title: Effect of cluster thinning and prohexadione calcium applications on phenolic composition and sensory properties of red wines.
abstract: The overall objective of this study was to investigate the effect of manual cluster thinning (CT) and the application of the growth regulator Prohexadione calcium (ProCa) on the phenolic composition and the sensory profile of Tempranillo and Grenache wines produced from treated vines in La Rioja (Spain). ProCa was applied at preblooming and CT was carried out at veraison in two consecutive years. Different physicochemical parameters and analyses of phenolic compounds were carried out in control, CT and ProCa grapes and wines and wine sensory was performed. Thinning treatments decreased crop yield, besides ProCa application reduced berry size, and berry weight. Color and phenolic composition of Grenache and Tempranillo wines in general were affected by thinning  treatments, with an increase in anthocyanin, flavanol and flavonol concentrations. In sensory analysis, wines obtained from thinned vines presented higher values for several aromatic (e.g., white and yellow fruits, fresh flowers) and taste attributes (i.e., astringency, bitternes, persistence). CT and ProCa treatments resulted in an improvement in wine quality. In general, similar results in phenolic composition, sensory properties and quality of wines were obtained by manual and chemical cluster thinning. ProCa as a growth regulator may be an option for a quality vitiviniculture.
authors.affiliation: Department of Chemistry, University of La Rioja, 53 Madre de Dios, 26006 Logroño, Spain.
authors.forename: José-Miguel
authors.initials: JM
authors.lastname: Avizcuri-Inac
authors.forename: Ana
authors.initials: A
authors.lastname: Gonzalo-Diago
authors.forename: Jesús
authors.initials: J
authors.lastname: Sanz-Asensio
authors.forename: María-Teresa
authors.initials: MT
authors.lastname: Martínez-Soria
authors.forename: Miguel
authors.initials: M
authors.lastname: López-Alonso
authors.forename: Marta
authors.initials: M
authors.lastname: Dizy-Soto
authors.forename: José-Federico
authors.initials: JF
authors.lastname: Echávarri-Granado
authors.forename: Luis
authors.initials: L
authors.lastname: Vaquero-Fernández
authors.forename: Purificación
authors.initials: P
authors.lastname: Fernández-Zurbano
mesh_terms: D000328:Adult; D000872:Anthocyanins / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D003116:Color; D005260:Female; D006801:Humans; D007656:Ketoglutaric Acids / Q000032:analysis / Q000737:chemistry*; D008297:Male; D008875:Middle Aged; D010636:Phenols / Q000032:analysis; D013030:Spain; D013649:Taste / Q000502:physiology*; D027843:Vitis / Q000737:chemistry; D014920:Wine / Q000032:analysis*
chemical_list: D000872:Anthocyanins; D007656:Ketoglutaric Acids; D010636:Phenols; C479018:prohexadione-Ca