Identification and Sensory Evaluation of 3‑Sulfanylhexyl Propionate and 3‑Sulfanylhexyl Butyrate in Wine

TL;DR

New sulfur-containing compounds in wine were identified and found to contribute to tropical fruit aromas, though they are present in low concentrations.

Contribution

The first identification of 3-sulfanylhexyl propionate and 3-sulfanylhexyl butyrate in wines and their sensory characterization.

Findings

3-sulfanylhexyl propionate and 3-sulfanylhexyl butyrate were detected in commercial wines.

The compounds contribute to grapefruit, passionfruit, and tropical fruit aromas in wine.

Concentrations in most wines were below sensory detection thresholds but may act synergistically.

Abstract

Two new polyfunctional thiols, 3-sulfanylhexyl propionate
(3SHP)
and 3-sulfanylhexyl butyrate (3SHB), were detected in wines, synthesized
as reference standards, and their sensory properties were characterized.
Fermentations supplemented with short-chain fatty acids (propionic
acid and butyric acid) generated 3SHP and 3SHB, which were confirmed
by GC-MS using synthetic standards. Analysis of commercial wines from
Scheurebe, Sauvignon blanc, and Verdejo further verified the presence
of 3SHP and 3SHB, reporting their first identification in wines to
our knowledge. To determine the influence of these esters on wine
aroma, their odor threshold values (detection and recognition thresholds)
were identified. Here, both compounds were described with grapefruit,
passionfruit and tropical fruit descriptors. Although concentrations
in many commercial samples were below sensory detection thresholds,
synergistic sensory interactions with other polyfunctional thiols
to the tropical wine aroma can be assumed.

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