High Quality Content by WIKIPEDIA articles! Gutter oil (simplified Chinese: ???; traditional Chinese: ???; pinyin: Digou you) is a term used in China to describe illicit cooking oil which has been recycled from waste oil collected from sources such as restaurant fryers, drains, grease traps and slaughterhouse waste. Reprocessing is often very rudimentary; techniques include filtration, boiling, refining and the removal of adulterants. It is then packaged and resold as a cheaper alternative to normal cooking oil. Another version of gutter oil uses discarded animal parts, animal fat and skins, internal organs, and expired or otherwise low-quality meat which is then cooked in large vats in order to extract the oil. Used kitchen oil can be purchased for between 859 and 937 dollars per ton while the cleaned and refined product can sell for 1,560 per ton. Thus there is great economic incentive to produce and sell gutter oil. It is estimated that up to one in every ten lower market...