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…

Metabolomic profile of red non-V. vinifera genotypes

Vitis vinifera L. is the most widely cultivated Vitis species which includes numerous cultivars. Owing to their superior quality of grapes, these cultivars were long considered the only suitable for the production of fine wines. However, the lack of resistance genes in V. vinifera against major grapevine pathogens, requires for its cultivation frequent spraying with large amount of fungicides. Thus, the search for alternative and more sustainable methods to control the grapevine pathogens have brought the breeders to focus their attention on other Vitis species. In fact, wild Vitis genotypes present multiple resistance traits against pathogens, such as powdery mildew, downy mildew and phylloxera.

Identification, quantification and organoleptic impact of « dried fruit » molecular markers in Merlot and Cabernet Sauvignon grapes and in red wines

The aromas found in young Bordeaux red wines made with Merlot and Cabernet Sauvignon suggest a complex mixture of aromas of fresh red fruits such as cherry or blackberry for Merlot, and strawberry or blackcurrant for Cabernet Sauvignon. The aromas of these wines are closely linked with the maturity of the grapes. The climate change that has occurred during the last decade in Bordeaux has induced changes in the ripening conditions of grape berries. It is now widely admitted that over-ripening of the berries during hot and dry summers results in the development of characteristic flavors reminiscent of cooked fruits (fig, prune). The presence of these overriding odors found in both musts and young wines affects the quality and subtlety of the wine flavor and may shorten its shelf life.

Effect of mixed Torulaspora delbrueckii-Saccharomyces cerevisiae culture on rose quality wine

Alcoholic fermentation using no Saccharomyces wine is an effective means of modulating wine aroma. This study investigated the impact of coinoculating Torulaspora delbruecki with two Saccharomyces cerevisiae commercial yeast (QA23, Lallemand; Red Fruit, Sepsa-Enartis) on enological quality parameters, volatile composition and sensory analysis. The following assays were performed on Tempranillo variety: Saccharomyces QA23 (CTQA), Saccharomyces Red Fruit (CTRF), coinoculated T. delbrueckii + S.cerevisiae QA23 (CIQA) and coinoculated T. delbrueckii + S.cerevisiae (CIRF).

Grape byproducts as source of resveratrol oligomers for the development of antifungal extracts

Grape canes are a non-recycled byproduct of wine industry (1-5 tons per hectare per year) containing valuable phytochemicals of medicine and agronomical interest. Resveratrol and wine polyphenols are known to exert a plethora of health-promoting effects including antioxidant capacity, cardioprotection, anticancer activity, anti-inflammatory effects, and estrogenic/antiestrogenic properties (Guerrero et al. 2009). Additionally, resveratrol is a major phytoalexin produced by plants in response to various stresses and promotes disease resistance (Chang et al. 2011). Our project aims to develop polyphenol-rich grape cane extracts to fight phytopathogenic or clinically relevant fungi. We initiate the project with the development of analytical methods to analyze resveratrol mono- and oligomers (dimers, trimers and tetramers) from grape canes and we evaluate their potential activity against clinically relevant opportunistic fungal pathogens (Houillé et al. 2014).

Interest and impact of PVP/PVI (Polyvinylpyrrolidone/ Polyvinylimidazole) on winemaking and final quality of wines

Céline Sparrow a, Christophe Morge a, a SOFRALAB SAS, 79, av. A.A. Thévenet – CS 11031 – 51530 Magenta, France Consumers’ health and security force authorities to limit, in wine as in others food industry products, the concentration in « dangerous » molecules. Therefore the legal limit in heavy metals keeps on decreasing. As per proof EU regulation just decrease the stain concentration in wine from 0,2 to 0,15 mg/l. Certain changes , such as sodium arsenite treatment in vines, disappearance of brass in wineries to the benefit of stainless steel, limit even more the concentration of heavy metals in wines. But the use of copper derivates in vines treatments is difficult to replace. In the case of wine and its elaboration, the problem is even more complex. Indeed, regulation forces the wine producers to control the concentration of certain heavy metals in final wines.