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…

A preliminary study of clonal selection in cv. Viura in relation to varietal aroma profile

Viura is a synonym for Macabeo and currently it is the most widely planted white grape variety in D.O.Ca. Rioja, with 3,569 ha, representing 84% of the white grape cultivated area. It is a generous-yielding grape, presenting low values of titratable acidity and with large and compact clusters which makes it susceptible to Botrytis cinerea. Thus, this variety not always satisfies the wine grower’s prospects. Nowadays, the available plant material is scarce, moreover, it was selected on the basis of other quality criteria, not currently requested.

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.

New acylated flavonols identified in the grape skin of Vitis vinifera cv. Tannat and their wines

Flavonols are a class of flavonoid compounds derived from plant secondary metabolism. There they play different roles like antioxidants, internal regulators and UV screenings. In red wines, flavonols have increasingly received consideration by part of scientific and winemakers according their properties began to arise known. Among these stand out wine colour stabilization and their value as bioactive compounds. In this work the complete series of the acetylated and p-coumaroylated derivatives of the 3-O-glycosides of methoxylated flavonols, namely isorhamnetin, laricitrin and syringetin, have been identified in grapes and their respective wines from Vitis vinifera cv. Tannat.

Sensory impacts of the obturator used for the Chasselas: study over the time

Many parameters affect the organoleptic characteristics of wine: internal parameters like the chemical composition or polyphenol content and external as for example storage conditions or the type of obturator. The aim of this study was to characterize sensorally the impacts of several type of obturator on a white wine: Chasselas. To determine the organoleptic characteristics of this wine, a quantitative descriptive analysis could be used. But rapid sensory methods were preferred in this project. Indeed these methods are an appropriate alternative to conventional descriptive methods for quickly assessing sensory product discrimination.

Effect of different foliar nitrogen applications on the must amino acids and glutathione composition in Cabernet Sauvignon vineyard

Cabernet Sauvignon is one of the most important winegrape varieties in Chile. However, temperature raise and decreased rainfall due to climate change can lead to grape quality decrease in certain areas. Amino acids are essential as nitrogen source for yeast but also directly affect grape quality serving as precursors of certain volatile compounds that enhance the wine bouquet. Besides, glutathione is an important tripeptide acting as antioxidant, preventing the appearance of browning pigments in must and exerts a protective effect in volatile compounds.