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IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Optimization and validation of a fully automated HS-SPME method for determination of VCCs and its application in wines submitted to accelerated ageing

Optimization and validation of a fully automated HS-SPME method for determination of VCCs and its application in wines submitted to accelerated ageing

Abstract

Wine aroma is a complex gaseous mixture composed of various compounds; some of these molecules derive directly from the grapes while most of them are released and synthetized during fermentation or are due to ageing reactions. Among the latter class of compounds, carbonyls are the principal products of oxidation reactions which take place during the storing time. Volatile carbonyl compounds (VCCs) are related to aromatic nuances of vanilla, caramel, butter, honey, potato, orange, lemon, violets, cider and plum, which are pleasant scents characteristics of oxidized wines. However, apart from cases where it is a deliberate process, oxidation is commonly undesired and the presence of a relevant content of carbonyls is related to aroma defects. Because of that, monitoring the concentration of VCCs could be added as a quality control for the evaluation of a complete fermentation, correct winemaking style, and proper bottling and storage. In this research an HS-SPME method1 was optimized and validated with the aim to be used as a tool to achieve this goal. The use of a solvent-free extraction allowed to maximize the coherence to the Green Analytical Chemistry principles with a simultaneous achievement in performance, reliability and robustness. In this method, all sample preparation steps were automated using the autosampler minimizing the human time consumption to enhance the scalability to routine analysis. As many as 46 VCCs (mainly linear aldehydes, Strecker aldehydes, unsaturated aldehydes, ketones, and many other) were the analytes under investigation. All compounds showed a good linearity spanning from approximately 0.1 to 100 µg/L (R2>0.99). Intra-day and 5 days inter-days repeatability showed an RSD

DOI:

Publication date: June 23, 2022

Issue: IVAS 2022

Type: Article

Authors

Piergiovanni Maurizio1, Carlin Silvia2, Lotti Cesare2, Vhrovsek Urska2 and Mattivi Fulvio1,2

1Center Agriculture Food Environment (C3A), University of Trento, via Edmund Mach 1, San Michele all’Adige (TN) Italy
2Center Research and Innovation, Edmund Mach Foundation, Italy3Affiliation of the third 

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Keywords

Carbonyls, oxidation, accelerated ageing, HS-SPME, quality control

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IVAS 2022 | IVES Conference Series

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IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Optimization and validation of a fully automated HS-SPME method for determination of VCCs and its application in wines submitted to accelerated ageing

Optimization and validation of a fully automated HS-SPME method for determination of VCCs and its application in wines submitted to accelerated ageing

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Publication date: June 23, 2022

Issue: IVAS 2022

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Terroir analysis and its complexity

Terroir is not only a geographical site, but it is a more complex concept able to express the “collective knowledge of the interactions” between the environment and the vines mediated through human action and “providing distinctive characteristics” to the final product (OIV 2010). It is often treated and accepted as a “black box”, in which the relationships between wine and its origin have not been clearly explained. Nevertheless, it is well known that terroir expression is strongly dependent on the physical environment, and in particular on the interaction between soil-plant and atmosphere system, which influences the grapevine responses, grapes composition and wine quality. The Terroir studying and mapping are based on viticultural zoning procedures, obtained with different levels of know-how, at different spatial and temporal scales, empiricism and complexity in the description of involved bio-physical processes, and integrating or not the multidisciplinary nature of the terroir. The scientific understanding of the mechanisms ruling both the vineyard variability and the quality of grapes is one of the most important scientific focuses of terroir research. In fact, this know-how is crucial for supporting the analysis of climate change impacts on terroir resilience, identifying new promised lands for viticulture, and driving vineyard management toward a target oenological goal. In this contribution, an overview of the last findings in terroir studies and approaches will be shown with special attention to the terroir resilience analysis to climate change, facing the use and abuse of terroir concept and new technology able to support it and identifying the terroir zones.