Gas Sensors Modified with Zeolite y for Assessing Wine Aroma Compounds

The present work develops a MOS-based e-nose with sensors modified with zeolite Y. For this purpose, the following SnO₂ doped with Pd and/or Pt have been prepared: M1 ((0.25 Pd/0.75 Pt)/SnO₂), M2 ((0.50 Pd/0.50 Pt)/SnO₂), M3 ((0.75 Pd/0.25 Pt)/SnO₂), Pd/SnO₂, and Pt/SnO₂, at the total concentrations of the noble metals of 0.1% and 0.2% for use in gas sensors and be part of the electronic nose. Then, the sensors were assembled with the oxides using the screen printing method. Different electronic noses of four sensors were prepared by combining tin oxides doped with palladium and/or platinum and zeolite Y. The physicochemical characterization of oxides using FRX, FTIR, sorption of N₂, and RAMAN has been performed. Measurements for the detection of wine volatile compounds such as ethanol, methanol, 1-phenyl ethanol, propionic acid, and acetic acid were carried out with these sensors located in a gas chamber and using a program that includes the Labview software, which serves to automate the sensing process. It was found that the sensors modified with zeolite were the ones that in general had higher detections of volatile compounds and PCAs showed positive correlations only for ethanol and the mixture of ethanol at 12% and methanol at 3%. This is related to better detection of these sensors.