The resulting pressed oil is called by different names mainly, crude oil, raw oil, or unrefined oil. Crude oil pressed using the heat method must be subjected to several treatments before it can be used. The crystals are removed by filtration after the oil has been cooled. Therefore the higher the degree of hydrogenation, the more solids the fat. That is the reason why cold-pressed oils must be stored with greater care than refined oils.
Unrefined oils are darker and have a more pronounced flavor than refined oils.
However, this stronger flavor is not to be confused with rancidity. The equipment used for the above processes are extremely complicated to kosher sterilize if it was used for a non-kosher production.