## 2 Materials and Methods
### Determination of the Sodium Chloride Content (the Mohr Method)  
Approximately 2 g of the raw and cooked GSW and GTW samples were kept in an oven at 105 \({}^{\circ}\)C until their constant weight was reached; then, the samples were soaked in 40 mL of water-ultratrace. Then, the solutions were stirred for 2 h at room temperature, centrifugated for 10 min at 4000 rpm, filtered in 50 mL volumetric flask, and made up to volume with water-ultratrace. The pH of the solution was adjusted with 0.1 N sodium hydroxide up to a value of 8.0. About 2 mL of K\({}_{2}\)CrO\({}_{4}\) indicator was added to 20 mL of solution that was titrated with 0.1 N silver nitrate until endpoint. In parallel, a blank test was carried out by titrating 20 mL of distilled water with 0.1 N silver nitrate until endpoint in the presence of 2 mL of K\({}_{2}\)CrO\({}_{4}\) indicator. By knowing the stoichiometry and moles consumed at the end point, the amount of chloride was determined. From the milligrams of Cl\({}^{-}\) ion, the mg of NaCl of the sample is obtained. Mineralization of Samples and Determination of Micro-Macro Elements: Inductively Coupled Plasma-Optical Emission Spectrometers Analysis ICP-OES  
_Gnocchi_ samples underwent acid digestion according to the method of [PERSON] et al. [8], slightly modified. Five milliliters of HNO\({}_{3}\) and 2.5 mL of H\({}_{2}\)O\({}_{2}\) were added to 0.5 g of dried sample. The mixture was digested at 240 \({}^{\circ}\)C until the solution became transparent, (Heating digester DK VELP Scientifica). After cooling, the solution was diluted with water-ultratrace up to a final volume of 25 mL in a volumetric flask and microfiltrated. The clear and plain solution was analyzed with (ICP-OES). The elemental analysis of macro, micro, and trace elements was performed by ICP-OES with iCAP 7000 Series (Thermo Scientific, Waltham, MA, USA), equipped with ASX-520 autosampler (CETAC(tm). A calibration curve was constructed using a standard mix solution containing all analyzed elements. The final concentration of the elements was expressed as mg element kg\({}^{-1}\) dry weight. Determination of Volatile Compounds by Solid Phase Microextraction Gas Chromatography/Mass Spectrometer Analysis (SPME-GC/MS)  
Volatile compounds of both raw and cooked GTW and GSW samples were determined by solid-phase micro-extraction (SPME) coupled to gas-chromatography/mass spectrometry (GC/MS), according to the modified method of [PERSON] et al. [9]. GTW and GSW samples were cut into pieces of 2-3 mm. For each SPME analysis, 3 g of sample was placed in a 20 mL headspace vial. The sample was allowed to equilibrate at 40 \({}^{\circ}\)C for 5 min at 250 rpm using the automatic sampling system Gerstel MPS2 (Gerstel GmbH & Co., Mulheim, Germany). The analysis was conducted by a GC/MS system (Agilent 7890/5975 Inert, Agilent, Santa Clara, CA, USA) equipped with the above-mentioned autosampler with helium as carrier gas (1.5 mL/min). A coated Divinylbenzene/carboxen/Polydimethylsiloxane (DVB/CAR/PDMS) fiber (Sigma-Aldrich S.r.l., Milan, Italy) was exposed to the headspace of the sample for 30 min maintaining the sample at 40 \({}^{\circ}\)C. The fiber was desorbed for 10 min at 240 \({}^{\circ}\)C in the injection unit, in splitless mode. The separation was carried out in a capillary column HP Innovax (Agilent Technologies, Santa Clara, CA, USA) (30 m \(\times\) 0.25 mm id. \(\times\) 0.50 um film thickness). The GC oven temperature program started at 40 \({}^{\circ}\)C for 3 min, then was ramped to 240 \({}^{\circ}\)C at 5 \({}^{\circ}\)C/min and kept the final temperature for 10 min. The mass spectrometer operated with an ion source at 230 \({}^{\circ}\)C, quadrupole temperature of 150 \({}^{\circ}\)C, 70 eV electron energy, acquiring in TIC mode from m/z 33 to 300 luma. Identification of volatile compounds was achieved by comparing mass spectra with the Wiley library (Wiley7, NIST 05). The proportion of each compound was estimated by dividing its mean area by the total area of the chromatogram and expressed as a percentage.