Macrowine 2021
IVES 9 IVES Conference Series 9 Dissecting the polysaccharide‐rich grape cell wall matrix during the red winemaking process, using high‐throughput and fractionation methods

Dissecting the polysaccharide‐rich grape cell wall matrix during the red winemaking process, using high‐throughput and fractionation methods

Abstract

Limited information is available on grape wall-derived polymeric structure/composition and how this changes during fermentation. Commercial winemaking operations use enzymes that target the polysaccharide-rich polymers of the cell walls of grape tissues to clarify musts and extract pigments during the fermentations. In this study we have assessed changes in polysaccharide composition/ turnover throughout the winemaking process by applying recently developed cell wall profiling approaches to both wine and pomace polysaccharides. The methods included gas chromatography for monosaccharide composition (GC-MS), infra-red (IR) spectroscopy and comprehensive microarray polymer profiling (CoMPP) using cell wall probes. CoMPP performed on the concentrated soluble wine polysaccharides showed a fraction rich in rhamnogalacturonan I (RGI), homogalacturonan (HG) and Arabinogalactan proteins (AGPs). We also used chemical and enzymatic fractionation techniques in addition to CoMPP to understand the berry deconstruction process more in-depth. CoMPP and gravimetric analysis of the fractionated samples showed that thefermentation-derived pomace could be divided into a pectin-rich fraction (pulp tightly-bound to skins) containing HG, RGI and AGPs; and secondly, a xyloglucan-rich fraction (mainly skins). Interestingly this fraction was found to include pectins consisting of tightly-associated and highly methyl-esterified HG and RGI networks. A unique aspect is datasets suggesting that enzyme-resistant pectin polymers ‘coat’ the inner xyloglucan-rich skin cells. This data has important implications for developing effective strategies for efficient release of favourable compounds (pigments, tannins, aromatics, etc.) from the berry tissues during winemaking. This study provides a framework to understand the complex interactions between the grape matrix and carbohydrate-active enzymes to produce wine of desired quality and consistency.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Article

Authors

John Paul Moore*, Jonatan Fangel, Melane Vivier, William Willats, Yu Gao

*Stellenbosch University

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

Related articles…

Moscatel vine-shoot extracts as grapevine biostimulant to increase the varietal aroma of Airén wines

There is a growing interest in the exploitation of vine-shoots waste, since they are often left or burned. Sánchez-Gómez et al. [1] have shown that vines-shoots aqueous extracts have significant contents of bioactive compounds, among which several polyphenols and volatiles are highlighted. Recent studied had demonstrated that the chemical composition of vine-shoots is enhanced when vine-shoots are toasted
[2,3]. The application of vegetable products in the vineyards has led to significant changes towards a more “Sustainable Viticulture”. An innovative foliar application for Airén vine-shoot extracts have been carried out to the vineyard. It has been shown that they act as grape biostimulants, improving certain wine quality characteristics [4].

Foam characteristics of white, rosé and red sparkling wines elaborated by the champenoise method

Contribution Foam is the characteristic that differentiates sparkling wines from still wines, being the first sensory attribute that tasters and consumers perceive and that determines the final quality of sparkling wines [1]. The foaming properties mainly depend on the chemical composition of wines [2-3], and different factors involved in wine composition will have an effect on foam quality. In Spain, the sparkling wine market focuses on the production of white and rosé sparkling wine, with very low production of red sparkling wines. However, this type of wines is elaborated in countries like Australia, South-Africa, Argentina, Italy or Portugal, with a great acceptance by consumers. No studies on the foaming characteristics of red sparkling wines have been found.

Influence of preflowering basal leaf removal on aromatic composition of cv. Tempranillo wine from semiarid climate (Extremadura Western Spain)

Abstract In this work the effects of early leaf removal performed manually at preflowering phenological stage, on the volatile composition of Tempranillo (Vitis vinifera L.) wines were studied. From 2009-2011 vintages 34 wine volatile compounds were identified and quantified by gas chromatography-mass spectrometry (GC-MS) where early leaf removal only modified 25 of them. The total C6 compounds, acetates and volatiles acids (with exception of isobutyric acid) were affected by defoliation, whereas alcohols and esters showed a minor effect. Furthermore the vintage effect also was shown.

Multivariate strategies for red wines classification using stilbenes and flavonols content

Bioactive polyphenols from grapes and wines, like stilbenes and flavonols (SaF), are often determined to nutritional evaluation, but also for many other purposes. The objective of this study was to quantify SaF in red wines from “Campanha Gaúcha”, a large and young viticultural region from South Brazil. Moreover, through statistical analysis, evaluate the influence of these compounds according to varieties, production process, harvest years and micro-regions of cultivation. A total of 58 samples of red wines were analyzed by high-performance liquid chromatography coupled to diode array detector (HPLC-DAD) for determination of trans-resveratrol (R), quercetin (Q), myricetin (M), kaempferol (K), trans-e-viniferin (V) and their precursor, cinnamic acid (C).

Effect of concentration and competition between different fungicide residues on the adsorption efficiency of activated vegetal fibres for treatment of wine

Vineyards are strongly exposed to fungal diseases, attacks from insects and competition with weeds. Most treatments used on grape vines contain synthetic active substances, which may be transferred to the wine. Such pesticides have a negative image because many active substances are potential health hazards. A specific oenological treatment allowing the reduction of pesticide residues in wine based on activated vegetable fibres (AVF) is under examination by the International Organisation for Vine and Wine. This technique works efficiently and alters the wine only little (Lempereur et al. 2014).