IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 NADES extraction of anthocyanins derivatives from grape pomace

NADES extraction of anthocyanins derivatives from grape pomace

Abstract

Grape pomace is one of the main by-products generated after pressing in wine-making. It’s valorization through the extraction of bioactive compounds is the answer for the development of sustainable processes. Nevertheless, in the recovery of anthocyanins derivatives, the extraction stage continues to be a limiting step. The nature of the sample and the type of solvent determine the efficiency of the process. Anthocyanins are responsible for the color of grapes and wine, a characteristic that is defined by their chemical structure. The color stability in their native form is affected by factors such as pH, temperature, and their chemical structure, which could limit their use as a natural colorant in the food industry. However, there are anthocyanin-derived pigments found in wines. The main interest in these pigments is that they present greater color stability against pH changes and SO2 bleaching than native anthocyanin. Emerging methods such as ultrasound-assisted eutectic mixture extraction have a high potential due to the low toxicity, chemical inertness with water, easy preparation, and huge biodegradability. There are four types of eutectic solvents, however, the mixtures that are formed from salt and a natural component such as alcohols, sugars, and organic acids are the most used in the extraction processes of bioactive compounds. The compounds were mixed with a 1:1 molar ratio with choline chloride (ChCl) as hydrogen bond acceptor (HBA) and its corresponding hydrogen bond donor (HBD) (malic acid, citric acid, tartaric acid, glucose and glycerol: urea), heated at a constant temperature of 80 °C and stirring at 700 rpm until a transparent liquid was obtained. Then the volume of distilled water corresponding to each mixture (30 % v / v) was added. The extraction was carried out in an ultrasonic bath at room temperature for 45 min. A solid-liquid ratio of 1 g of pomace per 10 ml of solvent was used. Total anthocyanins were determined using the differential pH method measured by a spectrophotometer. The highest extraction using NADES corresponds to the mixtures composed of choline chloride: glucose and choline chloride: urea: glycerol reaching a value of 4.57 and 4.36 mg eq of malvidin-3-O-glucoside /g of grape pomace respectively. On the other hand, no significant differences were found for a value of p≤0.05 between the mixtures containing citric acid and tartaric acid, obtaining values of 0.81 and 0.69 mg eq of malvidin -3-O-glucoside /g grape pomace respectively. Although it is known that anthocyanins are more stable in acidic media, the extraction values obtained for mixtures with acids were lower than expected

DOI:

Publication date: June 23, 2022

Issue: IVAS 2022

Type: Article

Authors

Salas Erika¹, Castellanos-Gallo Lilisbet¹, Ballinas-Casarrubias Lourdes1, Espinoza-Hicks José Carlos¹and Hernández-Ochoa León¹

¹Facultad de Ciencias Químicas, Universidad Autónoma de Chihuahua

Contact the author

Keywords

grape pomace, extraction, anthocyanins derivatives, natural deep eutectic solvent (NADES)

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

How does aromatic composition of red wines, resulting from varieties adapted to climate change, modulate fruity aroma?

One of the major issues for the wine sector is the impact of climate change linked to the increasing temperatures which affects physicochemical parameters of the grape varieties planted in Bordeaux vineyard and consequently, the quality of wine. In some varietals, the attenuation of their fresh fruity character is accompanied by the accentuation of dried-fruit notes [1]. As a new adaptive strategy on climate change, some winegrowers have initiated changes in the Bordeaux blend of vine varieties [2]. This study intends to explore the fruitiness in wines produced from grape varieties adapted to the future climate of Bordeaux. 10 commercial single–varietal wines from 2018 vintage made from the main grape varieties in the Bordeaux region (Cabernet franc, Cabernet-Sauvignon and Merlot) as well as from indigenous grape varieties from the Mediterranean basin, such as Cyprus (Yiannoudin), France (Syrah), Greece (Agiorgitiko and Xinomavro), Portugal (Touriga Nacional) and Spain (Garnacha and Tempranillo), were selected among 19 samples using sensory descriptive analyses. Both sensory and instrumental analyses were coupled, to investigate their fruity aroma expression. For sensory analysis, samples were prepared from wine, using a semi preparative HPLC method which preserves wine aroma and isolates fruity characteristics in 25 specific fractions [3,4]. Fractions of interest with intense fruity aromas were sensorially selected for each wine by a trained panel and mixed with ethanol and microfiltered water to obtain fruity aromatic reconstitutions (FAR) [5]. A free sorting task was applied to categorize FAR according to their similarities or dissimilarities, and different clusters were highlighted. Instrumental analysis of the different FAR and wines demonstrated variations in their molecular composition. Results obtained from sensory and gas chromatography analysis enrich the knowledge of the fruity expression of red wines from “new” grape varieties opening up new perspectives in wine technology, including blending, thus providing new tools for producers.

Climate and the evolving mix of grape varieties in Australia’s wine regions

The purpose of this study is to examine the changing mix of winegrape varieties in Australia so as to address the question: In the light of key climate indicators and predictions of further climate change, how appropriate are the grape varieties currently planted in Australia’s wine regions? To achieve this, regions are classified into zones according to each region’s climate variables, particularly average growing season temperature (GST), leaving aside within-region variations in climates. Five different climatic classifications are reported. Using projections of GSTs for the mid- and late 21st century, the extent to which each region is projected to move from its current zone classification to a warmer one is reported. Also shown is the changing proportion of each of 21 key varieties grown in a GST zone considered to be optimal for premium winegrape production. Together these indicators strengthen earlier suggestions that the mix of varieties may be currently less than ideal in many Australian wine regions, and would become even less so in coming decades if that mix was not altered in the anticipation of climate change. That is, grape varieties in many (especially the warmest) regions will have to keep changing, or wineries will have to seek fruit from higher latitudes or elevations if they wish to retain their current mix of varieties and wine styles.

A predictive model of spatial Eca variability in the vineyard to support the monitoring of plant status

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.19.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...

Evaluation of climate change impacts at the Portuguese Dão terroir over the last decades: observed effects on bioclimatic indices and grapevine phenology

In the last decades the growers of the Portuguese Dão winegrowing region (center of Portugal) are experiencing changes in climate that are influencing either grape phenology berry health and ripening. Aiming to study the relationships between climate indices (CI), seasonal weather and grapevine phenology, in this work long-term climate and phenological data collected at the experimental vineyard of the Portuguese Dão research centre between 1958 and 2019 (61 years) for the red variety Touriga Nacional, was analyzed. The trends over time for the classical temperature-based indices (Growing Season Temperature – GST -, Growing Degree Days – GDD, Huglin Index – HI and Cool Night Index – CI) presented a significantly positive slope while the Dryness Index (DI) showed a negative trend over the last 61 years. Regarding grapevine phenology, an average advance of 4.5 days per decade in the harvest day was observed throughout the last 61 years. Consequently, the weather conditions during the ripening period have changed, showing an increasing trend over time in the average temperature (higher magnitude in the maximum than in the minimum temperature) and a decrease in the accumulated rainfall. A regression analysis showed that ~50% of harvest date variability over years was explained by the temperature-based indices variability. These observed effects of climate change on bioclimatic indices and corresponding anticipation of harvest date can still be considered advantageous for the Dão terroir as it allows to achieve an optimal berry ripening before the common equinox rains and, therefore, avoid the potential negative impacts of the rainfall on berry health and composition.

Spatial determination of areas in the Western Balkans region favorable for organic production

In problematic conditions for production of grapes and wine caused by the COVID-19 pandemic and the resulting occurrence of wine surpluses, producers are increasingly turning to the innovative viticulture and winemaking of products that are more appealing to the market and the consumers. On the other hand, consumption of the food safety or organic products, and therefore of organic grapes and wine, is increasingly common in the world, in particular in Europe. The Regional Rural Development Standing Working Group (SWG RRD), as a regional intergovernmental organization gathers actors in the viticulture and winemaking sector from states and territories of the Western Balkans (South-East Europe) in the Expert Working Group for Wine, with the aim of improving viticulture and winemaking in this region through joint activities. In accordance with the aforementioned, the SWG RRD is working on advancing organic production of grapes and wine, and on recognition of specificities of the terroir of wine-growing areas in Western Balkans. In addition, as part of the project “Facilitation of Exchange and Advice on Wine Regulations in Western Balkan Countries” helmed by the German Federal Ministry of Food and Agriculture, in addition to harmonization of relevant legislation with EU regulations, efforts are being invested towards recognition of organic wines. Within activities and project implemented by this organization, expert analyses and scientific research of the terroir of Western Balkans were carried out, and some of the results are presented in this paper.