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…

DETERMINATION OF MINERAL COMPOSITION IN CV. TERAN (VITIS VINIFERA L.) RED WINE AFFECTED BY PRE-FERMENTATIVE MASH COOLING, HEATING, SAIGNÉE TECHNIQUE AND PROLONGED POST-FERMENTATIVE MACERATIONS

This study aimed to determine mineral composition in red wine obtained from cv. Teran (Vitis vinifera L.), autochtonous Croatian grape variety. Six different vinification treatments, including the control treatment (7-day standard maceration), were performed to study the effects of: 48-hour pre-fermentative mash cooling (8 °C) followed by prolonged post-fermentative maceration of 13 days (C15), 28 days (C30), and saignée technique (juice runoff) proceeded with prolonged post-fermentative maceration of 13 days (CS15); and effect of 48-hour heating (50 °C) followed by prolonged post-fermentative maceration of 13 days (H15) and 28 days (H30) on macro- and microelements in wine.

Read More

LARGE SURVEY OF THE CHEMICAL COMPOSITION OF WINES RESULTING OF THE PRESSING OF RED WINE MARC. FIRST RESULTS

In the Bordeaux vineyards, press red wine represents about 15% of the volume of wines. Valuing this large volume of press wine is necessary from an economic point of view, of course, but also because of their organoleptic contribution to the blend. Nevertheless, there is a lack of recent knowledge on the composition of press wines. This work aims to establish an initial assessment of their composition (aromatic and polyphenolic) and to set up hypothesis on to the links with their sensorial identity.

Read More

ANALYZING THE ROLE OF ELEMENTAL SULFUR IN GRAPE JUICE ON THE DEVELOPMENT OF POLYFUNCTIONAL MERCAPTANS IN SAUVIGNON BLANC WINES

Sauvignon blanc is characterized by distinctive aromas, both fruity and herbaceous. The “green” character has been attributed to the methoxypyrazines, while the “fruity” character is associated with polyfunctional mercaptans . Polyfunctional mercaptans are of great significance due to their high impact on wines and associated low perception thresholds.
Elemental sulfur (S⁰) is widely used to protect grapevines from powdery mildew.

Read More

EFFECT OF MICRO-OXYGENATION IN COLOR OF WINES MADE WITH TOASTED VINE-SHOOTS

The use of toasted vine-shoots (SEGs) as an enological tool is a new practice that seeks to improve wines, differentiating them and encouraging sustainable wine production. The micro-oxygenation (MOX) technique is normally combined with alternative oak products with the aim to simulate the oxygen transmission rate that takes place during the traditional barrel aging. Such new use for SEGs implies a reduction in color due to the absorption by the wood of the responsible compounds, therefore, given the known effect that MOX has shown to have on the modification of wine color, its use together with the SEGs could result in an interesting implementation with the aim to obtain final wines with more stable color over time.

Read More

EFFECT OF WHOLE BUNCH VINIFICATION ON THE ABUNDANCE OF A SWEETENING COMPOUND

In classic red wine-making process, grapes are usually destemmed between harvest and the filling of the vat. However, some winemakers choose to let all or a part of the stems in contact with the juice during vatting, this is called whole bunch vinification. For instance, this practice is traditionally used in some French wine regions, notably in Burgundy, Beaujolais and the Rhone Valley. The choice to keep this part of the grape is likely to affect the sensory properties of wine, as its gustatory perception1,2.

Read More