| Popis: |
The aim of this research was to investigate the influence of off-vine drying of the grapes of Plavac mali cv. on the aromatic compounds of must in the production of traditional dessert wine Prošek. The grapes (23.8° Brix, pH value of 3.76) were harvested in 2009 from the germplasm vineyard of the Institute for Adriatic Crops and Karst Reclamation, and then dried in a greenhouse for 15 days at 21-37 °C. The must obtained from the dried grapes had 35.7° Brix, pH value of 3.87 and total acidity of 8.34 g/L. SPME-GC-MS analysis was used to determine the volatile compounds before and after drying. Total acidity increased 1.96-fold during the process of drying. Thirty-five volatile compounds were determined and quantified. Their relative concentration in the must from dried grapes increased, especially that of terpenes. Among terpenes, the most prevalent were 4- terpineol, linalool, linalool oxide, and cis- and trans-limonene-1, 2-epoxide. Norisoprenoids are products of degradation of carotenoids, among which β-damascenone was found in the must. Among higher alcohols, 3-methyl-1-butanol is quantitatively most significant component. Apart from the effect of concentration due to evaporation, anaerobic metabolism probably influenced the increase of the ratio of volatile compounds. |
