IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Study of the Interactions between High Molecular Weight Salivary Proteins and Red Wine Flavanols.

Study of the Interactions between High Molecular Weight Salivary Proteins and Red Wine Flavanols.

Abstract

Astringency has been defined by the American Society for Testing Materials as “the complex of sensations due to shrinking, drawing or puckering of the epithelium as a result of exposure to substances such as alums or tannins”. Regarding the importance of astringency in wine consumer acceptance, elucidating the molecular mechanisms underpinning this complex sensation represents an important goal for scientists. Although different mechanisms have been described (Gibbins & Carpenter, 2013), the salivary protein precipitation is still the most accepted theory. According to this, wine astringency perceived in the oral cavity is originally attributed to the interaction and subsequence precipitation of salivary proteins by wine tannins –mainly flavanols–.

Human saliva is rich in different types of peptides and proteins: histatins, statherin, P−B peptide, cystatins and proline-rich proteins (PRPs), being the latter ones the most studied regarding the development of astringency (Ramos-Pineda et al., 2019; Soares et al., 2018). However, other high molecular weight (HMW) proteins like albumin, α-amylase and mucins are the major components of the human salivary proteome (Cheaib & Lussi, 2013; Castagnola et al., 2011) and little research has been reported in relation to their implication in the astringency development. Here, the molecular interactions between the HMW salivary proteins, namely, albumin from human serum, α-amylase from human saliva (Type XIII-A) and mucin from bovine submaxillary glands (Type I-S), and a seed flavanol extract with a composition similar to that found in red wine have been characterized by Fluorescence Quenching and Isothermal Titration Calorimetry (ITC). Moreover, in order to obtain further insights into the specific flavanols that are involved in the interactions with HMW salivary proteins, each binding assay has been analysed by HPLC–MS. The obtained results suggested that HMW salivary proteins could be implicated in the astringency development, since these proteins were able to interact and to precipitate wine flavanols, although with different involvement depending on the HWM protein assayed since a clear ligand preference was observed.

References

Castagnola et al., 2011. Trends in Biotech., 29(8), 409–418.
Cheaib & Lussi, 2013. J. Biosci., 38(2), 259–265.
Gibbins & Carpenter, 2013. J. Texture Stud., 44(5), 364−375.
Ramos-Pineda et al., 2019. Food Chem., 272, 210−215.
Soares et al., 2018. Food Chem., 243, 175−185.

DOI:

Publication date: June 27, 2022

Issue: IVAS 2022

Type: Poster

Authors

Manjón Elvira1, García-Estévez Ignacio1 and Escribano-Bailón Mará Teresa1

1Department of Analytical Chemistry, Nutrition and Food Science, Universidad de Salamanca.

Contact the author

Keywords

mucin, albumin, amylase, molecular interactions, ITC

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

The key role of vineyard parcel in modifying flavor compounds of Cabernet Sauvignon grapes

To produce premium wines in a specific region is the goal of local oenologists. This study aimed to investigate the influence of soil properties on the flavoromics of Cabernet Sauvignon grapes to provide a better insight into single-vineyard wines. Six commercial Cabernet Sauvignon vineyards were selected in the Manas region to collect berries at three harvest ripeness in three seasons (2019–2021). The six vineyards had little difference in mesoclimate conditions while varying greatly in soil composition.

A new winemaking technology: fermentation, aging and bottling without added additives and preservatives

Auric infinity Technology introduces three new patented products designated for fermentation, aging and bottling without added additives and preservatives that have never been used in the winemaking industry.

Effect of riboflavin on the longevity of white and rosé wines

Light is a fundamental part at sales points which influences in the conservation of wines, particularly in those that are sold in transparent glass bottles such as rosé wines and increasingly white wines. The photochemical effect known as “light-struck taste” can cause changes in the aromatic characteristics of the wine. This “light-struck taste” is due to reactions triggered by the photochemical sensitivity of riboflavin (RBF).

Postveraison shoot trimming in Tannat and Merlot: preliminary results on yield components, plant balance and berry composition

There is currently a trend towards the production of wines with low alcohol content. To achieve this, grapes with low sugar content must be used. There are techniques at the vineyard level that can delay ripening and avoid excessive sugar accumulation without, a priori, affecting the final polyphenol content. Postveraison shoot trimming (PVST) is experimentally evaluated for these purposes, but its impact under Uruguayan climatic conditions with high interannual variability is not known. The aim of this work is to assess the PVST in Tannat and Merlot cultivars and their impact on yield components, plant balance and berry primary composition. In this study, two commercial vineyards of 10 years old Tannat and Merlot (grafted on SO4) at Canelones Department were selected. During the 2020-201 growing season, grapevines were submitted to PVST when grapes reached 15º Brix. In a randomized block, trimmed (T) and control (C) plants were evaluated with three repetitions each cultivar. Evaluation of the evolution of primary berry composition during ripening, measurement of yield components and plant balance were performed. For both cultivars, PVST did not affect yield components. Merlot reached 5.4 kg per plant and Tannat 7.1 kg, with not statistical significance between treatments. However, statistical differences were observed in terms of plant balance. In Merlot Ravaz Index reached a difference of 5.3 (12.0 in T and 6.7 in C) meanwhile Tannat reached 3.5 of statistical difference (13.7 in T and 10.2 in C). The tendency to imbalance for the treated plants had an impact on the final grape composition. Merlot grapes showed statistical difference in final total acidity (0.3 g of difference between treatments) while treatments impact final sugar content on Tannat grapes (10.0 g of difference between treatments). Further studies are needed to assess the impact of different canopy management techniques in our conditions.

Nitrogen partitioning among vine organs as a consequence of cluster thinning

Agroscope is investigating the impact of yield on nitrogen (N) partitioning in grapevine and on must composition. The mechanism of N assimilation