Use of front face fluorescence spectroscopy coupled with multivariate data analysis for monitoring biscuits' quality during aging

In this study, the potentiality of front face fluorescence spectroscopy (FFFS) for the evaluation of the quality of biscuits manufactured with butylated hydroxytoluene and pomegranate peel extract during aging was investigated. By using the principal component analysis, vitamin A and tryptophan spectra allowed a clear discrimination between biscuit samples according to the nature of antioxidants, while fluorescent Maillard reaction products spectra showed clear differentiation between samples according to the storage time. Clear differentiation between biscuits according to the used antioxidants and storage time was achieved by using common components and specific weights analysis. Using partial least‐squares regression, excellent prediction of water activity (R (2) = 0.95), and L* values (R (2) = 0.92), and approximate prediction of hardness (R (2) = 0.78), b* values (R (2) = 0.74), and moisture content (R (2) = 0.74) were shown. However, the FFFS failed to predict a* values, primary and secondary oxidation products (R (2) < 0.6).