As with many things in winemaking, however, glutathione does not necessarily have only positive effects. Its qualities can also create other problems, depending on how the wine is managed and also on the complex chemistry of a particular wine. For instance, explains Maurizio Ugliano, “there are other components in the thiol family that produce reductive aromas, and glutathione protects those as well.” In other words, fruity aromas might still fade and be overtaken by less pleasant, reductive aromas – things like burnt rubber, garlic and other smells you would generally rather not have in your wine