Measuring Cheese Maturation with the Fluorescence Fingerprint

Abstract

The objective of this research was to develop a method using the fluorescence fingerprint (FF) to measure cheese maturation. FFs of sixteen cheese samples with maturation periods of 7 to 329 days were measured with 8 replicates for each sample, along with reference values of proteolysis index (ratio of soluble to total nitrogen) and total free amino acids. A partial least-squares (PLS) model to predict the maturation time, proteolysis index and free amino acids from the FF data was constructed. The coefficient of determination for cross-validation (R²CV) was 0.93, 0.79, and 0.90 for the three indices, respectively. From the loadings of the PLS model, it was found that emission spectra at 345 nm excitation, attributable to oxidized lipids and Maillard reaction products, increased in intensity with prolonged maturation time.