OENO IVAS 2019 banner
IVES 9 IVES Conference Series 9 Colloidal stabilization of young red wine by Acacia Senegal gum: the major implication of protein-rich arabinogalactan-proteins

Colloidal stabilization of young red wine by Acacia Senegal gum: the major implication of protein-rich arabinogalactan-proteins

Abstract

Acacia senegal gum (Asen) is an edible dried gummy exudate [1] added in young red wines to ensure their colloidal stability, precluding the precipitation of the coloring matter. Asen macromolecules, belonging to the arabinogalactan-protein (AGP) family [2], are hyperbranched, charged and amphiphilic heteropolysaccharides composed especially of sugars (92-96 %) and a small fraction of proteins (1-3 %). Asen is defined as a continuum of macromolecules that could be separated into three fractions by hydrophobic interaction chromatography (HIC) [3-4]. HIC-F1 (85-94 % of Asen), HIC-F2 (6-18 % of Asen) and HIC-F3 (1-3 % of Asen) are named and classified in that order according to their protein content, and then a growing hydrophobicity. The efficiency of Asen towards the coloring matter instability is evaluated according to an “efficacy test” that consists to determine the Asen quantity required to prevent the flocculation by calcium of a colloidal iron hexacyanoferrate solution (International Oenological Codex).

In this study, we investigated the stability mechanism of Asen and its HIC fractions towards the iron hexacyanoferrate – calcium and polyphenols flocculation in hydro-alcoholic solutions and unstable young red wine. The AGPs prevented the colloidal instability of both iron hexacyanoferrate salts and polyphenols in hydro-alcoholic solutions and young red wine with a good correlation between results obtained on both systems. The iron hexacyanoferrate salts was stabilized by electrostatic binding of Asen with calcium, the driver of the flocculation. Experiments performed with HIC fractions showed that the functional property of Asen was only determined by the presence of the AGP rich in proteins (HIC-F2 and HIC-F3 fractions containing 6.3 and 13.8 % of proteins, respectively). HIC-F1, the major fraction in weight that contained 0.5 % of proteins, was thus devoid of colloidal stability properties. The ability of AGP rich in proteins to colloidally stabilize polyphenols was confirmed in a hydro-alcoholic matrix containing polyphenols and unstable young red wines. Moreover, the richer in proteins is the AGP, the best are their colloidal stabilizing properties. The differences observed in the protective activity between AGPs from the three HIC fractions are relied to their protein content but also to their related rate of glycosylation that modulates the protein accessibility to its environment, then their physicochemical properties.

references:

[1] Williams, P.A.; Phillips, G.O., Gum arabic. pp 155-168, In Handbook of Hydrocolloids, 2000, CRC Press, Boca Raton, FL.
[2] Gaspar, Y.; Johnson, K.L.; McKenna, J.A.; Bacic, A; Schultz, C.J., Plant Mol. Biol., 2001, 47, 161-176.
[3] Renard, D.; Lavenant-Gourgeon, L.; Ralet, M.C. ; Sanchez, C., Biomacromolecules, 2006, 7, 2637-2649.
[4] Randall, R.C.; Phillips, G.O.; Williams, P.A., Food Hydrocolloids, 1989, 3, 65-75.

DOI:

Publication date: June 23, 2020

Issue: OENO IVAS 2019

Type: Article

Authors

Michaël Nigen, Rafael Apolinar-Valiente, Pascale Williams,Thierry Doco, Néréa Iturmendi, Virginie Moine, Isabelle Jaouen, Christian Sanchez

UMR IATE Université Montpellier – Montpellier SupAgro – INRA – CIRAD 2 place Pierre Viala, Bâtiment 31 34060 Montpellier 
UMR SPO Université Montpellier – Montpellier SupAgro – INRA – CIRAD 2 place Pierre Viala, Bâtiment 31 34060 Montpellier 
BioLaffort (Floirac, FRANCE)
Alland & Robert 

Contact the author

Keywords

Colloidal stabilization, Acacia gum, Coloring matter, Young red wine 

Tags

IVES Conference Series | OENO IVAS 2019

Citation

Related articles…

Vineyard management strategies adopted to mitigate the impacts of climate change affect the evolution of phenolics and color during bottle aging of Aglianico wines

In recent years several strategies have been proposed to cope with the effect of climate change on grape berry quality but only a few studies have dealt with the influence of management practices implemented in the field (e.g. irrigation,summer pruning, etc.), on the evolution of wines over time. 

Grapevine responses to red blotch disease – a structural-functional perspective of symptomatology development and fruit quality

Red Blotch disease caused by Grapevine red blotch-associated virus (GRBaV) is a severe concern to grape growers and winemakers in major grape-growing regions worldwide. One key aspect of all viruses, including Red Blotch, is their intimate association with cell components and anomalous structures following infection. Therefore, the objective of this study was to analyze symptomatology, vine function, fruit quality and ultrastructure of various tissues and document the relationship of ultrastructural cytopathology with the GRBaV infection in Pinot Noir and Merlot employing various microscopy techniques.

Influence of the agronomic management on the aroma of Riesling wines

Nitrogen fertilisation of grapevines is known to influence not only plant development and production yield, but also yeast assimilable nitrogen (YAN). This parameter is related to the growth of yeast

From protein-centered to gene-centered approaches to investigate DNA-protein interactions in grapevine

DNA-binding proteins play a pivotal role in critical cellular processes such as DNA replication, transcription, recombination, repair, and other essential activities. Consequently, investigating the interactions between DNA and proteins is of paramount importance to gain insights into these fundamental cellular mechanisms. Several methodologies have been devised to uncover DNA-protein interactions, which can be broadly categorized into two approaches. The “protein-centered” approach focuses on identifying the DNA sequences bound by a specific transcription factor or a set of TFs. Techniques falling within this category include chromatin immunoprecipitation, and protein-binding microarrays.

Effect of redox mediators on the activity of laccase from Botrytis cinerea against volatile phenols

Volatile phenols namely 4-ethylphenol and 4-ethylguaiacol are formed by enzymatic decarboxylation of hydroxycinnamic acids by Brettanomyces yeasts to give vinylphenols and subsequent reduction of the vinyl group to form the correspondent ethylphenols. The presence of these compounds in wine affects negatively its aromatic quality, conferring unpleasant animal and phenolic odor when present in quantities above the olfactory detection threshold [1]. Several methods have been described to remove these undesirable compounds from wines, including the use laccase enzymes [2, 3]. Due to this, the aim of this work was to evaluate the effect of several natural redox mediators on the activity of Botrytis cinerea laccase against these volatile phenols.