Determination of flavour compounds in a mountain cheese by headspace sorptive extraction-thermal desorption-capillary gas chromatography-mass spectrometry

Headspace sorptive extraction (HSSE) combined with thermal desorption (TD), gas chromatography (GC) and mass spectrometric detection (MSD) was applied to determine the volatile compounds of an Italian mountain cheese (Bitto) with protected designation of origin. Samples were taken from local dairy farms in Valtellina (Northern Italy), in which goats and cows were grazing on pastures during summer. A total of 84 compounds that belong to the following chemical families were detected and identified: aldehydes (17), ketones (10), esters (15), fatty acids (12), alcohols (11), terpenes (11) and hydrocarbons (8). The impact of each volatile compound on the flavour profile of Bitto cheese was discussed. The flavour profile of this cheese is important for the producer who wants to claim the right of naming cheese manufactured in a specified restricted area. Actually, this approach might become mainly useful for products, like Bitto cheese, with a PDO registration. HSSE coupled with thermal desorption and GC–MS analysis provided a versatile tool for the analysis of volatiles in cheese.