Ammonia. For each parameter, a certain kit (Sinatech, Fermo, Italy) was utilised. Ethanol was analyzed

Ammonia. For each parameter, a certain kit (Sinatech, Fermo, Italy) was utilised. Ethanol was analyzed with an Alcolyzer dma 4500 (Anton Paar, Graz, Austria). two.3. Analysis of Volatile Compounds For quantification of alcohols, esters, fatty acids, and benzenoids (except methyl salicylate), SPE extraction followed by GC-MS evaluation was used, following the procedure described by Slaghenaufi et al. [4]. An quantity of 100 of internal common 2-octanol (four.two mg/L in ethanol) was added to samples ready with 50 mL of wine and diluted with 50 mL of deionized water. Samples were loaded onto a BOND ELUT-ENV, SPE cartridge (Agilent Technologies. Santa Clara, CA, USA) previously activated with 20 mL of dichloromethane, 20 mL of methanol and equilibrated with 20 mL of water. Immediately after sample loading, the cartridges had been washed with 15 mL of water. Absolutely free volatile compounds were eluted with ten mL of dichloromethane, after which concentrated beneath gentle nitrogen stream to 200 before GC injection.Foods 2021, ten,four ofFor quantification of terpenes, norisoprenoids, lactones and methyl salicylate, SPME extraction followed by GC-MS analysis was utilised, following the procedure described by Slaghenaufi et al. (2018) [32]. An amount of five of internal typical 2-octanol (4.two mg/L in Ethanol) was added to five mL of wine diluted with 5 mL of deionized water inside a 20 mL glass vial. An volume of 3 g of NaCl was added before GC-MS evaluation. Samples were equilibrated for 1 min at 40 C. Subsequently SPME extraction was performed making use of a 50/30 divinylbenzene arboxen olydimethylsiloxane (DVB/CAR/PDMS) fiber (Supelco, SM-360320 In Vitro Bellafonte, PA, USA) exposed to sample headspace for 60 min. GC-MS analysis was carried out on an HP 7890A (Agilent Technologies) gas chromatograph coupled to a 5977B quadrupole mass spectrometer, equipped using a Gerstel MPS3 auto sampler (M lheim/Ruhr, Germany). Separation was performed employing a DB-WAX UI capillary column (30 m 0.25, 0.25 film thickness, Agilent Technologies) and helium (six.0 grade) as carrier gas at 1.two mL/min of continual flow rate. GC oven was programmed as follows: began at 40 C for three min, raised to 230 C at four C/min and maintained for 20 min. Mass spectrometer was operated in electron ionization (EI) at 70 eV with ion source temperature at 250 C and quadrupole temperature at 150 C. Mass spectra were acquired in synchronous Scan (m/z 4000) and SIM mode. Samples had been analyzed in random order. Calibration curves were prepared for both quantification techniques. For SPE-GC-MS approach, a calibration curve was ready for each analyte employing seven concentration VU0422288 Epigenetic Reader Domain points and three replicate solutions per point in model wine (12 v/v ethanol, three.five g/L tartaric acid, pH 3.5) 100 of internal normal 2-octanol (four.two mg/L in ethanol) was added to every calibration solution, which was then submitted to SPE extraction and GC-MS analysis as described for the samples. For SPME-GC-MS technique a calibration curve was prepared for every analyte working with seven concentration points and 3 replicate solutions per point in red wines. An level of five of internal requirements 2-octanol (4.2 mg/L in ethanol) was added to every calibration solution, which was then submitted to SPME extraction and GC-MS evaluation as described for the samples. Calibration curves have been obtained working with Chemstation software program (Agilent Technologies, Inc.) by linear regression, plotting the response ratio (analyte peak area divided by internal standard peak region) against concentration ratio (added analyte conce.