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…

Vinos de tea en la isla de la Palma

En el Norte de la Isla de La Palma (Islas Canarias), se cultivan un conjunto de varietales constituidos principalmente por Negramoll, Listán blanco, Prieto, Albillo y Muñeco.

Impact of polyclonal selection for abiotic stress tolerance on the yield and must quality traits of grapevine varieties

The effects of climate change in viticulture are currently a major concern, with heat waves and drought affecting yield, wine quality, and in extreme cases, even plant survival. Ancient grapevine varieties have high intravarietal genetic variability that so far has been explored successfully to improve yield and must quality. Currently, there is little information available on intravarietal variability regarding responses to stress. In the current work, the intravarietal genetic variability of several Portuguese varieties was studied for yield, must quality, and tolerance to abiotic stress, through indirect, rapid, and nondestructive measurements carried out in the field.

What are the optimal ranges and thresholds for berry solar radiation for flavonoid biosynthesis?

In wine grape production, canopy management practices are applied to control the source-sink balance and improve the cluster microclimate to enhance berry composition. The aim of this study was to identify the optimal ranges of berry solar radiation exposure (exposure) for upregulation of flavonoid biosynthesis and thresholds for their degradation, to evaluate how canopy management practices such as leaf removal, shoot thinning, and a combination of both affect the grapevine (Vitis vinifera L. cv. Cabernet Sauvignon) yield components, berry composition, and flavonoid profile under context of climate change. First experiment assessed changes in the grape flavonoid content driven by four degrees of exposure. In the second experiment, individual grape berries subjected to different exposures were collected from two cultivars (Cabernet Sauvignon and Petit Verdot). The third experiment consisted of an experiment with three canopy management treatments (i) LR (removal of 5 to 6 basal leaves), (ii) ST (thinned to 24 shoots per vine), and (iii) LRST (a combination of LR and ST) and an untreated control (UNT). Berry composition, flavonoid content and profiles, and 3-isobutyl 2-methoxypyrazine were monitored during berry ripening. Although increasing canopy porosity through canopy management practices can be helpful for other purposes, this may not be the case of flavonoid compounds when a certain proportion of kaempferol was achieved. Our results revealed different sensitivities to degradation within the flavonoid groups, flavonols being the only monitored group that was upregulated by solar radiation. Within different canopy management practices, the main effects were due to the ST. Under environmental conditions given in this trial, ST and LRST hastened fruit maturity; however, a clear improvement of the flavonoid compounds (i.e., greater anthocyanin) was not observed at harvest. Methoxypyrazine berry content decreased with canopy management practices studied. Although some berry traits were improved (i.e. 2.5° Brix increase in berry total soluble solids) due to canopy management practices (ST), this resulted in a four-fold increase in labor operations cost, two-fold decrease in yield with a 10-fold increase in anthocyanin production cost per hectare that should be assessed together as the climate continues to get hot.

THE INFLUENCE OF COMMERCIAL SACCHAROMYCES CEREVISIAE ON THE POLY-SACCHARIDES AND OTHER CHEMICAL PROFILES OF NEW ZEALAND PINOT NOIR WINES

Wine polysaccharides (PS) play an important role in balancing mouthfeel and stability of wine and even influence aroma volatility. Despite this, there is limited research into the effect of winemaking additives on the polysaccharide profile and other macromolecules of New Zealand (NZ) Pinot noir wine. In this study the influence of a selection of commercial S. cerevisiae strains on the chemical profile, including polysaccharides, of New Zealand Pinot noir (PN) wine was investigated. Research scale PN fermentations using five strains of commercially available S. cerevisiae (Lalvin EC1118 and RC212, Levuline BRG YSEO, Viallate Ferm R71 and R82) were undertaken. PS were qualified and quantified using HPLC-RID.

Challenges and opportunities for increasing organic carbon in vineyard soils: perspectives of extension specialists

Context description and research question: an increasing number of farmers are considering the impact of conservation practices on soil health to guide sustainable management of vineyards. Understanding impacts of soil management on soil organic carbon (SOC) is one lever for adoption of agroecological practice with potential to help maintain or improve soil health while building SOC stocks to mitigate climate change (Amelung et al., 2020).