Straightforward synthesis of labeled S-3-(hexan-1-ol)-glutathione and S-4-(4-methylpentan-2-one)- glutathione has been developed through a conjugate addition optimization study. Sauvignon blanc fermentation experiments with the [2H10] S-4-(4-methylpentan-2-one)-glutathione used as a tracer released the corresponding deuterated thiol, thus proving the direct relationship with the 4-mercapto-4- methylpentan-2-one under enological conditions. The conversion yield of such transformation was estimated to be close to 0.3%, opening an avenue for additional study on varietal thiol biogenesis.