## Materials and Methods
### Analysis of Volatile Aroma Compounds by GC\(\times\)GC-TOF-MS  
A volume of 2.5 mL of wine was transferred to a 20 mL headspace vial and 1.5 g of sodium chloride was added. Wine sample was spiked with 50 \(\upmu\)L of internal standard (2-octanol, 1 mg/L). Quality control samples (QC) were prepared by mixing equal proportion of each sample and were analyzed before the samples sequence (\(n=5\)) and after every five samples (\(n=1\)). GC\(\times\)GC-TOF-MS analysis of wines was performed using a GC Agilent 7890N (Agilent Technologies, Palo Alto, CA, USA) coupled to a LECO Pegasus IV time-of-flight mass spectrometer (TOF-MS) (Leco Corporation, St. Joseph, MI, USA) equipped with a Gerstel MPS autosampler (GERSTEL GmbH & Co. KG, Mulheim am der Ruhr, Germany), as described in previous studies with minor modifications [9; 31; 32]. Briefly, samples were preconditioned at 35 \({}^{\circ}\)C for 5 min and volatile compounds were extracted using a DVB/CAR/PDMS SPME fiber for 20 min. Volatile compounds were desorbed for 3 min at 250 \({}^{\circ}\)C in splitless mode. The fiber was reconditioned for 7 min at 270 \({}^{\circ}\)C between each extraction. Helium was used as a carrier gas at a flow rate of 1.2 mL/min. The oven was equipped with a 30 m \(\times\) 0.25 mm \(\times\) 0.25 \(\upmu\)m film thickness VF-WAXms column (Agilent Technologies) in the first dimension (1D) and a 1.5 m \(\times\) 0.15 mm \(\times\) 0.15 \(\upmu\)m film thickness Rxi 17 Sil MS column (Restek) in the second dimension (2D). Initial oven temperature was maintained at 40 \({}^{\circ}\)C for 4 min, then raised at 6 \({}^{\circ}\)C/min to 250 \({}^{\circ}\)C, and then finally maintained at this temperature for additional 5 min. The second oven was maintained at 5 \({}^{\circ}\)C above the temperature of the first one throughout the analysis. The modulator was offset by +15 \({}^{\circ}\)C in relation to the secondary oven, the modulation time was 7 s with 1.4 s of hot pulse duration, as described previously [31]. Electron ionization at 70 eV was applied, the temperature of ion source was 230 \({}^{\circ}\)C, detector voltage was 1317 V, mass range (_m/z_) was 40-350, acquisition rate was 200 spectra/s, and acquisition delay was 120 s.  
Baseline correction, chromatogram deconvolution and peak alignment were performed using LECO ChromaTOF software version 4.32 (Leco Corporation, St. Joseph, MI, USA). The baseline offset was set to 0.8 and signal to noise (S/N) ratio was set at 100. Peak width limits were set to 42 s and 0.1 s in the first and the second dimension, respectively. Traditional, not adaptive integration was used. The required match (similarity) to combine peaks was set to 650. Under these conditions 1025 putative compounds were detected. Volatile compounds were identified by comparing their retention times and mass spectra with those of pure standards and with mass spectra from NIST 2.0, Wiley 8, and FFNSC 2 (Chromaleont, Messina, Italy) mass spectral libraries, with a minimum library similarity match factor of 750 out of 999. For identification of compounds by comparison with pure standards, a mix of 122 compounds was injected under identical GC\(\times\)GC-TOF-MS conditions. For tentative identification of compounds and/or confirmation of their identities determined as described above, linear retention indices were calculated with respect to the retention times of C\({}_{10}\) to C\({}_{30}\) n-alkanes and compared to those from literature for conventional one-dimensional GC obtained using columns of equal or equivalent polarity (NIST 2.0, Wiley 8, FFNSC 2, VCF, ChemSpider). Three hundred and seventeen (317) volatile aroma compounds were (tentatively) identified in total. Volatile compounds were semi-quantified and their concentrations in \(\mu\)g/L were calculated relative to the internal standard 2-octanol, assuming a response factor equal to one.