SPME/GC-MS Characterization and Comparison of Volatiles of Eleven Varieties of Turkish Cheeses

In this study, the volatile aroma profiles of a variety of economically important cheeses for the Turkish dairy sector were characterized. A total of 75 samples belonging to 11 Turkish cheese varieties, including Civil, Canak, Dil, Divle Tulum, Ezine, Hellim, Malatya, Mihalic, Orgu, Urfa, and Van Otlu, were comparatively studied for their volatile profiles. One hundred and twelve volatile compounds were identified in the cheeses by solid-phase microextraction combined with gas chromatography-mass spectrometry and the results are discussed based on their chemical classes (31 esters, 7 acids, 18 ketones, 3 aldehydes, 24 alcohols, 10 terpenes, and 19 miscellaneous compounds). Esters, ketones, and alcohols were the most abundant classes identified and were highly dependent on the variety of cheese. Principal component analysis was applied to aid the interpretation of the gas chromatography-mass spectrometry data and to distinguish the cheeses. Divle Tulum cheese had high levels of aldehydes, ketones, and alcohols and separated from all the other cheeses, and the cheeses including Dil, Hellim, Malatya, Orgu, and Urfa grouped together. The last group of cheeses had low levels of volatiles stemming probably from the restricting effect of scalding or cooking that are employed in the manufacture of these cheeses and on the biochemical and/or microbial activity. Civil, Ezine, and Mihalic cheeses had somewhat different aroma profiles, but they were closely located near the cheeses including Dil, Urfa, Orgu, etc. The results suggest that each variety of cheese had different volatiles profile and that the manufacturing technique as well as ripening conditions of the cheeses played a major role on the individual volatile profiles.