Corn oil is extracted from corn embryo and becomes edible corn oil after further production processes such as refining. Edible corn oil has a milder taste than other edible oils and its high smoke point makes it a valuable frying oil for cooking use. According to USDA National Nutrient Database for Standard Reference, Release 21 released by the U.S. Department of Agriculture in 2008, compared to other popular edible vegetable oils such as soybean oil, rapeseed oil, peanut oil and cotton seed oil, edible corn oil generally has a higher polyunsaturated fatty acid level and/or lower saturated fatty acid level.