Macrowine 2021
IVES 9 IVES Conference Series 9 Study of the colour and phenolic evolution of three different tannin/anthocyanin ratios over time in a model wine

Study of the colour and phenolic evolution of three different tannin/anthocyanin ratios over time in a model wine

Abstract

Phenolic compounds are important quality indicators in red wine. A large number of polyphenols play an important role in wine development, contributing to the colour and the sensory perception of the wines. Anthocyanins are the pigments responsible for the colour in young red wines while tannins are the principal contributors to the bitterness and the astringency of the wines. Wine polyphenols are considered more complex molecules than grape phenolics, due to the enormous number of chemical reactions which take place during the entire winemaking process and storage, forming more stable compounds. In theory, the tannin/anthocyanin ratio could affect the development of the phenolic profile of the wine. Oxygen also plays an essential part in wine’s colour and phenolic stabilization. The main aim of the study is to evaluate the colour and phenolic evolution over time of three different tannin/anthocyanin ratios in a model wine system as well as the impact that oxygen has on this. The three different tannin/anthocyanin ratios were selected according to a different volume of seeds: skins (Sk) with no seeds added, skins + seeds (SkS) and skins + 4 times seeds (Sk4S). The extractions took place in model wine solution. The three treatments were separated into two oxygen treatments and stored hermetically closed vials. Preliminary results show, as expected, a similar amount of anthocyanin in all the treatments and higher tannin concentration in the 4 time seeds treatment. Oxygen consumption also seemed to differ between the ratios. The colour and phenolic evolution will be reported at different sampling stages over time.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Poster

Authors

Gonzalo Garrido Bañuelos*, André De Villiers, Astrid Buica, Wessel du Toit

*Stellenbosch University

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

Related articles…

Oligosaccharides in red wines: could their structure and composition be influenced by the grape-growing

Oligosaccharides have only recently been characterized in wine, and the information on composition and content is still limited. In wine, these molecules are mainly natural byproducts of the degradation of grape berry cell wall polysaccharides. Wine oligosaccharides present several physicochemical properties, being one relevant factor linked to the astringency perception of wines (1,2). A terroir can be defined as a grouping of homogeneous environmental units based on the typicality of the products obtained. This notion is particularly associated with wine, being the climate and the soil two of the major elements of terroir concept.

Novel contribution to the study of mouth-feel properties in wines

In general, there is a well-established lexicon related to wine aroma and taste properties; however mouth-feel-related vocabulary usually includes heterogeneous, multimodal and personalized terms. Gawel et al.
(2000) published a wheel related to mouthfeel properties of red wine. However, its use in scientific publications has been limited. The authors accepted that the approach had certain limitations as it included redundant and terms with hedonic tone and some others were absent. It is of high interest to generate a mouth-feel lexicon and finding the chemical compound or group of compounds responsible for such properties in red wine. In the present work a chemical fractionation method has been developed.

Maturation of Agiorgitiko (Vitis vinifera) red wine on its wine lees: Impact on its phenolic composition

Maturation of wine on lees (often referred as sur lie) is a common practice applied by many winemakers around the world. In the past this method was applied mainly on white and/or sparkling wine production but recently also to red wine production. In our experiment, we matured red wine on wine lees of two origins: a) Light wine lees, collected after the completion of the alcoholic fermentation, b) Heavy lees, collected after the completion of the malolactic fermentation. The lees were free of off-odors and were added in the red wine in percentage 3% and 8%, simulating common winemaking addition. The maturation lasted in total six months and samples were collected for analysis after one, three and six months. During storage the lees were stirred.

Molecular cloning and characterization of UDP-glucose: furaneol glucosyltransferase gene from Japanese

2,5-Dimethyl-4-hydroxy-3(2H)-furanone (furaneol) is an important aroma compound in fruits, such as pineapple and strawberry, and is reported to contribute to the strawberry-like note in some wines. Several grapevine species are used in winemaking, and furaneol is one of the characteristic aroma compounds in wines made from American grape (Vitis labrusca) and its hybrid grape, similar to methyl anthranilate. Muscat Bailey A is a hybrid grape variety [V. labrusca (Bailey) x V. vinifera (Muscat Hamburg)], and its wine is one of the most popular in Japan. The inclusion of Muscat Bailey A in the ‘International List of Vine and Varieties and their Synonyms’ managed by the ‘International Organisation of Vine and Wine (OIV)’ in 2013 has further fueled its popularity among winemakers and researchers worldwide.

Evaluation of Polarized Projective Mapping as a possible tool for attributing South African Chenin blanc dry wine styles

Multiple Factor Analysis (MFA) According to the Chenin blanc Association of South Africa, there are three recognized dry wine styles, Fresh and Fruity (FF), Rich and Ripe Unwooded (RRU), and Rich and Ripe Wooded (RRW), classically attributed with the help of sensory evaluation. One of the “rapid methods” has drawn our attention for the purpose of simplifying and making style attribution for large sample sets, evaluated during different sessions, more robust. Polarized Projective Mapping (PPM) is a hybrid of Projective Mapping (PM) and Polarised Sensory Positioning (PSP). It is a reference-based method in which poles
(references) are used for the evaluation of similarities and dissimilarities between samples.