PT  - JOURNAL ARTICLE
AU  - Gianluca Allegro
AU  - Ana B. Bautista-Ortín
AU  - Encarna Gómez-Plaza
AU  - Chiara Pastore
AU  - Gabriele Valentini
AU  - Ilaria Filippetti
TI  - Impact of Flavonoid and Cell Wall Material Changes on Phenolic Maturity in cv. Merlot (<em>Vitis vinifera</em> L.)
AID  - 10.5344/ajev.2018.18011
DP  - 2018 Jul 05
TA  - American Journal of Enology and Viticulture
PG  - ajev.2018.18011
4099  - http://www.ajevonline.org/content/early/2018/06/29/ajev.2018.18011.short
4100  - http://www.ajevonline.org/content/early/2018/06/29/ajev.2018.18011.full
AB  - In black berry varieties, the changes of flavonoid concentration and composition occurring in the last weeks before harvest can only in part explain the improvement of sensory attributes that are linked with the progression of ripening. This study aimed to better understand the factors involved in the phenolic maturity of cv. Merlot. To achieve this goal, total and extractable anthocyanins and tannins were analyzed in late ripening and the properties of skin cell wall material were determined. Over two consecutive years, both total and extractable anthocyanins increased until harvest, while minor variations in tannin concentration were found. A higher affinity of cell wall material for a commercial seed tannin was observed in the last ripening phases, involving preferentially high molecular mass tannins and galloylated forms. The increase in anthocyanins could allow a more highly colored wine to be obtained with the progression of ripening, and besides, the increasing affinity of skin cell wall material for seed tannins may play a role in the reduction of astringency. This research shows how different factors could influence phenolic maturity, confirming the original insights about this matter in cv. Merlot.