IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Effect of terroir and winemaking protocol on the chemical and sensory profiles of Pinot Blanc wine

Effect of terroir and winemaking protocol on the chemical and sensory profiles of Pinot Blanc wine

Abstract

Wine research in the past years has mainly been focused on laboratory scale due to the possibility of controlling winemaking variables. Conversely, studies on wine quality in relation to the winemaking variables at the winery scale may be able to better account for the actual challenges encountered during wine production. Winemaking problems are recently arising from progressive changes in environmental conditions in relation to the terroir. It is important to realize that each wine region may have specific winemaking protocols and that winemakers often base their decisions on subjective, emotional, and empirical opinions. Due to all the above-mentioned issues, taking the correct decision in winemaking to achieve the desired goals may become even more challenging. Hence, comprehensive analytical and sensory tools could provide substantial support for winemakers to base their decisions on data obtained from validated methodologies throughout the winemaking process. This report presents an example of a collaboration study on a winery-scale production of Pinot Blanc which has become an important production in South Tyrol (Italy) over the last decades, with its cultivation covering 10.3% of the total vineyards (www.altoadigewines.com). The main objective of the present project is to build a fingerprint database for wine identity (chemical and sensory data of Pinot Blanc in that area) to understand how terroir and winemaking practices are influencing the analytical and sensory/hedonic qualities of this wine, and to provide guidelines to winemakers accordingly to aid their decisions. 

The experimental plan for this study included factors such as (I) vineyard location, (II) pre-fermentation freezing of the grapes, and (III) simultaneous alcoholic and malolactic fermentations The samples were analyzed by HPLC-DAD for the determination of the phenolic compounds and by HS-SPME-GCxGC-ToF/MS for determining the volatile profiles. The sensory analysis was performed using Quantitative Descriptive Analysis (QDA ®) (Poggesi et al., 2021). The application of whole grape freezing in pre-processing turned out to be the main differentiating factor of the wines. The results also showed a strong dependence of the measured parameters on the vineyard which could be classified according to significantly different relative abundances of phenolic and volatile compounds. No difference was observed in the phenolic profile as a function of co-inoculation with malolactic bacteria. On the other hand, specific volatile compounds could differentiate samples undergoing simultaneous alcoholic and malolactic fermentation. The chemical results were then integrated with sensory data to create multivariate models, to show how the factors played out on the final quality of the wine obtained. Prospectively, fingerprint databases can be built on these models for authenticity purposes and to assist the winemaker during production.

References

• Alto Adige Wine – Exquisite Wines from Northern Italy (altoadigewines.com)
• Poggesi, S., Dupas de Matos, A., Longo, E., Chiotti, D., Pedri, U., Eisenstecken, D., & Boselli, E. (2021). Chemosensory Profile of South Tyrolean Pinot Blanc Wines: A Multivariate Regression Approach. Molecules, 26(20), 6245. https://doi.org/10.3390/molecules26206245
• Philipp, C., Eder, P., Sari, S., Hussain, N., Patzl-Fischerleitner, E., & Eder, R. (2020). Aromatypicity of Austrian Pinot Blanc Wines. Molecules, 25(23), 5705. https://doi.org/10.3390/molecules25235705
• Philipp, C., Eder, P., Brandes, W., Patzl-Fischerleitner, E., & Eder, R. (2018). The pear aroma in the Austrian Pinot blanc wine variety: evaluation by means of sensorial-analytical-typograms with regard to vintage, wine styles, and origin of wines. Journal of Food Quality, 2018. https://doi.org/10.1155/2018/5123280

DOI:

Publication date: June 27, 2022

Issue: IVAS 2022

Type: Poster

Authors

Darnal Aakriti1, Poggessi Simone1, Merkyte Vakare1, Longo Edoardo1, Montali Marco2 and Boselli Emanuele1

1Faculty of Science and Technology, Free University of Bozen-Bolzano
2Faculty of Computer Science, Free University of Bozen-Bolzano

Contact the author

Keywords

Pinot Blanc, wine identity, QDA, volatile profiles

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Impact of changes in pruning practices on vine growth and yield

A gradual decline in vineyards has been observed over the past twenty years worldwide. This might be explained by the climate change, practices change or the increase of dieback diseases. To increase the longevity of vines, we studied the impact of different pruning strategies in four adult and four young vineyards located in France and Spain. In France, vineyards were planted with Cabernet franc on 3309C while Spanish trials were planted with Tempranillo grafted on 110R. Vegetative expression, yield, quality of berries and wood vessels conductivity were measured. The distribution of vegetative expression, yield and berry composition between primary and secondary vegetation were quantified. Finally, tomography was used to evaluate the implication of the treatments on sap flows. First results show that i) the respectful pruning leads to an increase of 30 to 50% more secondary shoots than the aggressive pruning in France and between 15 and 20% in Spain, ii) there is no major effect on the yield over the first two years following the implementation of the new pruning practices, although the proportion of clusters from suckers is higher on the respectful pruning method. On young vines, the development of the trunk according to a respectful pruning leads to a loss of harvest 2 years after planting. This is due to the removal, on the future trunk, of the green suckers which carrying bunches. This operation carried out in spring rather than during winter pruning, would promote a better leaf / fruit balance when the plant comes into production, and could lead to better hydraulic conduction in the vessels of the trunk. Maintaining these trials for several years will provide more robust data to assess the impact of these practices on the vines over the long term.

Grapevine xylem embolism resistance spectrum reveals which varieties have a lower mortality risk in a future dry climate

Wine growing regions have recently faced intense and frequent droughts that have led to substantial economical losses, and the maintenance of grapevine productivity under warmer and drier climate will rely notably on planting drought-resistant cultivars. Given that plant growth and yield depend on water transport efficiency and maintenance of photosynthesis, thus on the preservation of the vascular system integrity during drought, a better understanding of drought-related hydraulic traits that have a significant impact on physiological processes is urgently needed. We have worked towards this end by assessing vulnerability to xylem embolism in 30 grapevine commercial varieties encompassing red and white Vitis vinifera varieties, hybrid varieties characterized by a polygenic resistance for powdery and downy mildew, and commonly used rootstocks. These analyses further allowed a global assessment of wine regions with respect to their varietal diversity and resulting vulnerability to stem embolism. Hybrid cultivars displayed the highest vulnerability to embolism, while rootstocks showed the greatest resistance. Significant variability also arose among Vitis vinifera varieties, with Ψ12 and Ψ50 values ranging from -0.4 to -2.7 MPa and from -1.8 to -3.4 MPa, respectively. Cabernet franc, Chardonnay and Ugni blanc featured among the most vulnerable varieties while Pinot noir, Merlot and Cabernet Sauvignon ranked among the most resistant. In consequence, wine regions bearing a significant proportion of vulnerable varieties, such as Poitou-Charentes, France and Marlborough, New Zealand, turned out to be at greater risk under drought. These results highlight that grapevine varieties may not respond equally to warmer and drier conditions, outlining the importance to consider hydraulic traits associated with plant drought tolerance into breeding programmes and modeling simulations of grapevine yield maintenance under severe drought. They finally represent a step forward to advise the wine industry about which varieties and regions would have the lowest risk of drought-induced mortality under climate change.

Biodiversity in the vineyard agroecosystem: exploring systemic approaches

Biodiversity conservation and restoration are essential for guarantee the provision of ecosystem services associated to vineyard agroecosystem such as climate regulation trough carbon sequestration and control of pests and diseases. Most of published research dealing with the complexity of the vineyard agroecosystems emphasizes the necessity of innovative approaches, including the integration of information at different temporal and spatial scales and development of systemic analysis based on modelling. A biodiversity survey was conducted in the Franciacorta wine-growing area (Lombardy, Italy), one of the most important Italian wine-growing regions for sparkling wine production, considering a portion of the territory of 112 ha. The area was divided into several Environmental Units (EUs), defined as a whole vineyard or portion of vineyard homogenous in terms of four agronomic characteristics: planting year, planting density, cultivar, and training system. In each EU a set of compartments was identified and characterised by specific variables. The compartments are meteorology, morphology (altitude, slope, aspect, row orientation, and solar irradiance), ecological infrastructures and management. The landscape surrounding EU was also characterised in terms of land-use in a buffer zone of 500 m. For each component a specific methodology was identified and applied. Different statistical approaches were used to evaluate the method to integrate the information related to different compartments within the EU and related to the buffer zone. These approaches were also preliminarily evaluated for their ability to describe the contribution of biodiversity and landscape components to ecosystem services. This methodological exploration provides useful indication for the development of a fully systemic approach to structural and functional biodiversity in vineyard agroecosystems, contributing to promote a multifunctional perspective for the all wine-growing sector.

Inhibition of Oenococcus oeni during alcoholic fermentation by a selected Lactiplantibacillus plantarum strain

The use of selected cultures of the species Lactiplantibacillus plantarum in Oenology has grown in prominence in recent years. While initial applications of this species centred very much around malolactic fermentation (MLF), there is strong evidence to show that certain strains can be harnessed for their bio-protective effects. Unwanted spontaneous MLF during alcoholic fermentation (AF), driven by rogue Oenococcus oeni, is a winemaking deviation that is very difficult to manage when it occurs. This work set out to determine the efficacy of one particular strain of Lactiplantibacillus plantarum(Viniflora® NoVA™ Protect), against this problem in Cabernet Sauvignon must. The work was carried out at commercial scale and in a winery environment and compared the bio-protective culture with the more traditional approach of reducing must pH by the addition of tartaric acid. The combination of both was also investigated. The concentration of both Oenococcus oeni and Lactiplantibacillus plantarum was determined using qPCR. The adventitious Oenococcus oeni showed the most growth during AF in the control wine, whereas in the wines treated with Lactiplantibacillus plantarum a bacteriostatic effect against this species was observed. This effect was comparable to the wines treated with tartaric acid. This has particular commercial relevance for controlling the flora in musts with high pH, or when the addition of tartaric acid is either not permitted or is prohibitive for other reasons.

austrianvineyards.com: online viewer of all designations of Austrian wine

To digitally record and present all the origins of Austrian wines in the same perfect and clear way was the motivation for the Austrian Wine Marketing Board (Austrian Wine) to start with the project in 2018. In June 2021 the results were presented to the public in an online viewer showing all the designations of Austrian wine, available at https://austrianvineyards.com in a largely barrier-free manner. The online viewer provides tailored individual maps fitted to the respective zoom level. The smallest unit of wine-origins in Austria is called Ried and is displayed in a plot-specific manner highlighting areas under vine. Information on the Ried include administrative district, winegrowing municipality, cadastral municipality, large collective vineyard site, specific winegrowing region, generic winegrowing region, winegrowing area and, in many cases, an illustrative picture. Complementary data on the size, elevation (minimum-maximum), orientation (in 8 sectors plus flat) and gradient (minimum, maximum, average) are based on the area under vine according to the EU’s Integrated Administration and Control System. Additional information covers climate data. The diagrams are taken from the monthly breakdown of data in the annals of the Central Institute for Meteorology and Geodynamics, Austria provide a display of values for air temperature, precipitation, and sunshine hours for the reference year and the long-term average. Seasonal aggregated data on temperature, precipitation, and sunshine hours complete the display. Short descriptions with emphasis on geology and soil, field name in historical maps, etymology of the denomination, and main planted variety complements the available information for the main designations in the online viewer. These descriptions are compiled by winegrowers, geologists, historians, and journalists. All the information and data can be extracted to a pdf-file. Printed vineyard maps are also available. Missing content regarding wine origins in Styria will be completed in winter 2021/22.