Expeller Pressed Process
The first step of the expeller-pressed process is to pass the canola over a screen type cleaner. This removes the majority of the foreign material that is present with the canola seed when it is received from the farm.
The cleaned canola seed is then indirectly heated to a temperature where it becomes more pliable, and simultaneously its moisture is adjusted to a level that is optimum to feed the pre-presses, which are the first set of expellers.
The solids leaving the first expellers are now referred to as “pre-press cake,” and that cake is again indirectly heated and reduced in moisture to a level that is optimum to feed the full presses, which are the second set of expellers. The solid material leaving the second set of expellers is now considered canola meal and is cooled and ground to the desired consistency of our customers.
Unlike traditional canola processing plants, which saturate the canola cake with solvent to remove a portion of the canola oil in the seed, Pacific Coast Canola’s expeller-pressed canola oil and meal never come into contact with any solvent.
The oil that is removed from both the first and second set of expellers is collected and passed through two sets of solids separation processes to remove the vast majority of any fine particles that were expelled with the oil. The oil is then considered crude canola oil ready to be refined for human consumption.
How Is the Expeller-Pressed Process Different?
In a conventional canola processing plant, about 65 percent of the oil is removed via a single set of expellers, but most of the remaining 35 percent is removed from the canola solids using a solvent – typically hexane. Although almost all of the hexane is distilled away from the crude oil, some of it does remain. Some of the solvent-based extraction plants do segregate the expeller crude oil from the extraction-derived crude oil, but most mix them together. This means all of the crude oil will come into contact with the hexane that came from the extraction oil.
Expeller-pressed canola oil does not use any solvent or chemical extraction of the canola oil from the seed or meal.