Terroir 2006 banner
IVES 9 IVES Conference Series 9 The role of œnology in the enhancement of terroir expression

The role of œnology in the enhancement of terroir expression

Abstract

The reality of terroir is reflected by the typicality that it confers on the wine. The relationship between the origin of wine and its quality did already exist before the appearance of œnological science. Producers and merchants have always tried to improve wine quality in order to satisfy their clients. Before being scientific, this approach was empirical. Grands Crus emerged in Bordeaux when wine could be aged thanks to the development of techniques like disinfecting barrels with sulphur candles, racking, topping up and bottling with cork stoppers. Pasteur was the founder of the oenological science. He had a scientific, but also very practical approach. In the 1930’s, the application of the knowledge about pH, oxydo-reduction and colloids to wine production improved stabilisation of wines. The principles of modern red wine vinification and control over malolactic fermentation were first established in Bordeaux Grand Crus in the 1950’s-1960’s, before being internationally adopted. In the 1980 the œnological science progressed in the understanding and the control of alcoholic fermentation. Today, the role of nitrogen, lipids, temperature and oxygen are well understood. Knowledge about yeast genetics helped to select yeasts for various styles of wines. Off flavours in wines are better controlled since the molecules that are involved have been identified. Wine typicality is, among other factors, determined by its aromatic profile. Wines aromas can be different than the aromas in the grapes from which the wine was produced. The understanding of white wine aromas progressed over the last years, but a lot of work has still to be done on red wine aromas. Tannin quality is also a field that is not yet well explained by oenological science. Œnology should not lead to produce uniform « fast wines », but help to produce original and typical wines, for the pleasure of the amateurs and the profitability of wine producing and distributing companies.

DOI:

Publication date: January 12, 2022

Issue: Terroir 2006

Type: Article

Authors

Denis DUBOURDIEU

Faculté d’œnologie, Université Victor Ségalen Bordeaux 2, 351, cours de la Libération 33405 Talence, France
Institut des Sciences de la Vigne et du Vin de Bordeaux

Keywords

oenology, terroir, aroma, yeast, typicality

Tags

IVES Conference Series | Terroir 2006

Citation

Related articles…

Ten grapevine rootstocks: effects on vegetative development, production and grape quality of cv. Mencia in the d.o. Bierzo (Spain)

Grapevine rootstock is basic to achieve good adaptation of the vine to ground and environment.

Evaluation of vineyards, fruit and wine affected by wild fire smoke

Wineries may randomly reject fruit from vineyards near wild fires exposed to smoke. It is difficult to determine if fruit has been compromised in quality when exposed to smoke

Evaluation of wood starch content on bench grafting success rate in grapevine

Since the emergence of phylloxera, grafting has been the most used propagation method in viticulture. Despite all the improvement measures implemented in the nurseries, it is frequent that graft success rates vary depending on the nursery process and scion/rootstock combinations. The reasons behind this unsatisfactory behaviour are still unknown and can be diverse, although carbohydrate reserves might be hypothesised to be crucial, since callus, root, and new tissue formation will be built based on them. In order to identify the effect of carbohydrates on grafting success, nine combinations were established based on the starch content in grapevine scionwoods (cv. Tempranillo clone VN69) and rootstocks cuttings (110 Richter clone 237) used for grafting: Low (L), Medium (M), High (H).

Late season canopy management practices to reduce sugar loading and improve color profile of Cabernet-Sauvignon grapes and wines in the high irradiance and hot conditions of California Central Valley

Global warming is accelerating grape ripening, leading to unbalanced wines from fruit with high sugar content but poor aroma and colour development. Reducing the size of the photosynthetic apparatus after veraison has been shown to delay technological ripeness in cool climates, but methods have not been tested in areas with high irradiance and temperature where fruit exposure could have disastrous effects on berry composition. In this Cabernet-Sauvignon trial, we compared the application of an antitranspirant (pinolene), to severe canopy topping and above bunch zone leaf removal, all performed at mid-ripening, with an untouched control. We monitored the vines weekly by measuring stem water potential, gas exchange, fruit zone light exposure. We sampled berries to measure berry weight, total soluble solids, pH, titratable acidity, and the anthocyanin profile. At harvest, we assessed yield components, measured carbon isotope discrimination, rated sunburn on clusters, and produced experimental wines. We submitted harvest samples to metabolomic profiling through PFP-Q Exactive MS/MS and wines to sensory analysis. Application of the antitranspirant significantly reduced stomatal conductance and assimilation rate but did not affect the stem water potential. Inversely, leaf removal and topping increased water potential but did not affect leaf gas exchange. The late topping was the only treatment able to decrease sugar content (up to 2Bx), increase titratable acidity and pH, and improve anthocyanin content because of lower degradation of di-hydroxylated forms. Late leaf removal above the bunch zone increased lightning conditions in the canopy and produced the most significant damage on fruits. Yield components were not affected. This work suggests that late-season canopy management can effectively control ripening speeds and improve grapes and wines. Still, the effect on grape exposure in a critical time must be well balanced to avoid problems with the appropriate technique.

Effect of alcoholic strength on the phenolic and furfural compounds of Brandy de Jerez aged in Sherry Casks®

Brandy is a spirit drink produced from wine spirit aged for at least six months in oak casks with a capacity of less than 1000 L and minimum alcohol by volume (ABV) of 36%. During the aging process, physicochemical and sensory changes take place. Manifested by colour, flavour or aroma variations that improve the quality of the initial distillate.