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


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


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

*Stellenbosch University

Contact the author


IVES Conference Series | Macrowine | Macrowine 2016


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