Hydrogen Sulfide Generation from Sulfur Dioxide in the Presence of Aluminum in Acidic Solutions such as Wine and Cider
Brent Trela,* Chris Scarlata and Christopher
*Ball Corporation, 9343 West 108th Circle, Broomfield, CO 80021 (firstname.lastname@example.org)
Hydrogen sulfide (H2S) can be generated when sulfur dioxide (SO2) is reduced in the presence of Al (0) under acidic conditions. Fermented products, including wines, ciders, or other acidic, SO2-containing products such as model wines, can form H2S when in contact with oxidizing metallic aluminum. Other forms of Al such as oxides or salts do not generate the reductive, electron-liberating potential of corroding Al to generate H2S from sulfites. H2S production is thermodynamically strongly favored and other VSCs are not generated. In this work, model and white wines containing molecular SO2 proceeded to produce measurable and sensorially significant amounts of H2S. Red wines were also tested, but inconsistently produced H2S, likely due to higher pH and lower molecular SO2 concentration and/or other complexing factors. This work illustrates the relationship among sulfides and their precursor sulfites, pH, Al, and some potential complexing factors in red wines.
Funding Support: Ball Corporation