Enoforum 2021
IVES 9 IVES Conference Series 9 Enoforum Web 9 Enoforum Web Conference 2021 9 Oxidation vs reduction: the fate of tannins, pigments, vscs, color,SO2 and metabolomic fingerprint

Oxidation vs reduction: the fate of tannins, pigments, vscs, color,SO2 and metabolomic fingerprint

Abstract

The management of oxygen during winemaking and aging is a big issue in order to achieve high quality wines. The correct amount of O2 improves aroma, astringency, bitterness and color, however an excess of oxygen promotes the appearance of yellow and brown colors and oxidative off-odors, while its absence leads to the formation of reductive aromas. Even thought our knowledge about the reactions occurring during wine oxidation are very rich and detailed, the scientific data about the wine behaviour under reductive storage is limited. The main objective of this work was to study the metabolomic changes of eight red wines caused by the storage under different oxidative and reductive conditions.

Eight red wines were stored under eight different conditions, which include a) micro-oxygenators at 25 ºC for 3 months; b) anoxic atmosphere at 25 °C for 1, 2 and 3 months; c) anoxic atmosphere at 35 °C for 3 months; and d) control.  The following physicochemical analysis were made: LC-MS based metabolomic fingerprint, CIELab color, analyses of volatile sulfur compounds, redox potential, and basic oenological analysis. 

Changes of concentration of H2S and methanethiol (higher amount of free forms under reductive conditions) and redox potential results showed the reliability of the sample set. Color of samples evolved in a different way depending on the storage conditions, getting darker the reduced samples. Metabolomic study revealed reactions with SO2 and direct linked tannin-anthocyanin (T-A) adducts were favoured under anoxia but in the presence of oxygen, reactions with acetaldehyde and ethyl-linked T-A and tannin-tannin (adducts) were the favoured. The reaction mechanism of these reactions favoured in absence of oxygen could explain the observed changes during reductive storage.

DOI:

Publication date: April 23, 2021

Issue: Enoforum 2021

Type: Article

Authors

Ignacio Ontañón1, Diego Sánchez1, Vania Sáez2, Fulvio Mattivi2,3, Vicente Ferreira1, Panagiotis Arapitsas2

1 Laboratorio de Análisis del Aroma y Enología. Departamento de Química Analítica. Facultad de Ciencias. Instituto Agroalimentario de Aragón –IA2- (Universidad de Zaragoza-CITA). C/ Pedro Cerbuna, 12. 50009. Zaragoza, Spain.
2 Research and Innovation Centre, Food Quality and Nutrition Department, Fondazione Edmund Mach, via E. Mach 1, 38010 San Michele all’Adige, Italy
3 Center Agriculture Food Environment, University of Trento, San Michele all’Adige, Italy

Contact the author

Tags

Enoforum 2021 | IVES Conference Series

Citation

Related articles…

The Gibberellic-Acid Insensitive gene Vvgai1 impacts both vegetative growth and organogenesis rate in Vitis labruscana

Context and purpose of the study. As other perennial crops grapevine is facing the challenges of climate changes. One of the major issues is global warming and variations of the water budget.
Read More

Egg allergens in wine. Validation of a new automated method for ovalbumin quantification

Ovalbumin (ova), a natural clarifying protein, is particularly suitable for clarifying red wines. It helps improve the tannic and polyphenolic stability of the wine by removing the most astringent tannins and contributing to soften and refine the structure. Ova binds to suspended particles, proteins, polysaccharides, and, to a lesser extent, tannins through electrostatic and hydrophobic interactions, forming large complexes that can be removed from the wine through fining and/or filtration before bottling.

Read More

Influence of the number of CPPU applications on growth, mineral composition and Bunch Stem Necrosis incidence in table grape clusters

The forchlorfenuron (CPPU) application is recommended in table-grape after fruit-set to boost berry sizing, albeit growers also apply CPPU during pre-flowering with controversial advantages. We examined the effect of single (BBCH 15) and double (BBCH 15 and 57) CPPU applications (2.25 mg/L a.s.) in a commercial vineyard. At each time, 75-100 bunches belonging to 6-9 vines were sprayed, and compared with unsprayed (CTRL). Leaf stomatal conductance (gs), cluster stem diameter and length were measured. At harvest, 25 berries/repetition were sampled for chemical composition, BSN incidence was counted (N° necrotic laterals/10 cm of stem) in 40 bunches/repetition. To test the role of air VPD on mineral composition, at BBCH 77, 50 CTRL clusters were bagged to induce a low VPD.

Read More

Quantification of polysaccharides of variety Pomaces of the D.O.Ca Rioja

Pomace is one of the main residues generated by the wine industry and represents an environmental problem. Currently, there is a growing interest in the revaluation of these products because different bioactive compounds can be obtained from them, such as polyphenols, grape seed oils and polysaccharides. Red grape pomace can be an important source of polysaccharides, but they are currently little studied and even less with viable and environmental extraction processes (green extraction), such as flash extraction. The residual amount of the fraction rich in pectin (residual pulp) and component rich in hemicellulose in the pomace and the strength of association of the pectin with the cellulose-xyloglucan network depend on the degree of extractability of the polysaccharides in red winemaking and on the winemaking conditions.

Read More

Effect of terroir on the quality evolution of Cabernet-Sauvignon in Penedès A.0.C.

Le Cabernet-Sauvignon est un cépage très répandu dans la région du Penedès (Espagne) où cette variété peut bien s’adapter et donne des produits de haute qualité.

Read More