Study on the Use of Evolved Gas Analysis FT-IR (EGA FT-IR) for the Evaluation of Cheese Volatile Fraction

The analysis of volatile compounds for food products characterization is currently performed by gas chromatographic separation, often coupled with mass spectrometry. In our research the possibility of the application of the Fourier-transform infrared spectroscopy (FT-IR) technique to the cheese volatile fraction evaluation was investigated. An Evolved Gas Analysis (EGA) FT-IR prototype, developed to detect some volatile molecules released from bottle grade PET, was used. The preliminary step of the work was devoted to the set up of the best analytical conditions and instrumental parameters for cheese analysis. Thirty nine samples of PDO Bitto cheeses were analysed by both EGA FT-IR and Solid Phase Microextraction/Gaschromatography/Mass Spectrometry (SPME/GC/MS) technique. Satisfactory correlations were observed between the FT-IR spectra and the most abundant compounds detected by SPME/GC/MS. Even though some aspects of the analytical conditions need to be improved, the results obtained are promising for a possible application of EGA FT-IR in the evaluation of volatile fraction of foods.