terclim by ICS banner
IVES 9 IVES Conference Series 9 NEW METHOD FOR THE QUANTIFICATION OF CONDENSED TANNINS AND OTHER WINE PHENOLIC COMPOUNDS USING THE AUTOMATED BIOSYSTEMS SPICA ANALIZER

NEW METHOD FOR THE QUANTIFICATION OF CONDENSED TANNINS AND OTHER WINE PHENOLIC COMPOUNDS USING THE AUTOMATED BIOSYSTEMS SPICA ANALIZER

Abstract

Wine phenolic compounds are important secondary metabolites in enology due to their antioxidant and nutraceutical properties, and their role in the development of color, taste, and protection of wine from oxidation and spoilage. Tannins are valuable phenolic compounds that contribute significantly to these wine properties, especially in mouthfeel characteristics; however, tannin determination remains a significant challenge, with manual and time-consuming methods or complex methodologies. The purpose of this study is to propose a novel method for quantifying condensed tannins in finished wine products. This method aims to provide an accurate approximation of condensed tannin levels, similar to the widely used precipitation assay that involves the polysaccharide polymer methyl cellulose. The new tannin approximation is based on the strong correlation observed between Total Polyphenol Index (TPI) and methyl cellulose precipitable (MCP) tannin assay as both are determined at 280 nm, and using the epicatechin calibration is possible to obtain a value that is equivalent to condensed tannins determined by MCP tannin assay. Thus far, the results have shown a strong correlation between this new method and MCP tannin assay, with an r2 value of 0.83 and a sample size of 60. The present study has included wines from diverse geographical locations and varying ages. In addition to quantifying condensed tannins, the study also aimed to explore potential correlations that may explain differences found in the wines by analysing other polyphenolic parameters. These parameters included catechins determined via the DMACA reaction, anthocyanins based on their structural transformation arising from a change in pH, total polyphenols measured using the Folin-Ciocalteu reaction, TPI, and the chromatic features of wines at 420, 520 and 620 nm. Moreover, the study incorporated analyses of pH, total acidity, and ethanol content to obtain a comprehensive understanding of the wines’ chemical composition. Noteworthy, the study is expanding the sampling to consider more matrices within the winemaking process.

All of the aforementioned parameters, including the condensed tannin, were determined automatically using the BioSystems SPICA® analyzer. The technical simplicity of automated methods for phenolic evaluation, will lead to enhanced efficiency, robustness, and accuracy. Furthermore, these automated methods may facilitate greater field applications, leading to increased profitability and an opportunity to improve wine quality.

 

1. Vignault A, González-Centeno MR, Pascual O, Gombau J, Jourdes M, Moine V, et al. Chemical characterization, antioxidant properties and oxygen consumption rate of 36 commercial oenological tannins in a model wine solution. Food Chem. 2018 Dec 1;268:210–9.
2. Gutiérrez-Escobar R, Aliaño-González MJ, Cantos-Villar E. Wine polyphenol content and its influence on wine quality and properties: A review. Vol. 26, Molecules. MDPI AG; 2021.
3. Ribereau-Gayon P, Glories Y. Handbook of Enology:The Chemistry of Wine Stabilization and Treatments. 2006.
4. Habertson J, Spayd S. Measuring Phenolics in the winery. Am J Enol Vitic. 2006;57(3).

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Marilyn M. García-Tenesaca¹, Andreu Tobeña Montanuy²

1. Biosystems S.A , Costa Brava 30, Barcelona, Spain

Contact the author*

Keywords

Tannins, Polyphenolic profile, Automated methods, Wine

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

THE POTENTIAL USE OF SOLUBLE POLYSACCHARIDES TO PREVENT THE OXIDATION OF ROSÉ WINES

Lately, rosé wine is rapidly increasing its popularity worldwide. Short-time macerations with the red skin of the grapes cause the partial extraction of anthocyanins, which are responsible for the pinki-sh-salmon hue of rosé wines. However, the low quantity of tannins (antioxidants) and richness in phenolic acids, which can be easily oxidized into yellowish pigments, tend to predispose rosé wines to an undesirable browning. Although the use of SO₂ for the prevention of oxidation is highly extended, this practice is expected to be reduced. Therefore, the search for alternative oenological adjuvants that prevent the oxidation and browning of rosé wines is highly desired.

REMEDIATION OF SMOKE TAINTED WINE USING MOLECULARLY IMPRINTED POLYMERS

In recent years, vineyards in Australia, the US, Canada, Chile, South Africa and Europe have been exposed to smoke from wildfires. Wines made from smoke-affected grapes often exhibit unpleasant smoky, ashy characters, attributed to the presence of smoke-derived volatile compounds, including volatile phenols (which occur in free and glycosylated forms). Various strategies for remediation of smoke tainted wine have been evaluated. The most effective strategies involve the removal of smoke taint compounds via the addition of adsorbent materials such as activated carbon, which can either be added directly or used in combination with nanofiltration. However, these treatments often simultaneously remove wine constituents responsible for desirable aroma, flavour and colour attributes.

WINE AS AN EMOTIONAL AND AESTHETIC OBJECT: IMPACT OF EXPERTISE

Wine tasting has been shown to provide emotions to tasters (Coste et al. 2018). How will expertise impact this emotional response? Burnham and Skilleås (2012) reported that the cultural, experiential, and aesthetic competencies characterize an expert in wine compared to a novice. Although there is no consensual definition of an aesthetic experience, Burnham and Skilleås (2012) reported that aesthetic appreciation is “disinterested, normative for others and communicable” in comparison to sensory pleasure.

IMPACT OF METSCHNIKOWIA PULCHERRIMA DURING FERMENTATION ON AROMATIC PROFILE OF VIDAL BLANC ICEWINE

Non-Saccharomyces yeasts not only increase microbial diversity during wine fermentation, but also have a positive effect on improving wine aroma. Among these non-Saccharomyces yeast species, Metschnikowia pulcherrima is often studied and used in winemaking in recent years, but its application in icewine has been rarely reported. In this study, indigenous M. pulcherrima strains and Saccharomyces cerevisiae strains (commercial and indigenous strains) were sequentially inoculated for icewine fermentations; meanwhile, pure S. cerevisiae fermentations were used as the control; indigenous strains used above were screened from spontaneous fermentations of Vidal blanc icewine.

HOW DOES ULTRASOUND TREATMENT AFFECT THE AGEING PROFILE OF AN ITALIAN RED WINE?

Many wine styles require moderate or extended ageing to ensure optimal consumer experience. However, few consumers have the interest or ability to age wine themselves, and holding wine in optimal conditions for extended periods is expensive for producers. A study was conducted on the use of ul-trasound energy on wine, with particular reference to its impact on sensory and chemical profiles. The OIV has authorised the use of ultrasound for processing crushed grapes (must) in Resolution OENO 616-2019, but not yet for finished wine1,2.