OENO IVAS 2019 banner
IVES 9 IVES Conference Series 9 Can varietal ‘apricot’ aroma of Viognier wine be controlled with clonal selection and harvest timing?

Can varietal ‘apricot’ aroma of Viognier wine be controlled with clonal selection and harvest timing?

Abstract

Recent wine-like reconstitution sensory studies confirmed that several monoterpenes were the key aroma compounds in the perception of an ‘apricot’ aroma attribute in Viognier wine. Other aroma compounds, including a set of aldehydes and several γ-lactones, were also indicated to be related to ‘apricot’ aroma in that study, but the addition of these compounds to the reconstitution gave ambiguous results. 

To investigate these interactions, further reconstitution sensory studies were conducted. Firstly, in a wine-like model matrix, the aldehydes were found to suppress ‘apricot’ aroma intensity, while γ-lactones significantly enhanced the intensity of ‘apricot’, but only in the presence of a higher concentration of monoterpenes. Secondly, a neutral Chardonnay wine base spiked with the monoterpenes and γ-lactones together, or with only the monoterpenes added, was considered to have a similar ‘apricot’ aroma to a typical Viognier wine, whereas if spiked with only γ-lactones, then its aroma was not similar. Finally, a sensory difference study was conducted by comparing single or double strength γ-lactones in Chardonnay wine with added monoterpenes. No significant difference was found between the monoterpene-spiked Chardonnay wine and when γ-lactones were also added. Thus, γ-lactones are unlikely to impart or enhance ‘apricot’ aromas in white wine. 

Monoterpenes are grape-derived aroma compounds, but little is known regarding their accumulation in Viognier grapes. Having established the importance of monoterpenes to the perception of varietal ‘apricot’ aroma in Viognier wines, it is likely that controlling their concentration in the grapes can influence the ‘apricot’ aroma intensity in the resultant wine. 

To establish if clonal selection and harvest timing could be used as tools to modulate ‘apricot’ aromas in Viognier wines, vineyard studies were conducted. Eleven Viognier clones were assessed over three vintages. Large differences were found in the concentration of the monoterpenes between the clones. In a further study of four Viognier clones, two clones showed similar monoterpene concentration profiles throughout ripening, but the other clones were substantially lower in monoterpene concentration. Subsequently, a winemaking study was carried out to assess the effect of clone and grape ripeness on ‘apricot’ character in Viognier. Grapes from two Viognier clones were both picked at two ripening timepoints and from two wine regions with different climates.

Section for all references

DOI:

Publication date: June 19, 2020

Issue: OENO IVAS 2019

Type: Article

Authors

Tracey Siebert

The Australian Wine Research Institute, P.O. Box 197, Glen Osmond (Adelaide), SA, 5064, Australia

Contact the author

Keywords

List of different keywords (keyword1, keyword2, keyword3)

Tags

IVES Conference Series | OENO IVAS 2019

Citation

Related articles…

Photoselective shade films affect grapevine berry secondary metabolism and wine composition

Grapevine physiology and production are challenged by forecasted increases in temperature and water deficits. Within this scenario, photoselective overhead shade films are promising tools in warm viticulture areas to overcome climate change related factors. The aim of this study was to evaluate the vulnerability of ‘Cabernet Sauvignon’ grape berry to solar radiation overexposure and optimize shade film use for berry integrity. A randomized complete block design field study was conducted across two years (2020-2021) in Oakville, Napa Valley, CA, with four shade films (D1, D3, D4, D5) differing in the percent of radiation spectra transmitted and compared to an uncovered control (C0). Integrals for gas exchange parameters and mid-day stem water potential were unaffected by the shade films in 2020 and 2021. By harvest, berries from uncovered and shaded vines did not differ in their size or primary metabolism in either year. Despite precipitation exclusion during the dormant season in the shaded treatments, yield did not differ between them and the control in either season. In 2020, total skin anthocyanins (mg/g fresh mass) in the shaded treatments was greater than C0 during berry ripening and at harvest. Conversely, flavonol concentrations in 2020 were reduced in shaded vines compared to C0. The 2020 growing season highlighted the impact of heat degradation on flavonoids. Flavonoid concentrations in 2021 increased until harvest while flavonoid degradation was apparent from veraison to harvest in 2020 across shaded and control vines. Wine analyses highlighted the importance of light spectra to modify wine composition. Wine color intensity, tonality and anthocyanin values were enhanced in D4 whereas antioxidant properties were enhanced in C0 and D5 wines. Altogether, our results highlighted the need of new approaches in warm viticulture areas given the impact that composition of light has on berry and wine quality.

Study of varietal wines from the qualified origin denomination Rioja (Spain): analysis of wine colour, polysaccharides, polyphenols and biogenic amines and amino acides 

The cultivar with a greater oenological potential was ‘Monastel’, which showed overall better values than ‘Tempranillo’ in colour intensity, total polyphenol index, wine colour, total anthocyanins, resveratrol and gallic acid.

Progetto di zonazione delle valli di Cembra e dell’Adige. Analisi del comportamento della varietà Pinot nero in ambiente subalpino

Nel 1990 la Cantina LA VIS ha intrapreso un progetto di zonazione dei terreni vitati allo scopo di acquisire le conoscenze scientifiche atte a consentire il miglioramento delle qualità dei prodotti. Tale progetto si è articolato su di una superficie di 2000 ettari ubicati lungo l’asta fluviale del fiume Adige da Trento a Salorno e del torrente Avisio da Lavis a Segonzano.

The wine microbial ecosystem: Molecular interactions between yeast species and evidence for higher order interactions

Fermenting grape juice represents one of the oldest continuously maintained anthropogenic microbial environments and supports a well-mapped microbial ecosystem. Several yeast and bacterial species dominate this ecosystem, and some of these species are part of the globally most studied and best understood individual organisms. Detailed physiological, cellular and molecular data have been generated on these individual species and have helped elucidate complex evolutionary processes such as the domestication of wine yeast strains of the species Saccharomyces cerevisiae. These data support the notion that the wine making environment represents an ecological niche of significant evolutionary relevance. Taken together, the data suggest that the wine fermentation ecosystem is an excellent model to study fundamental questions about the working of microbial ecosystems and on the impact of biotic selection pressures on microbial ecosystem functioning. Indeed, and although well mapped, the rules and molecular mechanisms that govern the interactions between microbial species within this, and other, ecosystems remain underexplored. Here we present data derived from several converging approaches, including microbiome data of spontaneous fermentations, the population dynamics of constructed consortia, the application of biotic selection pressures in directed laboratory evolution, and the physiological and molecular analysis of pairwise and higher order interactions between yeast species. The data reveal the importance of cell wall-related elements in interspecies interactions and in evolutionary adaptation and suggest that predictive modelling and biotechnological control of the wine ecosystem during fermentation are promising strategies for wine making in future.

The colour pattern of flower arrangements influence wine tasters’ sensory description

The arrangements of flowers and wine counterparts are inextricably linked. Whether a fundamental aspect of tablescaping or acolytes to broader entertainment rituals, they have an entangled history since ancient times. The aim of this contribution is to verify the influence of visually delicate and robust flower arrangements on individual description of wines. Changes in the sensory description of wines were investigated during subjects’ (thirty-two participants) exposure to three different conditions: the presence of delicate, robust, or totally absent flower arrangements.