The Effect of Elemental Sulfur, Yeast Strain, and Fermentation Medium on Hydrogen Sulfide Production During Fermentation

Abstract

The effect of elemental sulfur on hydrogen sulfide production was investigated in stirred fermentations of a reconstituted commercial white grape juice or a defined juice-like medium. Nine commercial wine yeast strains and three levels of elemental sulfur were studied (0, 1.7, and 3.4 mg/L fermentation) in 117 trials. These levels represent the observed elemental sulfur residues at harvest in commercial vineyards for the 1989 and 1990 seasons (12). The cumulative hydrogen sulfide produced was measured using cadmium hydroxide traps that were collected at 24-hour intervals for five days. Two peaks of hydrogen sulfide production occurred during the fermentations. Peak 1 occurred earlier and was more intense than Peak 2. The two peaks occurred independently of each other. Peak 1 was associated with the yeast strain that was used. Peak 2 was associated with the medium that was used. The amount of elemental sulfur added to the medium was not related to the amount of hydrogen sulfide produced in these fermentations. Specific yeast-medium-sulfur interactions were apparent.