Ever heard of "Gutter Oil"?
Apparently around 10% of cooking oil used in China is derived from gutter oil.
http://en.wikipedia.org/wiki/Gutter_oil
If you watch this video you will never eat food in china again:
http://www.businessinsider.com.au/chinese-street-vendors-use-gutter-oil-2013-10
Apparently around 10% of cooking oil used in China is derived from gutter oil.
http://en.wikipedia.org/wiki/Gutter_oil
If you watch this video you will never eat food in china again:
http://www.businessinsider.com.au/chinese-street-vendors-use-gutter-oil-2013-10