IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Asymmetrical flow field-flow fractionation with online multidetection is a viable tool to investigate colored red wine colloids

Asymmetrical flow field-flow fractionation with online multidetection is a viable tool to investigate colored red wine colloids

Abstract

Despite its relevance for wine quality and stability, red wine colloids have not still been sufficiently investigated, an occurrence due to the lack of suitable analytical techniques to study them as they are present in wine. Recently, asymmetrical Flow Field-flow Fractionation (AF4) with online multidetection has been tested as a new analytical tool to this aim, revealing its suitability for quantification, fractionation, and characterization of wine colloids in native state [1]. With the aim to characterize red wines in relation to their colloidal composition, AF4 technique was applied to 24 monovarietal Italian wines kept in bottles for 2 years and produced without any filtration, oak contact, fining treatments, malolactic fermentation or ageing on yeast lees. AF4 analysis allowed to quantify wine colloids, and to characterize them in terms of dimensions (by MALS) and absorbance (A280 & A520 nm). MALS revealed that each wine contained several colloids’ populations of different sizes (from 10 to 130 nm), but most of them showed sizes in the range 20 – 40 nm. The comparison by AF4 analysis of the A280-absorbing species present in whole wines with that of wines containing only species larger than 5 kDa (which were considered as colloids) allowed to calculate for each wine the percentage of molecules involved in the assembly of colloidal particles. This calculation showed that in the different samples the percentage of colloids varied from 1 to 44% of the total A280 absorbing compounds, indicating the diversity of the wines. Given that the A280 signal is mostly due to phenolics and proteins, these data indicate that very different percentages of these compounds participate in the formation of particles in the 20 – 40 nm size range. This means that phenolics necessarily need to be associated with other wine components to form particles of those dimensions. This association should involve proteins and polysaccharides [1]. The A520 data indicated the presence of pigments in the colloidal fraction. These pigments are likely to be constituted of tannin-anthocyanins complexes (polymeric pigments). Therefore, given the absence of species with sizes <20 nm, an association of these colored complexes with other colloidal-forming compounds seems necessary, the obvious candidate being proteins as they are known to strongly interact with tannins. Our results suggest that the color of red wines is due, in addition to free oligomeric pigments, also to colloidal particles formed by these latter bound to proteins, and that the quantity of these particles is highly variable in wines from different origin. How the presence of proteins affects the stability and evolution of red wines’ color remains to be investigated, keeping into consideration also the contribution of wine polysaccharides, which have been previously found to be part of the red wine colloidal particles [1].

References

[1] Marassi, et al. Food Hydrocoll 2021;110:106204.
Acknowledgments: MIUR project PRIN n.20157RN44Y

DOI:

Publication date: June 23, 2022

Issue: IVAS 2022

Type: Article

Authors

Marangon Matteo1, Marassi Valentina2, Roda Barbara2, Zattoni Andrea2, Reschiglian Pierluigi2, Mattivi Fulvio3,4, Moio Luigi5, Parpinello Giuseppina Paola6, Piombino Paola5, Río Segade Susana7, Rolle Luca7, Slaghenaufi Davide8, Versari Andrea6, Vrhovsek Urska4, Ugliano Maurizio8 and Curioni Andrea1

1Department of Agronomy, Food, Natural Resources, Animals and Environment (DAFNAE), University of Padova, Italy
2Department of Chemistry “G. Ciamician”, University of Bologna, Italy
3Department of Cellular, Computational and Integrative Biology – CIBIO, University of Trento, Italy
4Department of Food Quality and Nutrition, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all’Adige, Italy
5Department of Agricultural Sciences, Division of Vine and Wine Sciences, University of Napoli Federico II, Italy
6Department of Agricultural and Food Sciences, University of Bologna, Italy
7Department of Agricultural, Forest and Food Sciences, University of Torino, Italy
8Department of Biotechnology, University of Verona, Italy

Contact the author

Keywords

red wine, colloids, proteins, polysaccharides, phenolics

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

OTA DEGRADATION BY BACTERIAL LACCASEST

Laccases from lactic acid bacteria (LAB) are described as multicopper oxidase enzymes with copper union sites. Among their applications, phenolic compounds’ oxidation and biogenic amines’ degradation, have been described. Besides, the role of LAB in the toxicity reduction of ochratoxin A (OTA) has been reported (Fuchs et al., 2008; Luz et al., 2018). Fungal laccases, but not bacterial laccases, have been screened for OTA and mycotoxins’ degradation (Loi et al., 2018). OTA is a mycotoxin produced by some fungal species, such as Penicillium and Aspergillus sp., which infect grape bunches used for winemaking.

Caracterización sensorial y preferencias de los consumidores en vinos de crianza biológica elaborados a diferente graduación alcohólica

Las tendencias actuales del mercado apuntan hacia el consumo de vinos con menor contenido en alcohol, y, por otra parte, de vinos con características especiales y diferenciadoras, siendo los vinos con indicación geográfica o denominación de origen los más demandados.

Is wine terroir a valid concept under a changing climate?

The OIV[i] defines terroir as a concept referring to an area in which collective knowledge of the interactions between the physical and biological environment (soil, topography, climate, landscape characteristics and biodiversity features) and vitivinicultural practices develops, providing distinctive wine characteristics. Those are perceptible in the taste of wine, which drives consumer preference and, therefore, wine’s value in the marketplace. Geographical indications (GI) are recognized regulatory constructs formalizing and protecting the nexus between wine taste and the terroir generating it. Despite considering updates, GIs do not consider the nexus as a dynamic one and do not anticipate change, namely of climate. Being climate a fundamental feature of terroir, it strongly impacts wine characteristics, such as taste. According to IPCC[ii], many widespread, rapid and unprecedented changes of climate occurred, some being irreversible over hundreds to thousands of years. Climatic shifts and atmospheric-driven extreme events have been widely reported worldwide. Recent climatic trends are projected to strengthen in upcoming decades, whereas extremes are expected to increase in frequency and intensity, forcing wines away from GI definitions. Geographical shifts of viticultural suitability are projected, often moving into regions and countries different from current ones. Some authors propose adaptation in viticulture, winemaking and product innovation. We show evidence of climate changing wine characteristics in the Douro valley, home of 270-year-old Port GI. We discuss herein resist or adapt stances for when climate changes the nexus between terroir and wine characteristics. Using the MED-GOLD[iii] dashboard, a tool allowing for easy visual navigation of past and future climates, we demonstrate how policymakers can identify future moments, throughout the 21st century under different emission scenarios, when GI specifications will likely need updates (e.g., boundaries, varieties) to reduce climate-change impacts.

Zonage viticole des surfaces potentielles dans la vallée Centrale de Tarija (Bolivie)

La présente étude de zonage viticole a été faite dans la région de la vallée Central de Tarija(VCT), dans la ville de Tarija, au Sud de la Bolivie; une région avec plus de 400 années de tradition qui présente une vitiviniculture de haute qualité. La Vallée possède une surface total de 332 milles ha.; existant des vignobles entre 1660 y 2300 m.s.n.m. et dans ce rang d’altitude il existe 91 mille ha.

Interaction between commercial mannoproteins and phenolic compounds of two red wines from different Portuguese grape cultivars

The interaction between mannoproteins and wine phenolic compounds is a subject of great interest as some studies show the possible impact in color stability and an improvement in the sensory characteristics namely the reduction of red wine astringency.