terclim by ICS banner
IVES 9 IVES Conference Series 9 EXPLORING THE INFLUENCE OF S. CEREVISIAE MANNOPROTEINS ON WINE ASTRINGENCY AND THE IMPACT OF THEIR POLYSACCHARIDE STRUCTURE

EXPLORING THE INFLUENCE OF S. CEREVISIAE MANNOPROTEINS ON WINE ASTRINGENCY AND THE IMPACT OF THEIR POLYSACCHARIDE STRUCTURE

Abstract

Mannoproteins (MPs) are proteoglycans from the outmost layer of yeast cell walls released into wine during alcoholic fermentation and ageing on lees processes. The use of commercial preparations of mannoproteins as additives to improve wine stability with regards to the crystallization of tartaric salts and to prevent protein haze in the case of white and rosé wines is authorized by the OIV.

Regarding red wines and polyphenols, mannoproteins are described as able to improve their colloidal stability and modulate the astringent effect of condensed tannins. The latter interact with salivary proteins forming insoluble aggregates that cause a loss of lubrication in the mouth and promote a drying and puckering sensation. However, neither the interaction mechanisms involved in mannoproteins capacity to impact astringency nor the structure-function relationships related to this property are fully understood.

The aim of this study was to evaluate the impact of high molecular weight mannoproteins on tannin-protein interactions. To this end, experiments were performed in a model wine using tannins purified from a red Syrah wine and BSA. Tannin-BSA aggregation kinetics were followed for 1 hour through Dynamic Light Scattering measurements in the absence and presence of mannoproteins. To progress in the identification of structure-function relationships and on the part played by the polysaccharide part, mannoproteins fractions from four yeast strains were extracted and purified. Yeast Strains were selected according to their origin and specific mannoprotein polysaccharide structure: a commercial enological strain (MP-LMD47), the wild-type BY4742 strain (MP-WT), and two of its mutants ΔMnn4 (MP-Mnn4, no mannosyl-phosphorylation) and ΔMnn2 (MP-Mnn2, linear N-glycosylation backbone). A thorough characterization of mannoprotein fractions confirmed the structural differences between mannoproteins from each yeast strain.

MPs were capable of delaying tannin-BSA aggregation kinetics by preventing the formation of micron-sized particles within the hour of measurement but did not avoid the long-term precipitation of tannin-BSA aggregates. Experiments indicated that mannoproteins interfere with tannin-BSA enlarged aggregation through the formation of a ternary MP-Tannin-BSA system. To be able to prevent tannin-BSA particle growth, the density/compactness of the polysaccharide moiety of MPs was a key factor.

 

1. Boulet, J.-C., Trarieux, C., Souquet, J.-M., Ducasse, M.-A., Caillé, S., Samson, A., … Cheynier, V. (2016). Models based on ultraviolet spectroscopy, polyphenols, oligosaccharides and polysaccharides for prediction of wine astringency. Food Chemistry, 190, 357–363. https://doi.org/10.1016/j.foodchem.2015.05.062
2. Cheynier, V. (2012). Phenolic compounds: from plants to foods. Phytochemistry Reviews, 11(2–3), 153–177. https://doi. org/10.1007/s11101-012-9242-8
3. Soares, S., Mateus, N., & de Freitas, V. (2012). Carbohydrates Inhibit Salivary Proteins Precipitation by Condensed Tannins. Journal of Agricultural and Food Chemistry, 60(15), 3966–3972. https://doi.org/10.1021/jf3002747
4. Vidal, S., Francis, L., Guyot, S., Marnet, N., Kwiatkowski, M., Gawel, R., … Waters, E. J. (2003). The mouth-feel properties of grape and apple proanthocyanidins in a wine-like medium. Journal of the Science of Food and Agriculture, 83(6), 564–573. https://doi.org/10.1002/jsfa.1394

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Article

Authors

Saul Assunção Bicca1,2, Céline Poncet-Legrand¹, Stéphanie Roi¹, Julie Mekoue², Thierry Doco¹ And Aude Vernhet¹

1. SPO Institut Agro, INRAE, Univ Montpellier, Montpellier, France.
2. Lallemand, SAS, 19 rue des Briquetiers, BP 59, 31702 Blagnac, France

Contact the author*

Keywords

Mannoproteins, Physico-chemical Interactions, Astringency, Condensed Tannins

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

INFLUENCE OF WINEMAKING VARIABLES AND VINEYARD LOCATIONS ON CHEMICAL AND SENSORY PROFILES OF SOUTH TYROLEAN PINOT BLANC

Pinot Blanc, an important grape variety grown in some mountain areas of Northern Italy such as South Tyrol over the last decades, with its cultivation covering 10.3% of the total vineyards, has compatible climatic conditions (e.g. heat requirements) which are normally found in the geographical areas of the mountain viticulture [1,2,3,4]. Climatic changes are hastening the growth of this variety at higher elevations, particularly for the production of high quality wine.

SENSORY CHARACTERIZATION OF COGNAC EAUX-DE-VIE AGED IN BARRELS REPRESENTING DIFFERENT TOASTING PROCESS

Cognac is an outstanding french wine spirit appreciated around the world and produced exclusively in the Nouvelle-Aquitaine region, and more precisely in the Cognac area. According to AOC regulations (Appellation D’origine Controlée), the spirit required at least 2 years of continuous ageing in oak barrels to be granted the title of Cognac. The oak wood will import color, structure and organoleptic complexity. The different steps during barrel-making process, such as seasoning and toasting, influence the above quality attributes in both wines and spirits.

ANALYZING THE ROLE OF ELEMENTAL SULFUR IN GRAPE JUICE ON THE DEVELOPMENT OF POLYFUNCTIONAL MERCAPTANS IN SAUVIGNON BLANC WINES

Sauvignon blanc is characterized by distinctive aromas, both fruity and herbaceous. The “green” character has been attributed to the methoxypyrazines, while the “fruity” character is associated with polyfunctional mercaptans . Polyfunctional mercaptans are of great significance due to their high impact on wines and associated low perception thresholds.
Elemental sulfur (S⁰) is widely used to protect grapevines from powdery mildew.

UNTARGETED METABOLOMICS ANALYSES TO IDENTIFY A NEW SWEET COMPOUND RELEASED DURING POST-FERMENTATION MACERATION OF WINE

The gustatory balance of dry wines is centered on three flavors, sourness, bitterness and sweetness. Even if certain compounds were already identified as contributing to sweetness, some taste modifications remain largely unexplained1,2. Some empirical observations combined with sensory analyzes have shown that an increase of wine sweetness occurs during post-fermentation maceration³. This step is a key stage of red winemaking during which the juice is left in contact with the marc, that contains the solid parts of the grape (seeds, skins and sometimes stems). This work aimed to identify a new taste-active compound that contributes to this gain of sweetness.

IMPACT OF CLIMATIC ZONES ON THE AROMATIC PROFILE OF CORVINA WINES IN THE VALPOLICELLA REGION

In Italy, in the past two decades, the rate of temperature increases (0.0369 °C per year) was slightly higher compared to the world average (0.0313 °C per year). It has also been indicated that the number and intensity of heat waves have increased considerably in the last decades. (IEA, 2022). Viticultural zones can be classified with climatic indexes. Huglin’s index (HI) considers the temperature in a definite area and has been considered as reliable to evaluate the thermal suitability for winegrape production (Zhang et al., 2023).