Understanding polysulfide evolution in wine: insights from accelerated ageing and real-time cellaring in different...

Area of Science:

• Food Chemistry
• Oenology
• Analytical Chemistry

Background:

• Volatile sulfur compounds (VSCs) and biothiols are critical for wine quality.
• Sulfhydryl compounds can form polysulfides, potentially leading to sulfur off-odours during aging.

Purpose of the Study:

• To investigate the evolution of sulfur species in wine during aging.
• To assess the impact of different packaging (glass bottles with various closures, aluminum cans) on sulfur compounds.
• To evaluate the effect of pre-bottling treatments (nitrogen, copper) on sulfur chemistry.

Main Methods:

• Real-time and accelerated aging studies of Chardonnay and Shiraz wines.
• Analysis of sulfur species including VSCs, biothiols, and polysulfides.
• Comparison of wine aging in glass bottles with different closures versus aluminum cans.

Main Results:

• Glutathione (GSH) accumulation was observed alongside disulfide formation (GS-SG, GS-S-SG, GS-S2-SG, Cys-S2-SG).
• Aluminum cans retained higher levels of VSCs, sulfur dioxide, and GSH.
• Wine closures with varying oxygen transmission rates significantly affected GS-SG accumulation.
• Nitrogen gas and copper treatments showed protective effects during accelerated aging.

Conclusions:

• Wine packaging plays a significant role in polysulfide chemistry and sulfur off-odour development.
• Packaging choices and pre-bottling strategies influence the management of VSCs and overall wine stability.