## 2 Materials and Methods
### UHPLC-MS Analysis of the Non-Anthocyanine Phenolic Profiles in Pinot Noir and Pinot Gris Wines  
The applied method was slightly adapted from published reports [6]. The LC-MS analysis of the non-anthocyanin polyphenols has been carried out on a UHPLC-QqQ/MS instrument (Agilent LC/TQ 6465 system) equipped with a 1260 Infinity II UHPLC with a quaternary pumps system, a 1260 Infinity II WR PDA detector, in series with an AJS ESI QqQ mass analyzer. The chromatographic separations have been carried out on a Poroshell 120, SB-C18 2.1 mm \(\times\) 100 mm \(\times\) 2.7 \(\upmu\)m (Agilent Technologies Italia, Milan) kept at 30 \({}^{\circ}\)C at a 0.35 mL/min flow rate. The mobile phase consisted of (A) 0.1% formic acid in degassed ultrapure water and (B) 0.1% formic acid in acetonitrile. All used solvents and mobile phase additives were at MS grade. The gradient separation program was as follows: 1%B from 0 to 1.5 min, 1 to 30% B from 1.5 to 19 min, 30 to 99% B from 19 to 20 min, 99% B from 20 to 24 min, 99 to 1% B from 24 to 25 min, and 1% B from 25 to 30 min. The injection volume was 5 \(\upmu\)L. The PDA detector was set to record the absorbance in the 200-700 nm wavelength range using a 4 s response time (1.25 Hz) and 4 nm slit width, with 1 nm spectrum steps. The MS detection was carried in ESI- ionization mode, with the following parameters: mass range = \(m\)/z 200-750, scan time = 500, step size = 0.1 amu, fragmentor potential = 135 V, cell acceleration = 5 V, N\({}_{2}\) gas temperature = 260 \({}^{\circ}\)C, N\({}_{2}\) gas flow = 4 L/min, nebulizer pressure = 35 psi, sheath gas heater = 300 \({}^{\circ}\)C, sheath gas flow = 12 L/min, capillary voltage = \(-\)2500 V, and nozzle voltage = \(-\)500 V.  
Tentative compound identification was carried out by full-scan mass spectrometry determination and the relative PDA \(\uplambda\)max assignment, to classify the compounds at least in a phenolic class, where a complete identification could not be achieved. Solutions of standard compounds (gallic acid, trans-caffeic acid, p-coumaric acid, trans-caftaric acid, (+)-catechin, (-)-epicatechin, protocatechuric acid, astilbin, kaempfer-3-O-glucoside, and procyanidin B2) were analyzed by standard injection, and their PDA spectra, MS/MS spectra, and retention times (min) were used as references. Targeted MS/MS fragmentation experiments (product ions monitoring--PRM) on selected ions were carried out with the following setup: source parameters as in the MS1 analysis, acquisition mass range from \(m\)/z 25 to + 10 \(m\)/z from the selected precursor ion, scan time = 125 ms, fragmentor potential = 135 V, collision energy = 25 V, and cell accelerator 5 V.  
Oligomeric proanthocyanidins (PAC) were separately analyzed on the same UHPLC-QqQ/MS instrument (Agilent LC/TQ 6465 system). The chromatographic separation was carried out on a Vertex Plus Eurosphere II (KNAUER, Berlin, Germany) column (4.6 mm \(\times\) 250 mm \(\times\) 5 \(\upmu\)m) with a precolumn, and kept at 30 \({}^{\circ}\)C. The separation was carried out at a 0.7 mL/min flow rate. The mobile phases consisted of (A) 0.1% formic acid in degassed ultrapure water and (B) 0.1% formic acid in acetonitrile. All solvents and mobile phase additives were at MS grade. The gradient separation program was 1%B from 0 to 2.5 min, 1 to 25%B from 2.5 to 50 min, 25 to 99%B from 50 to 51 min, 99%B from 51 to 55 min, 99 to 1%B from 55 to 56 min, and 1%B from 56 to 62 min. The injection volume was 5 \(\upmu\)L. The mass spectrometer operated in ESI+ mode. The detection of the proanthocyanidins was performed in single-ion monitoring (SIM) mode. In Supplementary File S1--Table S14, the targeted SIM parameters for acquisition for both wines are listed.