IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 The interaction between wine polyphenolic classes and poly-L-proline is impacted by oxygen

The interaction between wine polyphenolic classes and poly-L-proline is impacted by oxygen

Abstract

Oxygen plays a key role in the evolution of wine chemistry, within the non-volatile matrix. Polyphenol composition and structure, as well as the process of tannin polymerisation are directly impacted by oxidation, and this can occur during both fermentation and ageing. Polyphenols play an important role in red wine and exhibit a wide diversity in their structure and properties. They are responsible for wine colour, texture and taste (astringency, bitterness) and exhibit some health properties. The principal class of non-flavonoid polyphenolic compounds are the phenolic acids and stilbenes. Among the flavonoids, anthocyanins and tannins are the major structural classes. The aim of this study was to characterise the detailed response of wine polyphenolic structure and composition to an oxygen treatment applied during fermentation. A specific focus was to determine the interaction of discrete polyphenolic classes with poly-L-proline (PLP). A control Shiraz wine was prepared under reductive conditions during fermentation, in triplicate. To the same grape source, an aeration treatment was initiated on day 3 following a 1.8 °Bé decrease for 48 h at 5 L/min, also in triplicate.  After a 12-month ageing period, wines were fractionated where: F1 = Phenolic acids, F2 = flavan-3-ol monomers, F3 = flavan-3-ol oligomers, F4 = anthocyanins, pyranoanthocyanins; and F5 = polymeric proanthocyanidins, pigmented proanthocyanins and other derived complexes. The composition of fractions F1 to F4 was verified by LC-MS, and F5 was characterised by a combination of analytical techniques specific to proanthocyanidins. The interaction between the polyphenol fractions and PLP was measured by isothermal titration calorimetry (ITC). A strong binding interaction was observed between F1, the phenolic acids, and PLP by ITC, and was not affected by the oxygen treatment. In fact, a strong hydrophobic interaction and hydrogen bonding was implicated in the interaction. It was found that for fractions F2 and F3, no binding events with PLP were observed by ITC, irrespective of the oxygen level applied. Stronger binding events with PLP were observed for the F4 and F5 polyphenolic fractions, but interestingly, only in those prepared from wines which had oxygen treatment. Moreover, hydrophobic interaction and hydrogen bonding was detected just for the oxygen treatment for F4 and F5. Contrary to expectation, no binding with PLP could be detected for F4 and F5 from the control wine. Further investigation of the properties of the fractions was conducted to account for the differences observed, including their composition, hydrophobicity and aggregation. This presentation will provide new insights into the potential role of discrete polyphenolic classes in driving in-mouth sensory properties, like astringency, which might be elicited following binding with proline-rich salivary proteins.

DOI:

Publication date: June 23, 2022

Issue: IVAS 2022

Type: Article

Authors

Jouin Alicia1, Falconer Robert J.2, Waterlot Aude3, Day Martin1, Schmidt Simon1 and Bindon Keren1

1The Australian Wine Research Institute, PO Box 197, Glen Osmond, South Australia, 5064, Australia 
2Department of Chemical Engineering and Advanced Materials, University of Adelaide, Adelaide, SA, 5005, Australia
3Department of Food Science and Human Nutrition, Courtesy Faculty, Horticulture, Iowa State University, 2567 Food Sciences Building, 536 Farm House Lane, Ames, IA 50011, USA

Contact the author

Keywords

Tannins, Anthocyanins, Oxygen, Isothermal Titration Calorimetry, Astringency

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Phenology, thermal requirements and maturation of the SR 0.501-17 wine grape hybrid cultivated in contrasting climate

The use of hybrids in viticulture is one of the alternatives for sustainable production in hot and rainy regions during grapevine maturation. This sustainable production concerns the reduction of pesticide use, adaptation to climate and control of vine decline. The SR 0.501-17 wine grape hybrid, developed in the grapevine program of the Agronomic Institute of Campinas (IAC), is characterized by producing white grapes with small spherical berries with seeds. The agronomic characterization of this hybrid, especially in different climatic conditions, as well as the evaluation of its performance in winemaking are necessary. The objective of this work was to characterize the duration and thermal requirements of the different phenological stages and the influence of rainfall on the physicochemical characteristics of the must in two contrasting climate regions of the State of São Paulo.

Read More

“Vinhos de mesa” et oenophilie : quand les caractéristiques organoleptiques des cépages américains empêchent l’intégration des consommateurs à l’univers de l’appréciation esthétique

Au Brésil, 80 % du vignoble national et 90 % du vignoble de l’État du Rio Grande do Sul (principale région productrice de vins dans le pays) sont plantés avec des cépages issus de vitis labrusca ou de cépages hybrides (DEBASTIANI, 2015). Une partie de cette production est utilisée pour la préparation de jus de raisin et de concentrés de moût ou de pulpe de raisin. Le restant est consacré à

Read More

Local ancient grapevine cultivars to face future viticulture

Among the different strategies to cope with the negative impacts of climate change on viticulture, the exploitation of genetic diversity is one of the most promising to adapt to new conditions and maintain wine production and quality. One of the biggest concerns in the context of climate change is to improve water use efficiency (WUE). In this way, the use of genotypes that present a better response to drought and high WUE is a key issue. In this work, physiological performance analysis was conducted to compare the water deficit stress (WDS) responses of local and widespread grapevines cultivars. Leaf gas exchange, water use efficiency (WUE) at different levels (leaf and long-term WUE (∆13C)), leaf osmotic adjustment and other water relations parameters were determined in plants under well-watered and WDS conditions alongside assessment of the levels of foliar hormones concentrations. Results denote that local cultivars displayed better physiological performance under WDS as compared to the widely-distributed ones. he results corroborate the hypothesis that better stomatal control allows increasing leaf WUE under drought as occurred in the local Callet cv.; but the minority local cultivar Escursac cv. showed high WUE under both treatments. In this case, high WUE can be related to maintaining higher photosynthetic activity under drought. The different mechanisms underlying the better performance under WDS and high WUE of minority local cultivars are discussed.

Read More

Understanding wine as a sensory, emotional, and cognitive experience to promote and communicate conscious consumption

In the complex scenario that the wine industry and its promotion are currently facing, this research proposes a theoretical expansion of the traditional model used to understand the wine experience, namely the classic sensory, emotional and cognitive triad, moving toward a multidimensional approach that also incorporates cultural, symbolic and contextual dimensions in order to comprehend the conscious experience.

Read More

Oenotannins addition in wine: can be the modulation of redox potential predictable?

The purpose of this research was to study the interaction between oenotannins and wine matrix in order to design a targeted oenotannins addition for modulating the redox status of wine. It is in fact known that oenotannins can regulate the redox potential of musts and wines since they are electroactive substances (1).

Read More