Macrowine 2021
IVES 9 IVES Conference Series 9 Chemical and sensory diversity of regional Cabernet-Sauvignon wines

Chemical and sensory diversity of regional Cabernet-Sauvignon wines

Abstract

AIM: To investigate chemical and sensory drivers of regional typicity of Cabernet Sauvignon from different geographical regions of Australia.

METHODS: Commercial Cabernet wines (n = 52) from Coonawarra, Margaret River, and Yarra Valley Geographical Indications of Australia, and from Bordeaux, France, were selected for extensive chemical and sensory analysis.1 A range of analytical methods were optimised to quantify a comprehensive array of volatile compounds (> 70) originating from different sources, including grape, fermentation, oak maturation, and ageing. Along with basic chemical data, measurement of non-volatile compounds such as tannins and other secondary metabolites and elements was also undertaken. Multivariate statistical analysis using partial least squares regression was applied to the combined chemical data and the sensory analysis ratings obtained through a trained descriptive analysis panel of the same wines, to determine important compounds driving relevant sensory attributes.

RESULTS: The compound 1,4-cineole, described as ‘mint’ and ‘bay leaf’, was partly responsible for separation of the Cabernet Sauvignon wines from the Australian regions, particularly from Margaret River, whereas compounds such as 4-ethylphenol and 4-ethylguaiacol were linked to the aromas of ‘earthy’ and ‘yeasty’, which drove some of the separation of Bordeaux wines from the others. Varietal thiol, 3-mercapto-1-hexanol, which is mainly associated with Sauvignon Blanc and other white wine varieties, was measured in concentrations above its aroma detection threshold in all of the wines analysed, with similar concentrations present in Bordeaux and Coonawarra wines, and significantly higher concentrations in Margaret River and Yarra Valley wines. Additionally, non-volatiles such as particular elements drove some the separation between the regions; for example strontium was present in highest concentration in the Coonawarra wines and was found at lowest concentration in the Bordeaux wines. Free anthocyanins were also found to differ between Coonawarra and Bordeaux regions, with higher concentration being measured in the latter.

CONCLUSION

In determining the influential drivers of sensory properties of regional Cabernet Sauvignon wines, this study has uncovered various volatile and non-volatile constituents that are associated with specific sensory attributes. This is an important step in being able to define and subsequently help preserve the distinctive characters associated with regional Cabernet Sauvignon wines.

 

DOI:

Publication date: September 7, 2021

Issue: Macrowine 2021

Type: Article

Authors

Dimitra L. Capone 

Australian Research Council Training Centre for Innovative Wine Production, The University of Adelaide,Paul BOSS, CSIRO, and Australian Research Council Training Centre for Innovative Wine Production  Lira SOUZA GONZAGA, Australian Research Council Training Centre for Innovative Wine Production, and The University of Adelaide  Susan E. P. BASTIAN, Australian Research Council Training Centre for Innovative Wine Production, and The University of Adelaide Ruchira RANAWEERA, Department of Wine Science, The University of Adelaide David W. JEFFERY, Australian Research Council Training Centre for Innovative Wine Production, and The University of Adelaide

Contact the author

Keywords

volatile compound, non-volatile compound, sensory analysis, partial least squares regression, regionality, terroir

Citation

Related articles…

Differential responses of red and white grape cultivars trained to a single trellis system – the VSP

Commercial grape production relies on training grapevine cultivars onto a variety of trellis systems. Training allows for well-lit leaves and clusters, maximizing fruit quality in addition to facilitating cultivation, harvesting, and diseases control. Although grapevines can be trained onto an infinite variety of trellis systems, most red and white cultivars are trained to the standard VSP (Vertical Shoot Positioning) system. However, red and white cultivars respond differently to VSP in fruit composition and growth characteristics, which are yet to be fully understood. Therefore, the objective of this study was to examine the influence of the VSP trellis system on fruit composition of three red, Cabernet Sauvignon, Merlot and Syrah, and three white, Chardonnay, Riesling, and Gewurztraminer cultivars grown under uniform growing conditions in the same vineyard. All cultivars were monitored for maturity and harvested at their physiologically maximum possible sugar concentration to compare various fruit quality attributes such as Brix, pH, TA, malic and tartaric acids, glucose and fructose, potassium, YAN, and phenolic compounds including total anthocyanins, anthocyanin profile, and tannins. A distinct pattern in fruit composition was observed in each cultivar. In regards to growth characteristics, Syrah grew vigorously with the highest cluster weight. Although all cultivars developed pyriform seeds, the seed size and weight varied among all cultivars. Also varied were mesocarp cell viability, brush morphology, and cane structure. This knowledge of the canopy architectural characteristics assessed by the widely employed fruit compositional attributes and growth characteristics will aid the growers in better management of the vines in varied situations.

Analysis of Cabernet Sauvignon and Aglianico winegrape (V. vinifera L.) responses to different pedo-climatic environments in southern Italy

Water deficit is one of the most important effects of climate change able to affect agricultural sectors. In general, it determines a reduction in biomass production, and for some plants, as in the case of grapevine, it can endorse fruit quality. The monitoring and management of plant water stress in the vineyard

Current climate change in the Oplenac wine-growing district (Serbia)

Serbian autochthonous vine varieties Smederevka (for white wines) and Prokupac (for rosé and red wines) are the primary representatives of typical characteristics of wines and terroir of numerous wine-growing areas in Serbia. In the past, these varieties were the leading vine varieties, however, as the result of globalization of winemaking and the trend of consumption of wines from widely prevalent vine varieties, they were replaced by introduced international varieties. Smederevka and Prokupac vine varieties are characterized by later time of grape ripening, and relative sensitivity to low temperatures. Climate conditions can be a restrictive factor for production of high-quality grapes and wine and for the spatial spreading of these varieties in hilly continental wine-growing areas.
This paper focuses on the spatial analysis of changes of main climate parameters, in particular, analysis of viticultural bioclimatic indices that were determined for the purposes of viticulture zoning of wine-growing areas in the period 1961-2010, and those same parameters determined for the current, that is, referential climate period (1988-2017). Results of the research, that is, analysis of climate changes indicate that the majority of examined climate parameters in the Oplenac wine-growing district improved from the perspective of Smederevka and Prokupac vine varieties. These studies of climate conditions indicate that changes of analyzed climate parameters, that is, bioclimatic indices will be favorable for cultivation of varieties with later grape ripening times and those more sensitive to low temperatures, such as the autochthonous vine varieties Smederevka and Prokupac, therefore, it is recommended to producers to more actively plant vineyards with these varieties in the territory of the Oplenac wine-growing district.

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.

Traditional agroforestry vineyards, sources of inspiration for the agroecological transition of viticulture

A unique “terroir” can be found in southern Bolivia, which combines the specific features of climate, topography and altitude of high valleys, with the management of grapevines staked on trees. It is one of the rare remnants of agroforestry viticulture. A survey was carried out among 29 grapegrowers in three valleys, to characterize the structure and management of these vineyards, and identify the services they expect from trees. Farms were small (2.2 ha on average) and 85% of vineyards were less than 1 ha. Viticulture was associated with vegetable, fruit and fodder production, sometimes in the same fields. Molle trees were found in all plots, together with one or two other native tree species. Traditional grapevine varieties such as Negra Criolla, Moscatel de Alejandría and Vicchoqueña were grown with a large range of densities from 1550 to 9500 vines ha-1. From 18 to 30% of them were staked on trees, with 1.2 to 4.9 vines per tree. The management of these vineyards (irrigation, fertilization and grapevine protection) was described, the most particular technical operation being the coordinated pruning of trees and grapevines. Three types of management could be identified in the three valleys. Grapegrowers had a clear idea of the ecosystem services they expected from trees in their vineyards. The main one was protection against climate hazards (hail, frost, flood). Then they expected benefits in terms of pest and disease control, improvement of soil fertility and resulting yield. At last, some producers claimed that tree-staking was quicker and cheaper than conventional trellising. It can be hypothesized then that agroforestry is a promising technique for the agroecological transition of viticulture. Its contribution to the “terroir” of the high valleys of southern Bolivia and its link with the specificities of the wines and spirits produced there remain to be explored.