How does the way an oil or fat is processed impact its nutritional value? What makes cold-pressed oils superior?
From olive oil to sesame oil, the way that oil is extracted has a direct effect on how the oil tastes and the amount of nutrients it has to offer. Using heat to extract the oil allows more oil to be produced, but heat can degrade the oil's flavor and nutritional quality.
Using low-heat methods produces a higher quality oil, albeit in lesser quantities.
Extracting oil with cold-pressing involves crushing the seed or nut and forcing out the oil manually.
The seeds are then dropped inside a cylinder that contains a rotating screw. This screw grinds and crushes the seeds until the oil is extracted. Small holes in the bottom of the cylinder allow the oil to escape into a collection container. Although some heat is generated through friction as the screw breaks down the seeds, it's usually not enough heat to damage the oil.
John Tjenos, LMT, NTP