title: Phenylalanine and urea foliar applications to grapevine: effect on wine phenolic content.
abstract: Phenolic compounds play a key role in the organoleptic properties of wines. Viticultural practices may influence grape and wine phenolic content, thus determining their quality. The objective of this study was to evaluate the effect of foliar applications of phenylalanine and urea, at two different doses, on wine phenolic composition. Grapes were harvested at their optimal technological maturity and their respective wines were elaborated at small scale. Wine detailed phenolic composition was determined. Results revealed that the content of several anthocyanins and flavonols was enhanced by the application of both phenylalanine doses and by the application of the low dose of urea. In contrast, flavanols and non-flavonoid compounds were less affected by the foliar treatments. The findings seem to be related to the time of application, since anthocyanins and flavonols are accumulated after veraison. In conclusion, nitrogen foliar fertilization increased the phenolic content of Tempranillo wines. This could be of interest since anthocyanins and flavonols are associated with wine quality, especially with its color.
authors.affiliation: Instituto de Ciencias de la Vid y del Vino (Gobierno de La Rioja-CSIC-Universidad de La Rioja), Ctra. Mendavia-Logroño NA 134, Km. 90, 26071 Logroño, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Portu
authors.affiliation: Instituto de Ciencias de la Vid y del Vino (Gobierno de La Rioja-CSIC-Universidad de La Rioja), Ctra. Mendavia-Logroño NA 134, Km. 90, 26071 Logroño, Spain.
authors.forename: L
authors.initials: L
authors.lastname: González-Arenzana
authors.affiliation: Instituto Regional de Investigación Científica Aplicada, Universidad de Castilla-La Mancha, Campus Universitario s/n, 13071 Ciudad Real, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Hermosín-Gutiérrez
authors.affiliation: Instituto de Ciencias de la Vid y del Vino (Gobierno de La Rioja-CSIC-Universidad de La Rioja), Ctra. Mendavia-Logroño NA 134, Km. 90, 26071 Logroño, Spain.
authors.forename: P
authors.initials: P
authors.lastname: Santamaría
authors.affiliation: Instituto de Ciencias de la Vid y del Vino (Gobierno de La Rioja-CSIC-Universidad de La Rioja), Ctra. Mendavia-Logroño NA 134, Km. 90, 26071 Logroño, Spain. Electronic address: Teresa.GardeCerdan@gmail.com.
authors.forename: T
authors.initials: T
authors.lastname: Garde-Cerdán
mesh_terms: D000872:Anthocyanins / Q000032:analysis; D010636:Phenols / Q000032:analysis*; D010649:Phenylalanine; D014508:Urea / Q000737:chemistry*; D027843:Vitis / Q000737:chemistry*; D014920:Wine / Q000032:analysis*
chemical_list: D000872:Anthocyanins; D010636:Phenols; D010649:Phenylalanine; D014508:Urea
keywords: Anthocyanins; Flavonols; Nitrogen; Tempranillo; Vitis vinifera L.; Wine