Monoterpenes in cv. Zilavka Free-Run Musts from Prefermentatively Macerated Pomace
Five free volatile monoterpenes (linalool, α-terpineol, citronellol, nerol, and geraniol; FVmT) in free-run musts obtained from crushed grapes of white cv. Zilavka in two consecutive vintages (2011 and 2012) were quantified with headspace solid phase microextraction gas chromatography-mass spectrometry. Unexpectedly high concentrations of the analyzed FVmT were found in free-run musts of Zilavka, a variety of grapes (and wines) not previously described as having high monoterpene content. The most abundant monoterpenes were linalool, α-terpineol, and geraniol, with tens of μg/L of nerol. Citronellol was detectable, but its low concentration was quantified in free-run musts in only one experimental trial. Higher concentrations of the analyzed FVmT were found in the free-run musts obtained in 2012 after hot and dry summer months and an early grape harvest. Increasing maceration temperatures from 6 to 12°C, and then to 20°C during the 20-hr treatment resulted in increased extraction of FVmT. However, only the increases in nerol concentrations were statistically significant with increases found with higher maceration temperatures in both years. The calculated odor activity values for linalool, α-terpineol, and geraniol were relatively high (1.6 to 8). The results indicated monoterpenic potentials of Zilavka. Thus, there is an opportunity for wine producers to consider technological modifications directed to the extraction of FVmT and monoterpene profiling of Zilavka wines.