terclim by ICS banner
IVES 9 IVES Conference Series 9 EFFECTS OF WINEMAKING FACTORS AND AGEING ON THE POLYPHENOLIC AND COLORIMETRIC PROFILES IN RED WINES PRONE TO COLOUR INSTABILITY

EFFECTS OF WINEMAKING FACTORS AND AGEING ON THE POLYPHENOLIC AND COLORIMETRIC PROFILES IN RED WINES PRONE TO COLOUR INSTABILITY

Abstract

The effects of (A) grape freezing, and (B) malolactic fermentation, have been evaluated on the chemical and colorimetric profiles of red wines from Schiava grossa cv. grapes, thus prone to colour instability. The aim was to observe if specific variables (e.g. grape freezing) could improve the extraction and stability of pigments. The samples were studied from musts up to twelve months in bottle. The study was conducted with independent parallel micro-vinifications (12 = 4 theses x 3 replicates) under strictly-controlled conditions. The measured parameters included: 1) sugars, organic acids and %ABV (measured by specific enzymatic methods or by OIV reference methods), 2) dissolved oxygen (measured according to OIV protocols), 3) semi-quantitative determination of pigments, profile of non-anthocyanidin phenols, and profile of condensed tannins (LC-QqQ/MS [1]), spectrophotometric indexes (Hue and Intensity), colorimetric indexes (CIELab parameters), and the volatile profiles (GCxGC-ToF/MS [2]). A striking relation among the abundances of four anthocyanidin monoglucosides (peonidin-3-glu, malvidin-3-glu, petunidin-3-glu, and cyanidin-3-glu) has been observed in the musts from frozen grapes, but not in wines from frozen or non-frozen grapes. Cyclic procyanidins showed neither significant differences in concentration in must and wine due to any specific applied factor, nor due to specific treatments (such as with bentonites), proving again their applicability as markers for the grape variety in wine [3]. A substantial drop in peonidin-3-glu over the vinification (the main anthocyanin in Schiava cv. grapes) was studied in relation to the applied study factors. Grape freezing increased the extraction of peonidin-3-glu in the must, though the rate of its subsequent loss was faster than in wines from non-frozen grapes. Nonethe-less, peonidin-3-glucoside was still more concentrated in the wines from frozen grapes than in wines from non-frozen grapes up to wine bottling. The wines made from frozen grapes and without malolac-tic fermentation had the highest colorimetric parameters a* (green→red), ΔE* (difference in colour), C* (chromaticity), and ΔH* (difference in tone) colorimetric parameters. b* (blue→yellow) was highest in wines from frozen grapes, but regardless of the application or not of the malolactic fermentation.

 

1. C Dupas de Matos, A., Longo, E., et al. (2020). Foods, vol. 9(4), p. 499
2. Poggesi, S., Dupas de Matos, A., Longo, E., et al. (2021). Molecules, vol. 26(20), p. 6245
3. Longo, E., Rossetti, F., Jouin, A., et al. (2019). Food chemistry, vol. 299, p. 125125

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Edoardo Longo1,2,*,†, Aakriti Darnal1,2, Adriana Teresa Ceci1,2, Simone Poggesi1,2,3, Tanja Mimmo², Emanuele Boselli1,2

1. Oenolab, NOI TechPark Alto Adige/Südtirol, Via A. Volta 13/B, 39100 Bolzano (Italy)
2. Faculty of Agricultural, Environmental and Food Sciences, Free University of Bozen-Bolzano, Piazza Università 5, 39100 Bolzano (Italy)
3. Food experience and sensory testing laboratory (Feast), Massey University, Private Bag 11222, Palmerston North 4410 (New Zealand)

Contact the author*

Keywords

Colour instability, Grape freezing, Chemical profile, Colorimetry

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

Grouping Vitis vinifera grapevine varieties based on their aromatic composition

Climate change is likely to impact wine typicity across the globe, raising concerns in wine regions historically renowned for the quality of their terroir1. Amongst several changes in viticultural practices, replacing some of the planting material (i.e. clones, rootstocks and cultivars) is thought to be one of the most promising potential levers to be used for adapting to climate change. But the change of cultivars also involves the issue of protecting the region’s wine typicity. In Bordeaux (France), extensive research has been conducted on identifying meridional varieties that could be good candidates to help guard against the effects of climate change2 while less research has been done concerning their impacts on Bordeaux wine typicity.

SENSORY CHARACTERIZATION OF COGNAC EAUX-DE-VIE AGED IN BARRELS REPRESENTING DIFFERENT TOASTING PROCESS

Cognac is an outstanding french wine spirit appreciated around the world and produced exclusively in the Nouvelle-Aquitaine region, and more precisely in the Cognac area. According to AOC regulations (Appellation D’origine Controlée), the spirit required at least 2 years of continuous ageing in oak barrels to be granted the title of Cognac. The oak wood will import color, structure and organoleptic complexity. The different steps during barrel-making process, such as seasoning and toasting, influence the above quality attributes in both wines and spirits.

HYDROXYTYROSOL PRODUCTION BY DIFFERENT YEAST STRAINS: SACCHAROMYCES AND NON-SACCHAROMYCES AND THE RELATION WITH THE NITROGEN CONSUMPTION

Hydroxytyrosol (HT) is a phenolic compound with extensive bioactive properties. It is present in olives, olive oil and wines. Its occurrence in wines is partly due to yeast synthetise tyrosol from tyrosine by the Ehrlich pathway, which is subsequently hydroxylated to .
The aim of the present work is to study how different yeast strains can influence in the HT production and, how the different nitrogen consumption of each strain can interfere the production of bioactive compounds.

A NEW SPECIFIC LINEAGE OF OENOCOCCUS OENI IN COGNAC APPELLATION WINES

Oenococcus oeni is the main lactic acid bacteria (LAB) species which conducts the malolactic fermentation (MLF) in wine. During MLF, O. oeni converts malic acid into lactic acid, which modulates wine aroma composition leading to better balanced organoleptic properties. O. oeni is a highly specialized species only detected in environments containing alcohol such as wine, cider or kombucha. Genome analysis of more than 240 strains showed that they form at least 4 main phylogenetic lineages and several sublineages, which are associated with different beverages or types of wines.

INOCULATION OF THE SELECTED METSCHNIKOWIA PULCHERRIMA MP1 AS A BIOPROTECTIVE ALTERNATIVE TO SULFITES TO PREVENT BROWNING OF WHITE GRAPE MUST

Enzymatic browning (BE) of must is caused by polyphenol oxidases (PPOs), tyrosinase and laccase. Both PPOs can oxidize diphenols such as hydroxycinnamic acids (HA) to quinones, which can later polymerize to form melanins [1], which are responsible of BE in white wines and of oxidasic haze in red wines. SO₂ is the main tool used to protect must from BE thanks to its capacity to inhibit PPOs [2]. However, the current trend in winemaking is to reduce and even eliminate this unfriendly additive. Among the different possible alternatives for protecting must against BE, the inoculation with a selected Metschnikowia pulcherrima MP1 is without any doubt one of the most promising ones.