engleski

Effects of defoliation treatments of grape variety Babica on volatile compounds content in wine

Wine flavour and aroma are derived from a large range of volatile compounds (e.g. esters, aldehydes, ketones, alcohols, terpenes, etc.) and their interactions. The outcome of defoliation on wine volatiles profile was associated with many factors: vegetation period, levels and zones of treatment ; as well as time and weather conditions during harvest.[1] The objective of this two years study (2017 and 2018) was to determine the effects of defoliation on grape variety Babica in condition of warm Mediterranean climate (wine- growing region Dalmatia, Croatia). Defoliation was performed before blooming (BLR), and at the end of verasion (VerLR), observing the concentrations (μg/L) several groups of volatile compounds: monoterpenes ; monoterpenols ; aromatic esters and aromatic alcohols ; aliphatic alcohols ; aliphatic esters ; aldehydes ; and ketones. Volatile compounds were analysed using gas chromatograph (GC) coupled to a mass spectrophotometric (MS) detector along with stir bar sorptive extraction with polydimethylsiloxane phase. Identification of the separated compounds was performed by retention indices and MS spectra compared with mass spectral database. Comparisons of volatile compounds concentrations between different treatments, and between years, were made using analysis of variance (one-way ANOVA) with the least significant different (LSD) test used to examine the means at the p = 0.05 level. The two most abundant volatiles found in wines is 2-methyl-1- butanol and 3-methyl-1-butanol (average concentrations (175.58 and 295.03 μg/L, respectively). Treatments of defoliation significantly increased the concentrations for 2- hydroxy-propanoic acid-ethyl ester and octanoic acid ethyl ester, especially by VerLR, but only in the 2017 year.

wine flavour ; defoliation ; volatiles ; Babica wine

nije evidentirano