Volatile compounds in Nanos cheese: their formation during ripening and sesonal variation

Abstract

The objective of this study was to evaluate the formation of volatile compounds (VCs) during ripening time in different seasons (summer, winter) of Nanos cheese with Protected Designation of Origin (PDO). The study was also undertaken to compare the aroma profile of feed and milk sampled in two different seasons from the protected area. The VCs analysis was performed by solid-phase micro extraction-gas chromatography–mass spectrometry. Altogether, 62 different VCs were detected throughout cheese ripening where their quantity varied with the time of ripening and season. In cheeses from winter season, there was a higher concentration of some fatty acids and esters. Besides, the evaluated differences of cheese samples by season indicated the transfers of some VCs from feed and/or milk into cheese. The most important possible links between cheese with feed and/or milk from different season were found in case of 9 VCs (acetic acid, butanoic acid, 3-methyl butanoic acid, hexanoic acid; ethyl ester of hexanoic acid, -octanoic acid, and -decanoic acid-; 2-butanone, pinane, sabinene) which also define the season. The changes in the amount of some VCs through ripening were significant (e.g. content of some fatty acids and esters increased while content of acetoin and diacetyl decreased). This is the first report which deals with the changes in cheese during ripening influenced by season and feeding system and the transfers of VCs from feed and milk to cheese in the case of traditional Nanos cheese, which was chosen as a model system for other hard type cheeses.