Profiling aged artisanal cheddar cheese using secondary electrospray ionization mass spectrometry.

A number of direct injection mass spectrometry methods that can sample foods nondestructively and without sample preparation are being developed with applications ranging from the rapid assessment of food safety to the verification of protected designations of origin. In this pilot study, secondary electrospray ionization mass spectrometry (SESI-MS) in positive- and negative-ion modes was used to collect volatile fingerprints of artisanal Cheddar cheeses aged for one to three years. SESI-MS fingerprints were found to change in an aging-dependent manner and can be used to descriptively and predictively categorize Cheddars by their aging period, identify volatile components that increase or decrease with aging, and robustly discriminate individual batches of artisanal cheese. From these results, it was concluded that SESI-MS volatile fingerprinting could be used by artisanal food producers to characterize their products during production and aging, providing useful data to help them maximize the value of each batch.