terclim by ICS banner
IVES 9 IVES Conference Series 9 PHOTO OXIDATION OF LUGANA WINES: INFLUENCE OF YEASTS AND RESIDUAL NITROGEN ON VSCS PROFILE

PHOTO OXIDATION OF LUGANA WINES: INFLUENCE OF YEASTS AND RESIDUAL NITROGEN ON VSCS PROFILE

Abstract

Lugana wines are made from Turbiana grapes. In recent times, many white and rosé wines are bottled and stored in flint glass bottles because of commercial appeal. However, this practice could worsen the aroma profile of the wine, especially as regards the development of volatile sulfur compounds (VSCs). This study aims to investigate the consequences of exposure to light in flint bottles on VSCs profile of Lugana wines fermented with two different yeasts and with different post-fermentation residual nitrogen.

Wines were produced with a standard protocol with Turbiana grapes with two different yeasts. During the alcoholic fermentation of the must additions of inorganic or organic nitrogen supply were made. Wines were bottled in inert conditions in flint bottles and exposed for 30 days to light at controlled temperature of 20°C. Subsequently the VSCs profile of the wines was analyzed using GC-MS techniques. Wines were then subjected to the sorting task sensory analysis.

The VSCs profile analyzed showed significant differences for carbon disulfide, methanethiol, dimethyl sulfide and dimethyl trisulfide. The variability given by the yeasts leads to statistically significant differences only for diethyl sulfide and dimethyl disulfide. Regarding the differences given by the residual nitrogen, the samples in the transparent bottles with higher residual nitrogen showed a greater increase of sulfur compounds. Wines with a higher organic residual nitrogen showed significant differences for carbon disulfide, methanethiol, dimethyl sulfide, diethyl sulfide and dimethyl disulfide. Linear correla-tions were found between residual nitrogen in wines and carbon disulfide, methanethiol and dimethyl sulfide. The sensory analysis sorting task highlighted the formation of two main classifications made up of wines with a low residual nitrogen and wines with a high residual organic nitrogen. This study showed the great impact of light exposure in transparent bottles has on the aromatic and sensory quality and how the post-fermentation residual nitrogen, especially for organic nitrogen, in the wines can worsen this qualitative deterioration. This underlines the impact of the presence of residual nitrogen on the stability of the wine during maturation, placing the attention on the dose of nitrogenous nutrition introduced during alcoholic fermentation. The choice of yeast strain seems to have an influence, albeit minor, on the development of VSCs compounds in wines exposed to light.

ACKNOWLEDGMENTS: The present work was supported by Laffort, France.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Beatrice Perina1, Virginie Moine², Arnaud Massot², Davide Slaghenaufi¹, Giovanni Luzzini¹, Maurizio Ugliano¹

1. Department of Biotechnology, University of Verona
2. Biolaffort, France

Contact the author*

Keywords

Light-induced oxidation, Lugana wine, VSCs profile, Nitrogen

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

PESTICIDE RESIDUES IN THE VINEYARD ENVIRONMENTS: VINE LEAVES, GRAPE BERRIES, WINES, HONEYBEES AND ASIAN HORNETS

Synthetic pesticides are widely used in viticulture to ensure steady harvest quality and quantity. Fungicides are primarily used to control grapevine diseases but insecticides and herbicides are likewise used. Pesticide residues in viticultural areas currently represent a strong societal concern, but may also affect different trophic chains in such areas. In this project we wish to analyse honeybees collected from hives placed in different vineyards, their natural predator (the invasive hornet Vespa velutina), as well as the honey, grape berries, and wines produced.

Read More

EFFECT OF FERMENTATION TEMPERATURE GRADIENT AND SKIN CONTACT ON ESTER AND THIOL PRODUCTION AND TROPICAL FRUIT PERCEPTION IN CHARDONNAY WINES

Wines with tropical fruit aromas have become increasingly more available1,2. With increased availability of different wine styles, it has become important to understand the compounds that cause the fruity aromas in wine. Previous work using micro fermentations showed that fermentation temperature gradients and time on skins resulted in an increase in thiol and ester compounds post fermentation and these compounds are known to cause tropical fruit aroma in wines³. This work aimed to scale up these fermentations/operations to determine if the desired aromas could still be achieved and if there is a perceivable difference in tropical fruit aromas, liking, and emotional response in the wines at the consumer level.

Read More

Metabolomics for grape and wine research: exploring the contributions of amino acids to wine flavour

A critical aspect of wine quality is the overall expression of wine flavour, which is formed by the interplay of volatile aroma compounds, their precursors, and taste and matrix components.
Grapes directly contribute to wine only a small number of potent aroma compounds, and the unique
sensory attributes and perceived quality of a wine result from combining 100s of metabolites of grapes, yeast and bacteria, and oak wood.

Read More

INVESTIGATION OF FILM COATINGS AS A PROTECTIVE LAYER IN REDUCING THE ABSORPTION OF SMOKE PHENOLS INTO PINOT NOIR GRAPES

Wine grapes exposed to wildfire smoke have resulted in wines with burnt and ashy sensory characteristics¹, that are undesirable qualities in wine. In extreme wildfire events, this can lead to total loss of grape crop. Currently there are no effective solutions in the market to prevent the uptake of smoke compounds into grapes. In this study, previously developed innovative film coatings were tested to analyze their effectiveness in reducing smoke phenol absorption². Four different cellulose nanofiber-based film types were investigated.

Read More

IMPACT OF MUST NITROGEN DEFICIENCY ON WHITE WINE COMPOSITION DEPENDING ON GRAPE VARIETY

Nitrogen (N) nutrition of the vineyard strongly influences the must and the wine compositions. Several chemical markers present in wine (i.e., proline, succinic acid, higher alcohols and phenolic compounds) have been proposed for the cultivar Chasselas, as indicators of N deficiency in the grape must at harvest [1]. Grape genetics potentially influences the impact of N deficiency on grape composition, as well as on the concentration of potential indicators in the wine. The goal of this study was to evaluate if the che- mical markers found in Chasselas wine can be extended for other white wines to indicate N deficiency in the grape must.

Read More