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…

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.

Read More

NEW INSIGHTS INTO THE FATE OF MARKERS INVOLVED IN FRESH MUSHROOM OFF-FLAVOURS DURING ALCOHOLIC FERMENTATION

The fresh mushroom off-flavour (FMOff) has been appearing in wines since the 2000s. Some C8 compounds such as 1-octen-3-one, 1-octen-3-ol, 1-hydroxyoctan-3-one, 3-octanol and others are involved in this specific off-flavour [1-3]. At the same time, glycosidic precursors of some FMOff compounds have been identified in musts contaminated by Crustomyces subabruptus [4], highlighting the role of aroma precursors in this specific taint. However, the fate of these volatile molecules and glycosidic fractions during fermentation is not well known.

Read More

FLAVONOID POTENTIAL OF MINORITY RED GRAPE VARIETIES

The alteration in the rainfall pattern and the increase in the temperatures associated to global climate change are already affecting wine production in many viticultural regions all around the world (1). In fact, grapes are nowadays ripening earlier from a technological point of view than in the past, but they are not necessarily mature from a phenolic point of view. Consequently, the wines made from these grapes can be unbalanced or show high alcohol content. Dramatic shifts in viticultural areas are currently being projected for the future (2).

Read More

RED WINE AGING THROUGH 1H-NMR METABOLOMICS

Premium red wines are often aged in oak barrel. This widespread winemaking process is used, among others, to provide roundness and complexity to the wine. The study of wine evolution during barrel aging is crucial to better ensure control of wine quality.
¹H-NMR has already been proved to be an efficient tool to monitor winemaking process [1]. Indeed, it is a non-destructive technique, it requires a small amount of sample and a short time of analysis, yet it provides clues about several chemical families.

Read More

THE EFFECT OF BENTONITE FINING ON THE VOLATILE AND NON-VOLATILE PROFILE OF ITALIAN WHITE WINES

Marselan wines have an unusual high proportion of seed derived tannins from grapes having high proportions of skins, which are rich in tannins. But the causes behind this characteristic have not yet been identified. In vintage 2023 wines were made at experimental scale (9 kg by experimental unit) from Arinarnoa, Marselan and Tannat Vitis vinifera grape cultivars by traditional maceration, and by techniques aimed to increase the wine content in skin derived tannin: addition of extraction enzymes, addition at vatting of grape-skin enological tannins, or by extended maceration, known to increase the seed derived tannin contents of wines. Macerations were of 7 days, except in the extended macerations that were of 15 days.

Read More