Volatile organic compounds (VOC’s) is a catch-all term for a group of chemicals characterized by a low boiling point. Because they easily evaporate, they are often found in a gaseous state, and in some cases present a danger to human and animal health, given that they can be easily breathed in. In the feed industry, silage is a major producer of VOC’s, and chief among the scala of chemicals produced, is ethanol, which can influence feed intakes. To inhibit the production of ethanol, heterolactic lactic acid bacteria are added to the silage; they produce acetic acid, which influences the ethnaol-producing yeasts in the silage.