Discrimination and authentication of geographical origin of Turkish Taşköprü garlic by investigating volatile organosulfur compound profiles and multivariate analyses

Nowadays, counterfeiting and adulteration on foods take place around the world in a variety of ways. Identification and authentication of geographical origin of agricultural products has great importance not only for food safety, but for protection of registrations as well. This study aimed at discriminating the Turkish Taşköprü garlic, possessing protected geographical indication (GI) in Turkey and GI registration from the European Union, from the other samples. For this reason, the combination of headspace-gas chromatography-mass spectrometry (HS-GC-MS) analysis of the volatile organosulfur compounds (VOSCs) and two multivariate analysis techniques, namely hierarchical cluster analysis (HCA) and principal component analysis (PCA), were employed for classifying the garlic samples on the basis of their geographical origin. Discrimination of Taşköprü garlic and the other samples including a suspicious sample imported from China was accomplished by performing two dimensional and three dimensional PCA analyses to relative amounts of VOSCs and also to chromatogram raw data.