terclim by ICS banner
IVES 9 IVES Conference Series 9 ANTHOCYANINS EXTRACTION FROM GRAPE POMACE USING EUTECTIC SOLVENTS

ANTHOCYANINS EXTRACTION FROM GRAPE POMACE USING EUTECTIC SOLVENTS

Abstract

Grape pomace is one of the main by-products generated after pressing in winemaking.Emerging methods, such as ultrasound-assisted extraction with eutectic mixtures, have great potential due to their low toxicity, and high biodegradability. Choline chloride (ChCl) was used as a hydrogen bond acceptor and its corresponding hydrogen bond donor (malic acid, citric acid, and glycerol: urea). Components were heated at 80 °C and stirred until a clear liquid was obtained. Distilled water was added (30 % v/v). A solid-liquid ratio of 1 g pomace per 10 ml of eutectic solvent was used. Total anthocyanins were determined. Malvidin-3-O-coumaroylglucoside was quantified by HPLC. Metabisulfite bleaching and the viscosity of the extracts were also determined. The highest extraction was obtained for the methanol/water system.The eutectic system that showed the highest extraction was the mixture of choline chloride, urea, and glycerol in a molar ratio of 1:1:1. Glycerol is classified as a polyol. It can modify the polarity of water so it can be used as a co-solvent in the extraction of polyphenols. In addition, it is considered a highly flexible molecule, capable of forming intra- and intermolecular hydrogen bonds [1]. The higher extraction of choline chloride glycerol and urea (molar ratio 1:1:1) could be due to the influence of the lower polarity of glycerol presenting a higher affinity, probably with malvidin-3-O-coumaroylglucoside, which is less polar than Mv-3-O-glc. In HPLC analysis, malvidin-3-O-coumaroylglucoside was the main anthocyanin identified in all extracts.In eutectic mixtures, viscosity is the property that limits the extraction process compared to conventional solvent extractions. The extract obtained with the choline chloride: urea: glycerol (1:2:2) system had the lowest viscosity values, while the rest of the extracts presented higher viscosities. Viscosity reflects how compact a molecular structure is. Therefore, it can be inferred that the systems with malic acid and citric acid with choline chloride in molar ratios 1:2 present a compact molecular structure with a minimum of holes, which results in less diffusion during the extraction process. The choline chloride: malic acid (1:1) system presented significant resistance to sulfite bleaching at pH 3.5, losing approximately 34 % of color. The choline chloride: urea: glycerol (1:1:1) system lost approximately 50 % of the color, presenting a lower resistance to discoloration.

1. A. P. Abbott, R. C. Harris, K. S. Ryder, C. D’Agostino, L. F. Gladden, and M. D. Mantle, “Glycerol eutectics as sustainable solvent systems,” Green Chem., vol. 13, no. 1, pp. 82–90, 2011

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Lilisbet Castellanos-Gallo¹, Lourdes Ballinas-Casarrubias¹, Jose-Carlos Espinoza-Hicks¹,  Johan Mendo-Za-Chacón¹, León Hernandez-Ochoa¹

1. Facultad de Ciencias Químicas, Universidad Autónoma de Chihuahua, Ciudad Universitaria s/n, C.P. 31170 Chihuahua Mexico

Contact the author*

Keywords

Extraction, malvidin-3-O-coumaroylglucoside, Eutectic solvents, Grape pomace

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

Influence of agrophotovoltaic on vine and must in a cool climate

The current energy crisis means that interest in agrophotovoltaics has increased significantly. The reason behind this is that the system aims to combine agricultural production with energy production. During the three-year period from 2020 to 2022, the effects of photovoltaic panels on the vine, the yield and the quality of the must were studied in Walenstadt in northern Switzerland, an area with a cool, humid climate. 65 Pinot noir vines were planted in the 160m2 study area. Because of the large edge effects, only 3 repetitions with 4 vines each could be created. A significantly lower leaf infestation by Plasmopara viticola was observed among the panels in each of the three years.

NEW TOOL FOR SIMULTANEOUS MEASUREMENT OF OXYGEN CONSUMPTION AND COLOUR MODIFICATIONS IN WINES

Measuring the effect of oxygen consumption on the colour of wines as the level of dissolved oxygen decreases over time is very useful to know how much oxygen a wine is able to consume without significantly altering its colour. The changes produced in wine after being exposed to high oxygen concen-trations have been studied by different authors, but in all cases the wine has been analysed once the oxygen consumption process has been completed. This work presents the results obtained with the use of an equipment designed and made to measure simultaneously the level of dissolved oxygen and the spectrum of the wine, during the oxygen consumption process from saturation levels with air to very low levels, which indicate the total consumption of the dosed oxygen.

Overhead spray water treatment as a mitigation strategy for reducing vine stress and preserving grape quality during heatwaves

Changes in climate have been influencing the quality of wine grapes worldwide. The impact of extreme climate events over short periods is increasingly recognized as a serious risk to grape quality and yield quantity. In this study the mitigation effects of a pulsed water spray on vine canopy during heatwave events has been evaluated for maintaining vine condition during the growing season and grape quality. Vines of three varieties (Malbec, Bonarda, and Syrah) under drip irrigation in the UNCuyo experimental vineyard were treated with an overhead pulsed water spray.

UNEXPECTED PRODUCTION OF DMS POTENTIAL DURING ALCOOLIC FERMENTATION FROM MODEL CHAMPAGNE-LIKE MUSTS

The overall quality of aged wines is in part due to the development of complex aromas over a long period (1.) The apparition of this aromatic complexity depends on multiple chemical reactions that include the liberation of odorous compounds from non-odorous precursors. One example of this phenomenon is found in dimethyl sulphide (DMS) which, with its characteristic odor truffle, is a known contributor to the bouquet of premium aged wine bouquet (1). DMS supposedly accumulates during the ten first years of ageing thanks to the hydrolysis of its precursor dimethylsulfoniopropionate (DMSp.) DMSp is a possible secondary by-product from the degradation of S-methylmethionine (SMM), an amino acid iden- tified in grapes (2), which can be metabolized by yeast during alcoholic fermentation.

PROFILING OF LIPIDS IN WINES FROM MONOCULTURE FERMENTATION WITH INDIGENOUS METSCHNIKOWIA YEAST SPECIES

Lipids are a diverse group of organic compounds essential for living systems. They are vital compounds for yeast which makes them an important modulator of yeast metabolism in alcoholic fermentation. This study presents a comprehensive lipidome analysis of wine samples from the Vitis vinifera L., Maraština. The fermentation trails were set up in monoculture with different indigenous yeast strains selected from a collection of native yeasts established at the Institute for Adriatic Crops and Karst Reclamation in 2021, previously isolated from Croatian Maraština grapes: Metschnikowia pulcherrima, Metshnikowia sinensis/shanxiensis , and Metschnikowia chyrsoperlae.