IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Influence of oak species on the differentiation of aged brandies using chemometrics approach based on phenolic compounds UHPLC fingerprints

Influence of oak species on the differentiation of aged brandies using chemometrics approach based on phenolic compounds UHPLC fingerprints

Abstract

Oak is the main material used in cooperage for making barrels and wood chips destined to aged spirits and wines. Quercus alba L., Quercus petraea L. and Quercus robur L. are three of the most commonly used oak species in cooperage companies. The geographical origin and botanical species influence the composition of the wood and the subsequent impact on the sensory profile of the product aged in the wooden barrels. Depending on the type of oak in which the wines and spirits are aged, the final products obtained are very different. Phenolic compounds are the main components extracted from the wood during ageing, and they depend on many factors. Botanical species, toasting level, barrel dimension and ageing time are parameters that affect the type and amount of polyphenols that the wood releases into the wines and distillates.
Combining instrumental fingerprints with Chemometrics, known as fingerprinting methodology, is a novel strategy that allows information about the composition of brandy samples to be obtained in a non-selective way, as it is not necessary to identify or quantify the compounds present in the sample. Through a chemometric study of the instrumental fingerprint, it is possible to identify known or unknown areas of the chromatograms characteristic of a particular type of sample. Ultra-High-Performance Liquid Chromatography (UHPLC) was used to acquire the instrumental fingerprints of the phenolic profile at 280 nm and 320 nm of aged brandy samples. The chromatographic fingerprints of more than 100 samples of brandies produced from different distillates and aged in 350-litre barrels from three different oaks, Quercus alba L., Quercus robur L., and Quercus petraea L.; with two different degrees of toasting, medium and light; and during 14 and 28 months were recorded and pre-processed for the chemometric approach centred on patterns recognition.
Unsupervised patterns recognition techniques such as principal component analysis (PCA) and hierarchical cluster analysis (HCA) were applied. The results of these analyses revealed the influence of distillate type, ageing time and toasting level on the natural grouping of samples, being the first one the variable that most affects the natural grouping of samples. Nevertheless, for the same type of distillate, ageing time and toasting level, variables that influence the ageing process, groupings of the samples were observed depending on the type of wood in which they were aged. This methodology is very interesting, since it is not necessary to know or identify all the compounds that appear in the chromatographic profile to determine in this case, whether the brandy is aged in one or another type of oak. The application of the results obtained could lead in the future to a model for the discrimination/classification of brandies, based on the type of oak in which it is aged.

DOI:

Publication date: June 23, 2022

Issue: IVAS 2022

Type: Poster

Authors

Guerrero-Chanivet, María1,2, Ortega-Gavilán Fidel3, Bagur-González M. Gracia3, García-Moreno M. Valme1, Butrón-Benítez Daniel1,2, Guillén-Sánchez Dominico A.1 and Valcárcel-Muñoz Manuel J.2

1Department of Analytical Chemistry, Faculty of Science, IVAGRO, Campus of Puerto Real, University of Cádiz
2Bodegas Fundador, S.L.U.
3University of Granada

Contact the author

Keywords

Brandy, oak, ageing, fingerprint, phenolic compounds

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Modeling island and coastal vineyards potential in the context of climate change

Climate change impacts regional and local climates, which in turn affects the world’s wine regions. In the short term, these modifications rises issues about maintaining quality and style of wine, and in a longer term about the suitability of grape varieties and the sustainability of traditional wine regions. Thus, adaptation to climate change represents a major challenge for viticulture. In this context, island and coastal vineyards could become coveted areas due to their specific climatic conditions. In regions subject to warming, the proximity of the sea can moderate extremes temperatures, which could be an advantage for wine. However, coastal and island areas are particular prized spaces and subject to multiple pressures that make the establishment or extension of viticulture complex.
In this perspective, it seems relevant to assess the potentialities of coastal and island areas for viticulture. This contribution will present a spatial optimization model that tends to characterize most suitable agroclimatic patterns in historical or emerging vineyards according to different scenarios. Thanks to an in-depth bibliography a global inventory of coastal and insular vineyards on a worldwide scale has been realized. Relevant criteria have been identified to describe the specificities of these vineyards. They are used as input data in the optimization process, which will optimize some objectives and spatial aspects. According to a predefined scenario, the objectives are set in three main categories associated with climatic characteristics, vineyards characteristics and management strategies. At the end of this optimization process, a series of maps presents the different spatial configurations that maximize the scenario objectives.

Late frost protection in Champagne

Probably one of the most counterintuitive impacts of climate change on vine is the increased frequency of late frost. Champagne, due to its septentrional position is historically and regularly affected by this meteorological hazard. Champagne has therefore developed a strong experience in frost protection with first experiments dating from the end of 19th century. Frost protection can be divided in two parts: passive and active. Passive protection includes all the methods that do not seek to modify the vine’s environment or resistance at the time of frost. The most iconic passive protection in Champagne is the establishment of the individual reserve. This reserve allows to stock a certain quantity of clear wine during a surplus year to compensate a meteorological hazard like frost during the following years. Other common passive methods are the control of planting area (walls, bushes, topography), the choice of grape variety, late pruning, or the impact of grass cover and tillage. Active frost protection is also divided in two parts. Most of the existing techniques tend to modify vine’s environment. Most of the time they provide warmth (candles, heaters, windmills, heating cables…), or stabilise bud’s temperature above a lethal threshold (water sprinkling). The other way to actively fight is to enhance the resistance of buds to frost (elicitors). The Comité Champagne evaluates frost protection methods following three main axes: the efficiency, the profitability, and the environmental impact through a lifecycle assessment. This study will present the results on both passive and active protection following these three axes.

Spatial determination of areas in the Western Balkans region favorable for organic production

In problematic conditions for production of grapes and wine caused by the COVID-19 pandemic and the resulting occurrence of wine surpluses, producers are increasingly turning to the innovative viticulture and winemaking of products that are more appealing to the market and the consumers. On the other hand, consumption of the food safety or organic products, and therefore of organic grapes and wine, is increasingly common in the world, in particular in Europe. The Regional Rural Development Standing Working Group (SWG RRD), as a regional intergovernmental organization gathers actors in the viticulture and winemaking sector from states and territories of the Western Balkans (South-East Europe) in the Expert Working Group for Wine, with the aim of improving viticulture and winemaking in this region through joint activities. In accordance with the aforementioned, the SWG RRD is working on advancing organic production of grapes and wine, and on recognition of specificities of the terroir of wine-growing areas in Western Balkans. In addition, as part of the project “Facilitation of Exchange and Advice on Wine Regulations in Western Balkan Countries” helmed by the German Federal Ministry of Food and Agriculture, in addition to harmonization of relevant legislation with EU regulations, efforts are being invested towards recognition of organic wines. Within activities and project implemented by this organization, expert analyses and scientific research of the terroir of Western Balkans were carried out, and some of the results are presented in this paper.

δ13C : A still underused indicator in precision viticulture  

The first demonstration of the interest of carbon isotope composition of sugars in grapevine, as an integrated indicator of vineyard water status, dates back to 2000 (Gaudillère et al., 1999; Van Leeuwen et al., 2001). Thanks to the isotopic discrimination of Carbon that takes place during plant photosynthesis, under hydric stress conditions, it is possible to accurately estimate the photosynthetic activity. Ever since, δ13C has been widely applied with success to zonation, terroir studies and vine physiology research, but is still not widely used by viticulturists. This is quite astonishing by considering the impact of global warming on viticulture and the need to improve water management, that would justify a widespread use of δ13C.
The lack of private laboratories proposing the analysis, the cost of the technology, as well as the long analytical delays, have been detrimental to its development. Some laboratories tried to overcome the analytical difficulties of isotopic analysis by using fourier transformed infrared spectroscopy, as a fast and cheap alternative to the official OIV method (IRMS). These claimed FTIR models have never been published or peer reviewed and cannot be considered robust. In this work, thanks to the recent acquisition of IRMS technology, new modern and robust applications of δ13C for viticulture are proposed. This includes the use of the analysis to make parcel separations at harvesting, the possibility to increase the precision of hydric stress cartography and the potential cost reduction when compared with Scholander pressure bomb analysis.

Assessment of climate change impacts on water needs and growing cycle on grapevine in three DOs of NE Spain

This study assessed the suitability of grapevine growing in three DOs (Empordà, Pla de Bages and Penedès) of Catalonia (NE Spain) over the 21st century. For this purpose, an estimation of water needs and agroclimatic and phenological indicators was made. Climate change impacts were estimated at 1 km pixel resolution using temperature and precipitation projections from several general circulation models (GCM) and two climate change scenarios: RCP 4.5 (stabilization scenario) and RCP 8.5 (worst-case scenario). Potential crop evapotranspiration (following FAO procedure) and a daily water balance considering soil water holding capacity were used to estimate actual evapotranspiration of vines and, finally, water needs. Dynamics would be similar in the three DOs studied although the magnitude of impact differs. Water needs would be 2 and 3 times greater (ranging from 0 to more than 1500 m3/ha) than current water needs at both climate change scenarios. Moreover, blooming date would advance from 3 to 6 weeks, harvest date from 1 to 2.5 months, resulting in growing cycles from 10 to 80 days shorter. It should also be noted that frost risk would decrease from 6 to 76%, the number of days with temperatures above 30ºC during ripening would rise from 48 to 500% and tropical nights (minimum temperature >20ºC) at ripening would increase from 28 to 150%, depending on the scenario and the DOs. The impacts of climate change in the three DOs could result in significant limitations for grapevine cultivation and wine production if adaptive strategies are not applied. This result could serve as a basis for the design of specific and particular adaptation strategies to improve and maintain vineyards in the DOs studied and could be extrapolated to similar DOs and regions.