Principal Component Regression Analysis of the Relation Between CIELAB Color and Monomeric Anthocyanins in Young Cabernet Sauvignon Wines

Abstract

Color is one of the key characteristics used to evaluate the sensory quality of red wine, and anthocyanins are the main contributors to color. Monomeric anthocyanins and CIELAB color values were investigated by HPLC-MS and spectrophotometry during fermentation of Cabernet Sauvignon red wine, and principal component regression (PCR), a statistical tool, was used to establish a linkage between the detected anthocyanins and wine coloring. The results showed that 14 monomeric anthocyanins could be identified in wine samples, and all of these anthocyanins were negatively correlated with the L*, b* and H*ab values, but positively correlated with a* and C*ab values. On an equal concentration basis for each detected anthocyanin, cyanidin-3-O-glucoside (Cy3-glu) had the most influence on CIELAB color value, while malvidin 3-O-glucoside (Mv3-glu) had the least. The color values of various monomeric anthocyanins were influenced by their structures, substituents on the B-ring, acyl groups on the glucoside and the molecular steric structure. This work develops a statistical method for evaluating correlation between wine color and monomeric anthocyanins, and also provides a basis for elucidating the effect of intramolecular copigmentation on wine coloring.

The Importance of Monomeric Anthocyanins in the Definition of Wine Colour Properties

“…Gómez-Míguez et al (2007) observed that Mv3g contributed to the prediction of colour parameters in the pre-fermentative cold maceration of Syrah wines. Han et al (2008Han et al ( , 2009 showed that the structures of anthocyanins influenced their colour values. These all show us that the contributions of anthocyanins to colour are not simply proportional to their contents.…”

“…However, the colour of wines transforms to brick-red as a result of the development of polymeric pigments during maturation and ageing. In red wines made from Vitis vinifera L. grapes there normally are five main monomeric anthocyanins, namely delphinidin-3- O-glucoside, Dp3g;cyanidin-3-O-glucoside, Cy3g;petunidin-3-O-glucoside, Pt3g;peonidin-3-O-glucoside, Pn3g;and malvidin-3-O-glucoside, Mv3g (Gómez-Míguez et al, 2007;Han et al, 2008). Monoglucosides also exist as the acylated forms, including the aliphatic acetyl and the aromatic p-coumaroyl and caffeoyl (He et al, 2012).…”

“…Most studies are based on non-acylated anthocyanins (common anthocyanin monoglucosides in red wines), acylated anthocyanins, pyranoanthocyanins or even the sum of them (Monagas et al, 2005;Gómez-Míguez et al, 2007;Han et al, 2008Han et al, , 2009). Furthermore, they only detected the colour of aqueous solution or model wine containing anthocyanins, not the wine colour (Heredia et al, 1998;Han et al, 2008Han et al, , 2009).…”

Tissue-specific Accumulation of Flavonoids in Grape Berries is Related to Transcriptional Expression of VvF3′H and VvF3′5′H

“…The identification of five basic non-acylated anthocyanins was confirmed by comparison with commercially available anthocyanin standards and the MS/MS spectra. Identification of all the other acylated anthocyanins was achieved mainly by comparing molecular ions and product ions of these anthocyanins with those available in the literature (García-Beneytez et al, 2002Wang et al, 2003;Núñez et al, 2004;De Villiers et al, 2004;Downey & Rochfort, 2008;Han et al, 2008;Cook Papini et al, 2010). The cis and trans isomers of the coumaroylates for peonidin-3-Oglucoside and malvidin-3-O-glucoside were distinguished by elution time and proportion.…”

“…The anthocyanin solution was filtered through a 0.45 μm filter (cellulose acetate and nitrocellulose, CAN) and used for qualitative and quantitative analyses with the help of highperformance liquid chromatography-mass spectrometry (HPLC-MS) (Han et al, 2008). An Agilent 1100 series LC-MSD trap VL, equipped with a DAD detector and reversed phase column (Kromasil C18, 250 × 4.6 mm, 5 μm), was used.…”