- Summer 1996 "Update" Newsletter Article -
Enologists eye new data on ethyl carbamate
From CATI Publication #960701
Copyright © 1996. All rights reserved.
A pair of enology researchers at California State University, Fresno has taken another step toward solving the mystery of ethyl carbamate formation in wine.
Professor Carlos Muller and winemaster Ken Fugelsang have released research information confirming that the combination of two common wine compounds does result in the formation of ethyl carbamate, a compound at one time identified as a mild carcinogen.
Since its discovery, wineries have taken measures to successfully reduce levels of ethyl carbamate in finished wine. However, some wineries continue to experience the "puzzling problem" in which wines that have tested negative for ethyl carbamate at bottling show the compound present after "accelerated storage" tests, stated Muller in explaining the reasons for the research.
Recent tests focused on 3a,6a- dimethylglycoluril (DMGU), a compound formed by the reaction of diacetyl and urea, two other compounds commonly found in grape juice and wine. Initial tests a year ago suggested that DMGU was not a likely precursor to the formation of ethyl carbamate in finished wine, Muller said. However, in the first trials some isolation difficulties required that the study be carried out again. This time the results were more clear, indicating that DMGU definitely is a precursor to formation of ethyl carbamate, under accelerated storage conditions.
Although more study needs to be conducted on other compounds that play a role in this problem, Muller said the new information will be a valuable addition to the current knowledge base.
The details of this research are available in a publication just released by Fresno State's California Agricultural Technology Institute (CATI). It is titled "3a,6a-Dimethylglycoluril, the Product of the Interaction of Urea and Diacetyl, as a Source of Post- bottling Ethyl Carbamate in Wines." To obtain a copy, see the Publications available form on Page 7.
More information on this project may be obtained by contacting the researchers through the Viticulture and Enology Research Center, at (559) 278-2089.{ page top }