 IVES 9 IVES Conference Series 9 Chemical and colorimetric study of copigmentation between malvidin-3-O-glucoside and wine polyphenols and polysaccharides

Chemical and colorimetric study of copigmentation between malvidin-3-O-glucoside and wine polyphenols and polysaccharides

Abstract

AIM: The objective of this work was to perform a colorimetric study of the copigmentation between malvidin-3-O-glucoside, one of the main anthocyanins in red wines, and different wine phenolic compounds and polysaccharides. The present work also aimed to study the stabilization effect on the flavylium cation due to the copigmentation interactions with these compounds.

METHODS: Copigmentation was studied in model systems containing malvidin-3-O-glucoside and different copigments, including flavonols, flavanols, hydroxycinnamic and hydroxybenzoic acids and also polysaccharides at two pH values. The stability of the flavylium cation (25 ºC for 5 weeks) was assessed by HPLC-DAD in an acid medium whereas the study of copigmentation and its relevance on color was carried out at wine like pH (pH 3.6) by differential colorimetry using CIELAB parameters calculated from the whole visible spectra.

RESULTS: Important changes in the CIELAB parameters of the model systems were observed depending on the phenolic compound assayed as copigment, which could point out differences on the copigmentation interactions established. In the case of polysaccharides, it has been observed that they could play a role on the copigmentation effect. Moreover, copigmentation reactions seem to exert an influence on the flavylium cation stability by stabilizating the flavylium concentration during the length of the study or favoring the formation of anthocyanin-derived pigments.

CONCLUSIONS

Color changes and stability of the flavylium cation due to copigmentation phenomenon between anthocyanin and phenolic compounds and/or polysaccharides can be related to the copigment structure.

DOI:

Publication date: September 13, 2021

Issue: Macrowine 2021

Type: Article

Authors

Bárbara Torres-Rochera

Department of Analytical Chemistry, Nutrition and Food Sciences, Universidad de Salamanca, Salamanca, E37007, Spain. ,Ignacio GARCÍA-ESTÉVEZ, Department of Analytical Chemistry, Nutrition and Food Sciences, Universidad de Salamanca, Salamanca, E37007, Spain. María Teresa ESCRIBANO-BAILÓN, Department of Analytical Chemistry, Nutrition and Food Sciences, Universidad de Salamanca, Salamanca, E37007, Spain.

Contact the author

Keywords

anthocyanins, phenolic compounds, polysaccharides, copigmentation, wine stability

Citation

Plant fibers in comparison with other fining agents for the re-duction of pesticide residues and the effect on the volitile profile of Austrian white and red wines.

Pesticide residues in Austrian wines have so far been poorly documented. In 250 wines, 33 grape musts and 45 musts in fermentation, no limit values were exceeded, but in some cases high lev-els (>0.100 mg/l) of single residues were found, meaning that a reduction of these levels before bottling could make sense. In the course of this study, a white and a red wine were spiked with a mix of 23 pesticide residues from the group of fungicides (including botryticides), herbicides and insecticides. The influence of the following treatments on residue concentrations and volatile profiles were investigated: two activated charcoal products, a bentonite clay, two commer-cial mixed fining agents made of bentonite and charcoal, two yeast cell wall products, and a plant fiber-based novel filter additive. The results of this study show that all the agents tested reduced both residues and aromavolatile compounds in wine, with activated charcoal having the strongest effect and bentonite the weakest. The mixed agents and yeast wall products showed less aroma losses than charcoal products, but also lower residue reduction. Plant fibers showed good reduction of pesticides with moderate aroma damage, but these results need to be con-firmed under practical conditions.

Unravelling the microbial community structure and aroma profile of Agiorgitiko wine under different inoculation schemes

Agiorgitiko (Vitis vinifera L. cv.) is the most widely cultivated indigenous red grape variety in Greece, known for the production of Protected Designation of Origin Nemea wines.

Oxygen transfer through cork stoppers

During wine conservation in a bottle, the control of oxygen transfer from the outside environment to the wine inside the bottle is a key parameter that determines the wine quality. Many other factors can also influence the evolution of wine during postbottling aging,

Raman spectroscopy as a rapid method to assess grape polyphenolic maturation and wine malolactic fermentation on site

Wineries can increase their economic and environmental sustainability by optimizing the winemaking procedures, from harvest to wine maturation and conservation. Based on analytical data of the chemical composition and wine sensory evaluation, the enologist makes his own decision regarding the enological interventions at the harvest date selection, winemaking and post-winemaking.

Polyphenolic profile and dietary fiber content of skins and seeds from unfermented and fermented grape pomace

The valorization of winemaking byproducts is subordinated to the knowledge of their chemical characteristics. This work concerned the determination of the polyphenolic profile and the dietary fiber content of skins and seeds from unfermented and fermented pomace of different cultivars (Moscato bianco, Cortese, Arneis, Pinot Noir, Barbera, Grignolino, Nebbiolo), sampled from some wineries in the Piedmont area (Italy) during the 2020 harvest.