Importance of free fatty acids in Parmesan cheese

The contribution of free fatty acids (FFAs) to Parmesan cheese aroma was evaluated using aroma extract dilution analysis (AEDA) and odor activity value (OAV) methodologies. FFAs with high flavor dilution (FD) values were isolated with an amino solid phase extraction column and quantified using gas chromatography. Both AEDA and OAV analyses suggest that acetic, butanoic, hexanoic, octanoic and decanoic acids are extremely important to the flavor of Parmesan cheese due to the very high FD and OAV values obtained. Butanoic acid is the most important as measured by OAV, both nasally and retronasally. These FFAs are the major contributors to the lipolyzed flavor of this type of cheese. Branched chain FFAs, such as 2-methylpropanoic and 3-methylbutanoic acids, were identified by AEDA but were not found to be important aroma compounds by this approach. FFAs levels in various brands of Parmesan cheeses are also reported in this paper.