Macrowine 2021
IVES 9 IVES Conference Series 9 DNA and type of grain: which factor does better explain sensory differences of sessile and pedunculate oaks?

DNA and type of grain: which factor does better explain sensory differences of sessile and pedunculate oaks?

Abstract

Sessile oak and pedunculate oak have shown several differences of interest for enological purposes. Tannic and aromatic composition among sessile oak or pedonculate oak has been well studied. Sessile oak is generally more aromatic than pedunculated, while the later is more tannic. This scientific point of view is rarely applied to classify oak in cooperages. Most coopers use the type of grain to distinguish wide and thin grain. While the former leads to barrels with less aromas and more tannins, often oriented to alcohols, the later is more aromatic and convenient for wine ageing. Does the traditional cooper grading by grain have a link with species in the chemical expression of oak? A protocol has been built to monitor the effect of the two species from the tree to the barrel, and the wine aged in them. In this study the first results observed during the yard seasoning are presented. Several oak trees from the same plot in the Forêt Domaniale de Saint Palais, France were studied. Recent developments of DNA tests can identify oak species or hybrid (instead of morphological determination that can be approximate). DNA tests were performed on each tree to identify their species. After excluding hybrids, only pure sessile oak and pure pedunculate oak were considered and separated into two batches. Staves were split from each oak batch, classified according to their type of grain and put in the yard for 24 months of seasoning. Chemical, sensory and also wood microflora analyses have been made at the beginning (T0), after 6 months (T6), after 12 months (T12) and after 18 months (T18) of seasoning. Among the sessile oak, two groups can be distinguished. The former is extremely rich in lactones whereas the later is poorer and can be considered as a “neighbor” of pedunculate oak that is poor in lactones but richer in tannins. Pedunculate oak is homogeneous whether its grain is tight or wide. Sessile oak seems to be impacted by the type of grain. The richer group is related to only thin grain while the poorer is made of mainly wide grain. Tastings on oak shavings showed that sessile oak has spicy, fresh and pastry aromas whereas pedunculate oak was acetic. Moreoever the later showed a more important and varied microflora. These first three steps of the yard seasoning have shown that the grain have a true effect on the aromatic composition of sessile oak. Are these differences kept along yard seasoning, barrel making and wine ageing?

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Poster

Authors

Marie Mirabel*, Rémi Teissier du Cros, Vincent Renouf

*Chêne & Cie

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

Related articles…

Intelligent article to control the internal pressure in continue in bottles

An intelligent packaging might, among others, provide information and allow monitoring of the quality of the packed product or its surrounding environment. A recent project on micro-flow wine bottles closed with aluminium screw cap and tightness liner, highlighted the importance of monitoring the internal overpressure continuously, in real-time and at least for 72 hours, since the internal pressure on the tightness liner and the micro-flow are related. Real-time and continuous measurements are not the standard methods of measurement of the overpressure, yet. The most used equipment for the determination of the pressure in wine bottle is the aphrometer, a destructive device that supplies a single value of pressure.

Partial dealcoholisation of red wine by reverse osmosis-evaporative perstraction: impact on wine composition

Around the world, the alcohol content of wine has been steadily increasing; partly as a consequence of climate change, but also due to improvements in viticultural management practices and winemaking techniques [1,2]. Concurrently, market demand for wines with lower alcohol levels has increased as consumers seek to reduce alcohol intake for social and/or health reasons [3]. As such, there is increasing demand for both innovative methods that allow winemakers to produce ‘reduced alcohol wines’ (RAW) and a better understanding of the impact of such methods on the composition of RAW. This study therefore aimed to investigate compositional changes in two red wines resulting from partial alcohol removal following treatment by one such method, involving a combination of reverse osmosis and evaporative perstraction (RO-EP).

Elicitors used as a tool to increase stilbenes in grapes and wines

The economic importance of grapevine as a crop plant makes Vitis vinífera a good model system to study the improvement of the nutraceutical properties of food products (Vezulli et al. 2007). Stilbenes in general, and trans-resveratrol in particular, have been reported to be responsible for various beneficial effects. Resveratrol´s biological properties include antibacteria and antifungal effects, as well as cardioprotective, neuroprotective and anticâncer actions (Guerrero et al. 2010 ). Stilbenes can be induced by biotic and abiotic elicitors since they are phytoalexins (Bavaresco et al. 2001).

Prediction of the production kinetics of the main fermentative aromas in alcoholic fermentation

Fermentative aromas (especially esters and higher alcohols) highly impact the organoleptic profile of young and white wines. The production of these volatile compounds depends mainly on temperature and Yeast Available Nitrogen (YAN) content in the must. Available dynamic models predict the main reaction
(bioconversion of sugar into ethanol and CO2 production) but none of them considers the production kinetics of fermentative aroma compounds during the process of fermentation. We determined the production kinetics of the main esters and higher alcohols for different values of initial YAN content and temperature, using an innovative online monitoring Gas Chromatography device.

Influence of inactive dry yeast treatments during grape ripening on postharvest berry skin texture parameters and phenolic compounds extractability

Inactive dry yeast treatments in the vineyard are a tool used with the aim to improve the concentration and quality of secondary metabolites in grapes, leading to a better differentiation of the wines made from grapes differently treated. In this work, a foliar spraying treatment with yeast derivatives specifically designed to be used with the patent pending application technology of Lallemand Inc. Canada (LalVigne® Mature, Lallemand Inc., Montreal, Canada) was tested on Vitis vinifera L. cv. Barbera and Nebbiolo black winegrapes. The aim was to evaluate the effect of this treatment on the phenolic compounds accumulation, the skin physical-mechanical properties and the related phenolic extractability. Prior to analysis, the berries were sorted by flotation in order to evaluate their distribution by density class, and to determine the skin texture parameters of berries with different sugar contents, thus understanding also the ripening effect.