Applicazione di tecniche analitiche avanzate nello studio dei composti chimici dell'uva e del vino conservato in botti di legno: il caso del Raboso
Year: 2010
Type: dissertation
Abstract: Raboso Piave and Raboso Veronese are different grape varieties typical of Eastern Veneto, because are characterized by very similar organoleptic characteristics they used in winemaking for production of the wine named “Raboso”. The remarkable similarity of the two varieties, also confirmed by molecular analyses, suggested similar chemical grape profiles. The first step of the thesis was focused to the chemical characterization of two grape varieties by the study of polyphenolic and aromatic compounds, and of seed protein profiles with a new analytical approach by Matrix-Assisted-Laser-Desorpition-Ionization mass spectrometry (MALDI/MS). High amount of flavonoids and anthocyanins extractable with winemaking were found in both varieties, and high quercetin glucoside was found in particular in Raboso Veronese. The anthocyanic profile was characterized by important content of cyanin, and low contents of acylated anthocyanins, the aroma profile by significant presence of glycoside terpenols and norisoprenoids. The MALDI/MS method was proved to be a valuable tool for variety characterization, evidencing different seed protein profiles for the grape varieties studied. The differentiation between Raboso Piave and Veronese was possible in particular on the basis of the anthocyanic profile. The study of aromatic and polyphenolic composition evidenced a particular aptitude for wood aging of Raboso wine. As a consequence, the second step of the study was focused on the wine evolution during storage in wooden barrels. Barrels made with acacia, chestnut, cherry, mulberry and oak were used. The study of volatile and polyphenolic compounds released by the wood in wine and spirit model solutions allowed to identify in hydroalcoholic extracts 51 different volatile compounds, and each type of wood showed a distinctive profile. Chestnut and oak showed the major cession of polyphenolic. Cherry had high content of polyphenols but low extractable by the wine and unstable to oxidation so it proved to be the wood least suitable for long time wine aging, while the oak was the most suitable. The study of chemical evolution of wine during nine months of aging showed a significant reduction of fruity-note ethyl esters and ethylguaiacol and a large supply of ethylphenol in the mulberry barrel aged wine, indicating this wood as less suitable for aging of wines.
Author: Mirko De Rosso
Language: Italian
Subfield: Food Science
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W183701721