Total polyphenols contents in different grapevine varieties in highlands of southern brazil

Abstract

Phenolic compounds are one of the main parameters of wine quality and contribute to the organoleptic characteristics, particularly color, astringency and body. In the highlands of southern Brazil, low temperatures and high accumulation of global solar radiation favor the synthesis of total polyphenols in grapes. The objective of this work was to evaluate the concentration of total polyphenols of 10 white varieties and 13 red varieties produced in high altitude regions of southern Brazil. The vineyard is located in the Experimental Station of Santa Catarina State Agricultural Research and Rural Extension Agency (EPAGRI), in the city of São Joaquim (28° 16^′30″S, 49° 56^′09″W, Altitude 1,400 m), the evaluations occurred in 2015/2016 growing season. The content of total polyphenols was determined as proposed by Singleton & Rossi (1965), using the Folin-Ciocalteu method, with spectrophotometer readings. Polyphenol content ranged from 283.56 to 1,387.31 mg/L for white varieties, the varieties with the highest concentrations were Greco di Tufo (1,378.31 mg/L), Trebbiano Toscano (995.59 mg/L) and Ribola Gialla (737.48 mg/L). For the red varieties, the total polyphenol content ranged from 523.87 to 4,929.57 mg/L, Ancellotta (4,929.57 mg/L), Uva di Troia (2,722.27 mg/L) and Croatina (2,410 mg/L) stood out for presenting the highest levels.