| Abstract
| - The aim of the present work was to specify the influence of the polymerization degree on the colorstability of anthocyanins using model solutions under higher thermal conditions simulating rapid foodaging. Results showed that an increase in polymeric degree improves the color stability of oenin.Solutions containing a catechin tetramer, purified from brown rice, displayed a remarkable stability.Flavanols as monomers, (+)-catechin and (−)-epicatechin, appeared to decrease stability with theformation of a xanthylium salt leading to yellowish solutions. For the dimers, procyanidin B2 and B3,different behaviors on red color stability have been observed corresponding to their differentsusceptibility to cleavage upon heating. In the presence of the trimeric procyanidin C2, the red colorappeared more stable. However, the HPLC chromatograms showed a decrease in the amplitude ofthe peaks of oenin and procyanidin C2. Concomitantly, a new peak appeared with a maximalabsorption in the red region. This newly formed pigment probably came from the condensation ofoenin and procyanidin C2. Keywords: Oenin; anthocyanins; flavanols; procyanidins; condensed tannins; color stability; copigmentation; stacking; condensation; xanthylium; new pigment
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