Reductive off-odors in wines: Formation and release of H2S and methanethiol during the accelerated anoxic storage of wines. (15th May 2016)

• Record Type: Journal Article
• Authors: Franco-Luesma, Ernesto; Ferreira, Vicente
• Is Part Of: Food chemistry. Volume 199(2016)
• Page Start: 42
• Page End: 50
• Publication Date: 2016-05-15
• Subjects: Reduction -- Copper -- Sulfur -- Bonded H2S -- Wine aging -- De novo formation; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2015.11.111
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Wines contain high proportions of H2 S and MeSH as bonded non-volatile forms. Total contents of H2 S and MeSH strongly linked to wine metal and S-amino acids. Bonded fraction decreases significantly with wine age and during anoxic storage. De novo formation is observed in all cases except for H2 S in reds. Release is main source of H2 S and de novo formation is dominant for MeSH. Abstract: In order to better understand the processes involved in the development of H2 S and methanethiol (MeSH) along anoxic storage of wines, 24 wines were stored in strict anoxia at 50 °C for 3 weeks. Free and total forms of H2 S and MeSH were measured at different times. Results showed that: (1) all wines contain relevant proportions of bonded forms of H2 S and MeSH (93% and 47% on average); (2) such % decreases with age; (3) levels of total forms are related to wine metal composition; (4) anoxic storage brings about an increase of free forms, a strong decrease in the percentage of bonded forms, and except for H2 S in red wines, an increase in total forms. Both de novo formation and release contribute to reductive off-odors. Release is predominant for reds and H2 S, while at 50 °C, de novo formation dominates for whites and rosés and MeSH.