SPME GC-MS monitoring of volatile organic compounds to assess typicity of Pecorino di Carmasciano ewe-milk cheese

The sensory traits of Pecorino di Carmasciano (PdC), an artisanal ewe-milk cheese produced in Irpinia (Southern Italy), are believed to arise from grazing grass growing on a soil rich in sulphurated compounds. Volatiles of nine PdC samples obtained by solid-phase microextraction gas chromatography-mass spectrometry have been compared to those of six common ewe-milk cheese samples. Amongst 82 volatiles identified, no sulphur compound was detected in any PdC sample, excepting traces of dimethyl sulphone. Principal component analysis (PCA) did not distinguish PdC and commercial samples. Thus, the typicality of PdC should be attributed to a combination of biotic and abiotic factors.