Macrowine 2021
IVES 9 IVES Conference Series 9 Ethyl esters interact with the major wine Thaumatin Like Protein VVTL1

Ethyl esters interact with the major wine Thaumatin Like Protein VVTL1

Abstract

The interactions among aromatic compounds and proteins is an important issue for the quality of foods and beverages. In wine, the loss of flavor after vinification is associated to bentonite treatment and this effect can be the result of the removal of aroma compounds which are bound wine proteins. This phenomenon was recently demonstrated for long chain fatty acids and their ethyl esters (1). Since these latter compounds are spectroscopically silent, their association with proteins is not easy to measure. Therefore, the binding of ethyl esters to a wine protein has been analyzed by studying the modifications of the protein structure (which indicates protein-ligand interactions) by Synchrotron Radiation Circular Dichroism (SRCD) spectroscopy (2). The effects induced by the addition of ethyl esters (from hexanoate to dodecanoate) on the secondary structure and stability of a purified Thaumatin like-protein (VVTL1), the most abundant wine protein, was studied in a wine model solution (12% ethanol, 5 g/l mesotartaric acid, pH 3.2). As demonstrated by UV-photo denaturation assays (20 repeated consecutive scans in the far UV-region of protein), the secondary structure of VVTL1 was only slightly affected by the presence of the selected aroma esters, but protein stability was increased by the addiction of octanoate, decanoate and dodecanoate ethyl esters. On the contrary, in the presence of ethyl hexanoate protein stability decreases. These data were further confirmed by SRCD thermal denaturation assay. The results here reported demonstrate that the content of ordered structure and the protein photo and thermal stability of the main wine protein VVTL1 is modified by ethyl esters of different chain length, indicating the existence of a binding phenomenon. Therefore esters interactions with proteins may occur in wine and that this fact can modulate both the effect of bentonite treatments and the perception of the wine aroma.

(1) Vincenzi et al., 2015. J. Agric. Food Chem., 63, 2314 (2) Hussain R. et al., 2012. Spectroscopic Analysis: Synchrotron Radiation Circular Dichroism, in: Comprehensive Chirality, 8, Elsevier, Amsterdam, pp. 438-448.

ACKNOWLEDGMENTS We thank Diamond Light Source for access to beamline B23 (SM8034) that contributed to the results presented here. This research has received funding from the European Community’s Seventh Framework Programme (FP7/2007-2013) under grant agreement nº 226716.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Poster

Authors

Andrea Curioni*, Diana Gazzola, Mattia Di Gaspero, Paolo Ruzza, Simone Vincenzi

*Università di Padova

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

Related articles…

Impact of non-fruity compounds on red wines fruity aromatic expression: the role of higher alcohols

A part, at least, of the fruity aroma of red wines is the consequence of perceptive interactions between various aromatic compounds, particularly ethyl esters and acetates, which may contribute to the perception of fruity aromas, specifically thanks to synergistic effects.1,2 The question of the indirect impact of non-fruity compounds on this particular aromatic expression has not yet been widely investigated. Among these compounds higher alcohols (HA) represent the main group, from a quantitative standpoint, of volatiles in many alcoholic beverages. Moreover, some bibliographic data suggested their contribution to the aromatic complexity by either increasing or masking flavors of wine, depending of their concentrations.

How do different oak treatment affect the sensory composition of Chenin blanc wines over time?

Wooden barrels have been the preferred method for oak maturation for wines, but the use of alternative oak products, such as staves and oak chips have increased in South Africa due to lower production costs. This study investigated the effect of different oak products used during fermentation and ageing on the sensory profile, degree of liking and perceived quality of a South African Chenin blanc wine. The different wine treatments included an unoaked tank control wine, wines matured in 5th fill barrels, wines matured in new barrels from three different cooperages, and wines matured in 5th fill barrels with stave inserts from two different cooperages.

Characterization of various groups of pyranoanthocyanins in Merlot red wine

In red wines, anthocyanins evolve during the wine-making process and ageing. They react with other compounds (such as vinylphenols, acetaldehyde, pyruvic acid…) to form a stable family of compounds called pyranoanthocyanins. Furthermore, the oxidation process can modify the anthocyanic profile of a red wine. It is also interesting to evaluate the occurrence of the different subclasses of pyranoanthocyanins and to characterize their chemical properties. The first objective of this study is to evaluate the occurrence of the different groups of pyranoanthocyanins in an oxidised Merlot wine by a centrifugal partition chromatography strategy. The second goal is to evaluate their relative impact in red wines from Bordeaux region by measuring their concentrations.

The challenge of quality in sulphur dioxide free wines: natural polyphenol alternatives

Sulphur dioxide (SO2) seems indispensable in winemaking because of its properties. However, a current increasing concern about its allergies effects in food product has addressed the international research efforts on its replacement. This supposes a sufficient knowledge of its properties and conditions of use. Several studies compared SO2 properties against new alternatives that are supposed to overcome SO2 disadvantages. Firstly, the state of art on SO2 wine replacements is revised, and secondly, the last promising results using natural enriched polyphenol extracts are shown.

Elicitors used as a tool to increase stilbenes in grapes and wines

The economic importance of grapevine as a crop plant makes Vitis vinífera a good model system to study the improvement of the nutraceutical properties of food products (Vezulli et al. 2007). Stilbenes in general, and trans-resveratrol in particular, have been reported to be responsible for various beneficial effects. Resveratrol´s biological properties include antibacteria and antifungal effects, as well as cardioprotective, neuroprotective and anticâncer actions (Guerrero et al. 2010 ). Stilbenes can be induced by biotic and abiotic elicitors since they are phytoalexins (Bavaresco et al. 2001).