terclim by ICS banner
IVES 9 IVES Conference Series 9 VOLATILE COMPOSITION OF WINES USING A GC/TOFMS: HS-SPME VS MICRO LLE AS SAMPLE PREPARATION METHODOLOGY

VOLATILE COMPOSITION OF WINES USING A GC/TOFMS: HS-SPME VS MICRO LLE AS SAMPLE PREPARATION METHODOLOGY

Abstract

Wine aroma analysis can be done by sensorial or instrumental analysis, the latter involving several methodologies based on olfactometric detection, electronic noses or gas chromatography. Gas Chromato-graphy has been widely used for the study of the volatile composition of wines and depending on the detection system coupled to the chromatographic system, quantification and identification of individual compounds can be achieved.

Prior to the chromatography, a sample preparation step is almost always required, but unfortunately there is no extraction procedure that can aid in the detection of the wide range of volatile compounds that exists in a wine sample. Wine volatile profile is characterized to have thousands of compounds with varying chemical properties, like molecular weight, structure, polarity and molecular structures. Moreover, they exist in a wide range of concentration, which, sometimes implies that a pre-concentration step is also required, if the ones existing in very low concentrations are of interest. As far as sample preparation methods for the analysis of wine aroma concerns, one can found thousands of bibliographic references, but the most used ones are probably the liquid-liquid extraction (LLE) and the solid-phase microextraction (SPME). Extensive reviews on the different sample preparation methods that has been used for wine analysis, along with each one advantages and drawbacks, has already received researcher’s attention (Costa Freitas et al, 2012)

In light of the above, this work intents to discuss the use of two different sample preparation methods to quantify and identify volatile compounds in wines.

Two sample preparation methods were compared: a micro liquid-liquid extraction with 500mL of dichloromethane (based on Vilanova et al, 2010) and a HS-SPME (based on Pereira et al 2021). Chromatographic method was the same for both sample preparation method.

The number of compounds identified by HS-SPME was higher than the ones identified by micro-LLE. 26 compounds were identified in wines by both sample preparation methods. Since the majority of com-pounds identified by each sample preparation methodologies are different, choose to do one or another, or even both, should be taken into consideration when the goal is to go deep on volatile composition of wines.

 

1. M. Costa Freitas; M. D. R. Gomes da Silva; M. J. Cabrita (2012) “Sampling and sample preparation techniques for the determination of volatile components in grape juice, wine and alcoholic beverages” In Comprehensive Sampling and Sample Preparation. Volume 4, Pawliszyn J., Mondello L., Dugo P. Eds; Elsevier, Academic Press: Oxford, UK, pp 27–41, 2012. ISBN: 9780123813732
2. Singleton, V. e Rossi, J. (1965) Colorimetry of Total Phenolic Compounds with Phosphomolybdic-Phosphotungstic Acid Reagents. American Journal of Enology and Viticultura, 16, 144-158.
3. Mar Vilanova, Zlatina Genisheva, Antón Masa, José Maria Oliveira (2010). Correlation between volatile composition and sensory properties in Spanish Albariño wines. Microchemical Journal, 95, 240-246.
4. Pereira, C., Mendes, D., Dias, T., Garcia, R., da Silva, M. and Cabrita, M., 2021. Revealing the yeast modulation potential on amino acid composition and volatile profile of Arinto white wines by a combined chromatographic-based approach. Journal of Chromatography A, 1641, p.461991.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Nuno Martins¹, Maria João Cabrita1,2 Raquel Garcia1,2

1. MED—Mediterranean Institute for Agriculture, Environment and Development & CHANGE—Global Change and Sustainabi-lity Institute, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554 Évora, Portugal
2. Departamento de Fitotecnia, Escola de Ciências e Tecnologia, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554 Évora, Portugal

Contact the author*

Keywords

red wine, volatiles, sample preparation, GC/TOFMS

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

Metabolomics for grape and wine research: exploring the contributions of amino acids to wine flavour

A critical aspect of wine quality is the overall expression of wine flavour, which is formed by the interplay of volatile aroma compounds, their precursors, and taste and matrix components.
Grapes directly contribute to wine only a small number of potent aroma compounds, and the unique
sensory attributes and perceived quality of a wine result from combining 100s of metabolites of grapes, yeast and bacteria, and oak wood.

VOLTAMETRIC PROFILING OF RED WINE COMPOSITION DURING MACERATION: A STUDY ON FOUR GRAPE VARIETIES

During red wine vinification, maceration allows the must, and consequently the wine, to be enriched with several compounds that contribute to the creation of the typical organoleptic characteristics of red wines. Among these, extraction of polyphenols (PPs) during maceration is a major process of enological interest.
The purpose of this study was the evaluate the suitability of a rapid analytical approach based in linear sweep voltammetry to monitor PPs extraction during vinification.

UNEXPECTED PRODUCTION OF DMS POTENTIAL DURING ALCOOLIC FERMENTATION FROM MODEL CHAMPAGNE-LIKE MUSTS

The overall quality of aged wines is in part due to the development of complex aromas over a long period (1.) The apparition of this aromatic complexity depends on multiple chemical reactions that include the liberation of odorous compounds from non-odorous precursors. One example of this phenomenon is found in dimethyl sulphide (DMS) which, with its characteristic odor truffle, is a known contributor to the bouquet of premium aged wine bouquet (1). DMS supposedly accumulates during the ten first years of ageing thanks to the hydrolysis of its precursor dimethylsulfoniopropionate (DMSp.) DMSp is a possible secondary by-product from the degradation of S-methylmethionine (SMM), an amino acid iden- tified in grapes (2), which can be metabolized by yeast during alcoholic fermentation.

CONTRIBUTION OF VOLATILE THIOLS TO THE AROMA OF RIESLING WINES FROM THREE REGIONS IN GERMANY AND FRANCE (RHEINGAU, MOSEL, AND ALSACE)

Riesling wines are appreciated for their diverse aromas, ranging from the fruity fresh characters in young vintages to the fragrant empyreumatic notes developed with aging. Wine tasters often refer to Riesling wines as prime examples showcasing terroir, with their typical aroma profiles reflecting the geographical provenance of the wine. However, the molecular basis of the distinctive aromas of these varietal wines from major Riesling producing regions in Europe have not been fully elucidated. In this study, new lights were shed on the chemical characterization and the sensory contribution of volatile thiols to Riesling wines from Rheingau, Mosel, and Alsace. First, Riesling wines (n = 46) from the three regions were collected and assessed for their aroma typicality by an expert panel.

THE FLAVANOL PROFILE OF SKIN, SEED, WINES, AND POMACE ARE CHARACTERISTIC OF EACH TYPOLOGY AND CONTRIBUTES TO UNDERSTAND THE FLAVAN- 3-OLS EXTRACTION DURING RED WINEMAKING

Wine flavanols are extracted from grape skin and seeds along red winemaking. Potentially, eight flavan-3-ol subunits may be present as monomers or as tannins constituents, being these catechin, epicathechin, gallocatechin, epigallocatechin end the gallates of the mentioned units. In this work the flavanol profiles of grape skins and seeds before (grapes) and after (pomace) red winemaking were studied together with the one in the corresponding wines. The trials were made over two vintages in Vitis vinifera cv. Tannat, Syrah and Marselan from Uruguay.