Canola Oil Expeller Pressed
Canola oil [kan-OH-luh] "The market name for rapeseed oil which, as might be assumed from the name, is expressed from rape seeds. For obvious reasons, the name was changed to canola by the Canadian seed-oil industry. Canola is, in fact, Canada's most widely used oil. It's commonly referred to there as lear oil, for "low erucic acid rapeseed" oil. The popularity of canola oil is rising fast in the United States, probably because it's been discovered to be lower in saturated fat (about 6 percent) than any other oil. This compares to the saturated fat content of peanut oil (about 18 percent) and palm oil (at an incredibly high 79 percent). Another canola oil selling point is that it contains more cholesterol-balancing monounsaturated fat than any oil except olive oil. It also has the distinction of containing Omega-3 fatty acids, the wonder polyunsaturated fat reputed to not only lower both cholesterol and triglycerides, but to contribute to brain growth and development as well. The bland-tasting canola oil is suitable both for cooking and for salad dressings." -- from The Food Lover's Companion, by Sharon Tyler Herbst. Cold Extraction Methods Cold Pressed Cold pressing refers to oils obtained through pressing and grinding fruit or seeds with the use of heavy granite millstones or modern stainless steel presses, which are found in large commercial operations. Although pressing and grinding produces heat through friction, the temperature must not rise above 120ÂºF for any oil to be considered cold pressed. The maximum temperature for cold pressed olive oil is somewhat lower. Olive, sesame, peanut, and sunflower are among the oils obtained from cold pressing. (Highly refined versions of these oils are also produced.) Cold pressed oils retain all of their flavor, aroma, and nutritional value. Vacuum Extraction Vacuum extraction is another method of cold extraction that produces oils with an expeller process. The process occurs in an atmosphere with no oxygen or light. The temperature during the expeller process may be as low as 70ÂºF. Heat Extraction Methods Expeller Pressed Expeller pressing is like cold pressing except that extreme pressure is added during the pressing. As much pressure as 15 tons per square inch is used to squeeze the oil from the fruit or seeds. The high pressure also produces high heat (as high as 300ÂºF ) through friction, so the oils produced with the expeller process cannot be considered cold pressed. The oils obtained with this method retain much their flavor, aroma, and nutritional value, but not to the extent of cold pressed oils. Solvent Extraction Chemical solvents are used to extract oil, which is then boiled to eliminate most of the solvents. Further refining such as bleaching, deodorizing, and heating to high temperatures cleanses the oil, resulting in a product that has very little of the original flavor, aroma, or nutrients contained in the seeds or fruit before processing. Most of the oils produced with this method have a high smoke point and a long shelf life.