How Soybean Oil Is Made?

Soybean oil is made by extracting oil from soybeans, typically through a process involving cleaning, cracking, and then either mechanical pressing or solvent extraction. Solvent extraction, commonly using hexane, is the most common method. The extracted oil is then refined to improve its quality and remove impurities.

Soybean oil is an edible oil with a light and clean flavor that is commonly used for cooking. The oil is 60% polyunsaturated fat and 24% monounsaturated fat, according to the National Soybean Research Laboratory, making it a heart-healthy oil.

Soybean oil is extracted by several methods. Commercially, chemical extraction using hexane is common, with this method, the oil yield is typically aroud 19% (the dreg oil in meal is about 1%). Another method is mechanical pressing, with this method, however, the oil yield is always around 13% (the dreg oil in cake is about 7%). cold pressing the beans using a small hand operated seed oil press is the most available method for extracting the virgin soybean oil at home.

The extraction of soybean oil using hexane.

Soybean oil can also be extracted using hexane, an organic solvent often used for extractions. To do this, after cleaning, the seeds are introduced into an extractor where they are mixed with hexane. The oil then dissolves in the hexane. The mixture is then heated to evaporate the hexane and retain only the soybean oil. This step is carried out in a evaporator, a piece of equipment where the temperature and pressure are controlled in order to best preserve the soybean oil. The oil is then refined to remove impurities.

• Benefits : Hexane extraction allows for a significant yield, approximately 97%.
• Drawbacks : Hexane is a costly, polluting solvent and poses a significant public health concern.

The extraction of soybean oil through cold pressing.

Soy is a legume native to China and has been traditionally cultivated in Asia for several centuries. Its seeds are intended for several uses, including the production of vegetable oil. This oil is in turn produced for various applications in culinary, therapeutic, and cosmetic worlds. There are several methods to extract soy oil from the seeds, the first being cold pressing.

About 3 months after sowing, when they have reached maturity, the soybeans are harvested then cleaned, in order to remove any impurities that may be attached to their surface. They are then dried using a dryer, following the convection process, so that their residual moisture reaches about 10%. Once the beans are sufficiently dry, they are mechanically pressed flat to extract the oil. They are then introduced into a screw press, kept at a temperature below 60°C, hence the term “cold pressing”. Finally, the obtained oil is then decanted, filtered or centrifuged to concentrate it.

• Benefits : This method is 100% natural and does not require any chemical solvents. Moreover, the process takes place at low temperature, so the oil is not degraded and retains all its active ingredients. Finally, this technique is respectful of the environment, as it requires little energy and prevents the release of polluting residues.
• Drawbacks : The yield obtained from a cold press is relatively low compared to the use of other techniques.