| − | '''Butyric Acid''' (C<sub>4</sub>H<sub>8</sub>O<sub>2</sub>) is a fatty acid commonly found in rotten butter, Parmesan cheese, and emesis. It has an unpleasant smell which can be picked up by mammals with good scent abilities at 10ppb whilst humans can smell it at 10ppm. | + | '''Butyric acid''' (CH<sub>3</sub>(CH<sub>2</sub>)<sub>2</sub>COOH) is a [[fatty acid]] commonly found in rotten [[butter]], parmesan [[cheese]], and [[vomit]]. It has an unpleasant smell which can be detected by humans in concentrations of 10 parts per million (ppm) |