Evidence of the Relationship between the Oxygen Radical Absorbance Capacity (ORAC) and the Potential Exposure of White Wines to Atypical Aging (ATA).

Atypical aging (ATA) is a well-known wine defect that leads to unacceptable off-odors of wet mop, soap, waxy, furniture varnish, and dish rag. The main compound that is responsible for these undesired scents, 2-aminoacetophenone (AAP), results from the oxidative degradation of 3-indole acetic acid. This study aimed to investigate different technological factors for a possible effect on the oxygen radical absorption capacity (ORAC) and ATA development in white wine.

Monitoring hydrogen sulfide de-novo formation from polysulfides present in wine using ion chromatography and ultra high-pressure liquid chromatography combined with fraction collection and high-resolution mass spectrometry.

The study of polysulfides has been a recent topic of interest for wine research due to the possibility of these compounds to release hydrogen sulfide (HS) during storage. However, studying these compounds has been challenging for several reasons. Polysulfides are low in concentration in natural samples, they are chemically unstable and pure standards of the single compounds (RSR with n > 2) are not commercially available.

Time course accumulation of polysulfides in Chardonnay and model juice fermentations.

Over the last five years, polysulfides in wine have become a topic of interest. The finding that both yeast and the wine composition could contribute to the formation and evolution of these compounds has prompted several studies, further corroborated by the discovery of a link between polysulfides and HS release during ageing. In the present study, the accumulation of cysteinylated and glutathionylated polysulfides was followed during fermentation for the first time.

Identification and characterisation of thiolated polysulfides in must and wine using online SPE UHPLC-HRMS.

3-Mercaptohexanol and 4-methyl-4-mercaptopentanone are volatile thiols with a low perception threshold and are found in relatively low concentrations in several types of wines, e.g. Sauvignon blanc.