ensure safety, crude oil must undergo refining, including washing, alkali neutralization, deacidification, decolorization, and deodorization, transforming it into clear, refined oil that meets industry standards.Ultimately, the key factor in determining edible oil quality is not the production method but the level of refining and adherence to strict processing standards.