terclim by ICS banner
IVES 9 IVES Conference Series 9 LARGE SURVEY OF THE CHEMICAL COMPOSITION OF WINES RESULTING OF THE PRESSING OF RED WINE MARC. FIRST RESULTS

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

Abstract

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.

Measurements and dosages were done in 50 press wines and their associated free-run wines. Wines are monovarietal batch from: cabernet-sauvignon and merlot from Saint-Estèphe, Médoc, France. The vintage is 2021. The production of wines was done in the estate to the classical process. The grapes, picked up and harvested by hand, were destemmed, sorted using an optical sorter and crushed. During vinification, extractions were adapted to each batch by daily tastings. Maceration did not exceed 21 days. After pressing, the wines were kept in oak-barrels. Three months after pressing, all the wines were tasted and were categorized according to their aptitude to be incorporated in the blend of the premium wine. Samples were kept at 12°C in bottles.
For the study of the aromatic composition: dimethyl sulphide (DMS) and its precursors (HS-SPME-GC-MS); higher alcohols (GC-FID) and 33 esters (HS-SPME-GC-MS) were measured. Concerning the analysis of phenolic compounds: anthocyanin monomers (HPLC-UV) and flavonols (HPLC-fluo.) were determined. Indices such as IPT, CieLAB, pH, AT have also been measured.
As expected, the results showed a significant difference between the two grape varieties. For each grape variety, PCA suggest differences between the press wines and the drop wines for all compounds. For the aromatic compounds, total tannins and flavonols: the press wines are more concentrated than the free-run wines. There are no significant differences between the press and free-run wines concerning anthocyanins. More statistical analysis permits to highlight unexpected separation of compounds according to the pressing step. The data also highlight links between the composition and the sensorial categorization.
In conclusion, the study permits to propose a first molecular database and to explore the origins of the sensorial categorization of that wines.
The experiment is renewed during the 2022 harvest and new compounds are added to the database.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Margot Larose1,2; Michael Jourdes¹; Eric Boissenot³, Vincent Decup²; Stéphanie Marchand¹

1. ISVV-Univ. Bordeaux, Bordeaux INP, Bordeaux Sciences Agro, UMR 1366 OENOLOGIE, Bordeaux France
2. Château Montrose, Saint-Estèphe France
3. Laboratoire Boissenot, Lamarque, France

Contact the author*

Keywords

Press-wine, Phenolic composition, Aromatic composition, Sensorial categorization

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

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.

IN DEPTH CHARACTERIZATION OF OENOLOGICAL CHARACTERISTICS OF TWO LACHANCEA THERMOTOLERANS STARTER STRAINS

Non-Saccharomyces starter cultures became increasingly popular over the years because of their potential to produce more distinctive and unique wines. The major benefit of the use of Lachancea thermotolerans as a fermentation starter is its ability to produce relevant amounts of lactic acid and reduce alcoholic strength, making it valuable for mitigating negative impacts of climate change on grapes and wine quality. Besides, like any other non-Saccharomyces yeast, L. thermotolerans can significantly affect a whole range of other physico-chemical wine parameters.

HOW DOES ULTRASOUND TREATMENT AFFECT THE AGEING PROFILE OF AN ITALIAN RED WINE?

Many wine styles require moderate or extended ageing to ensure optimal consumer experience. However, few consumers have the interest or ability to age wine themselves, and holding wine in optimal conditions for extended periods is expensive for producers. A study was conducted on the use of ul-trasound energy on wine, with particular reference to its impact on sensory and chemical profiles. The OIV has authorised the use of ultrasound for processing crushed grapes (must) in Resolution OENO 616-2019, but not yet for finished wine1,2.

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.

THE IMPACT OF NON-SACCHAROMYCES YEASTS ON THE WHITE WINE QUALITY

Selected strains of non-Saccharomyces yeasts showed a positive effect on sensory characteristics and aromatic complexity of wine. A sequential microbial culture of non-Saccharomyces and S. cerevisiae species is usually inoculated due to poorer fermentability of non-Saccharomyces species. The aim of the study was to investigate the role of non-Saccharomyces yeasts in the production of white wines. We evaluated how individual combinations of sequential inoculations of non-Saccharomyces and S. cerevisiae species affect the aromatic compounds (volatile thiols and esters) and sensory characteristics of the wines.