Expert response from Robert Wager M.Sc.
Faculty Member, Biology Department, Vancouver Island University in Nanaimo BC Canada
Thursday, 19/05/2016 19:02
Although this seems like a very straight forward question, there are different answers depending on which jurisdiction one ifis talking about and what one’s definition of GMO is. For the purpose of this answer we will define GMO as any organism that has had its DNA altered using genetic engineering (GE).
In the case of ethanol production there are several sources of components that are or have been derived from genetically engineered (scientifically correct term for GM) organisms. The carbon source may be from GE sugar beets or GE corn and the yeasts used to ferment the carbon source to produce ethanol may be genetically engineered. The sugar from GE beets or the fructose from GE corn are identical to sugars derived from non-GE sources so the “GMO” component has been removed by the sugar purification process. There are no GMO varieties of wheat, barley or grapes commercialized at this time. The European Union GMO Compass site has a detailed explanation of the different GE yeasts and where they are used. Fermentation converts the carbon source to ethanol and CO2. The ethanol is then separated from everything else by distillation.
In the strictest sense distillation always removes all organisms so there are no GMO’s in ethanol distillate. Ethanol from distillation is 95.5 percent pure. The remaining 4.5 percent is H2O. This water forms an azeotrope complex with the ethanol. There is no detectable DNA or proteins found in ethanol and therefore it is GMO free by most definitions. See related question I’ve answered here, Finish product ethanol after distillation which has no traces of GMO, made from GMO corn crop is it consider to be GMO free or not? for more details.
Video: GMO Answers at SXSW