Comparison of Proanthocyanidins with Different Polymerisation Degrees among Berry Skins of ‘Shiraz’, ‘Cabernet Sauvignon’, and ‘Marselan’

Abstract

Proanthocyanidins in grape berries are synthesised mainly before véraison, and very little attention is paid to the evolution of proanthocyanidins (PAs) in grapes from véraison to harvest. The present study focused on the changes of flavan-3-ols with different degrees of polymerisation in grape skins and the difference in proanthocyandin composition of 'Shiraz', 'Cabernet Sauvignon' and 'Marselan' grapes (Vitis vinifera L.). The results show that the content of flavan-3-ols, the percentage of prodelphinidins (%P) and mean degree polymerisation (mDP) found in 'Cabernet Sauvignon' berry skins at post-véraison were higher than those in 'Shiraz' and 'Marselan' skins. Only monomeric, dimeric, trimeric and polymeric flavan-3-ols were detected in the three grape cultivars. Polymers with more than tenfold flavan-3-ol units accounted for a relatively high proportion in grape berry skins, and the content in the three cultivars declined continuously during ripening. Principal component analysis showed that proanthocyanidin content, composition and mDP at grape harvest stage depended strongly on grape cultivar. This study provides some useful information for understanding the accumulation of PAs during berry maturation and this information can be used to improve wine quality.

Changes in Tannin Composition of Syrah Grape Skins and Seeds during Fruit Ripening under Contrasting Water Conditions

“…Among grape phenolic compounds, proanthocyanidins or condensed tannins are responsible for the astringent and bitter properties of the wines and are released from both grape skins and seeds [ 1 , 2 ]. Tannins found in grapesare polymers composed of terminal and extension subunits of flavan-3-ols, mainly(+)-catechin (C), (−)-epicatechin (EC), (−)-epicatechin-3- O -gallate(ECG) and (−)-epigallocatechin (EGC) linked by C(4)-C(6) or C(4)-C(8) interflavanoid bonds [ 3 ]. Grape tannins derived from skins and seeds vary in their relative amount, length, subunit composition and sensory properties.…”

Comparison of Aquitaine and Rioja Red Wines: Characterization of Their Phenolic Composition and Evolution from 2000 to 2013

“…On the other side, low molecular tannin contents were found in the highest concentrations in Graves wines ((+)-catechin, (−)-epicatechin, procyanidin dimers B1 and B3, and procyanidin trimer C1). For Graves samples the predominant grape variety used for blend is Cabernet Sauvignon, in which the percentage of low molecular tannins was higher than in Merlot [ 41 , 44 ], which explains here that “Bordeaux generic” samples, that are mainly assembled with Merlot, show the lowest concentrations in low molecular tannins of all the Aquitaine wine-growing subregions.…”

Επίδραση Αμπελουργικών Τεχνικών Στα Συστατικά Που Διαμορφώνουν Τον Οργανοληπτικό Χαρακτήρα Των Ερυθρών Οίνων

“…Όπου R'=H, R''=OH προκυανιδίνη και όπου R'=OH, R''=OH προδελφινιδίνη (Πηγή: Drinkine et al, 2007) απουσιάζει εντελώς (Hanlin & Downey, 2009). Οι Hanlin & Downey (2009) έχουν προσδιορίσει την επικατεχίνη και την επιγαλλοκατεχίνη ως κύριες επεκτατικές μονάδες, ενώ οι Li et al (2014) αναφέρουν την επιγαλλοκατεχίνη στις ποικιλίες που μελέτησαν.…”

“…Στα γίγαρτα ως κύρια τερματική μονάδα έχει προσδιοριστεί από πολλούς ερευνητές η κατεχίνη και ως κύρια επεκτατική μονάδα η επικατεχίνη (Bordiga et al, 2011;Cohen et al, 2008;Prieur et al, 1994). Ωστόσο, οι Downey et al (2003) (Hanlin & Downey, 2009;Li et al, 2014;Mativvi et al 2008).…”

“…Οι Chira et al (2011) βρήκαν σημαντικές συσχετίσεις με τις κατεχίνη, επικατεχίνη, προανθοκυανιδίνες Β2, Β3, Β4 στους οίνους και με την προανθοκυανιδίνη Β3 στους φλοιούς (Chira et al, 2009). Επιπλέον, οι Li et al, 2014 έχουν συσχετίσει τη συγκέντρωση της επιγαλλοκατεχίνης αρνητικά με τη στυπτικότητα των οίνων. Αντιθέτως, άλλες μελέτες δεν αναφέρουν σημαντικές συσχετίσεις με τις μονομερείς και ολιγομερείς φλαβαν-3-όλες των ραγών και των οίνων (Kallithraka et al, 2011;Quijada-Morin et al, 2012).…”