Investigating the factors driving concentrations of volatile thiols and their precursors in white wines: The impact of Botrytis cinerea and grape variety.

3-Sulfanylhexan-1-ol (3SH) and 3-sulfanylhexyl acetate (3SHA) are highly odiferous impact odorants in wines, imparting tropical aromas. Despite having a good understanding of how vintage, grape variety, region of production, and Botrytis cinerea infection affect the concentration of these volatile thiols, the influence of these factors on the concentrations of thiol precursors has not been comprehensively studied. Therefore, the concentrations of 3SH and 3SHA, and five precursors to 3SH, were quantitated for 40 commercial white wines, to explore how vintage, variety, region, and Botrytis cinerea infection, influence both thiol and precursor concentrations. The most impactful factors on wine thiol concentration were Botrytis and variety, although these factors influenced the thiols differently. 3SHA concentrations were also modulated, although less strongly, by vintage and region. However, only Botrytis and variety influenced precursor types and concentrations. Ultimately, variety was the most impactful factor in thiol and thiol precursor concentrations in the wines studied herein.