Use of Fluorescence Spectroscopy Combined with Chemometric Tools for the Quality Assessment of Fermented Parkia Biglobosa Seeds During Storage

Fermented <i>Parkia biglobosa</i> seed is a food of high nutritional value that plays a vital role in the diet of many populations, particularly in West Africa. This food offers a combination of proteins, vitamins, minerals and fibers, while having beneficial properties for the health of consumers. Thus, this study aimed to investigate the feasibility of using front face fluorescence (FFFS) to assess the quality of dry fermented seed of <i>Parkia biglobosa (Soumbara)</i> during storage. In this study, the physicochemical parameters (pH, fat and peroxide value (PV)) were determined. The obtained results showed that the pH, fat and PV values varied with the storage duration. For example, from day 1 to day 30, the pH values increased from 6.130 ± 0.05 to 6.723 ± 0.07. By applying principal component analysis (PCA) and factorial discriminant analysis (FDA) on the emission spectra acquired after excitation wavelengths fixed at 250 nm, 340 nm, 360 nm, 290, 290 nm and 410 nm, a perfect discrimination of the soumbara samples according to the storage times. In addition, the factorial discriminant analysis allowed to obtain a correct classification rate between 90 and 100. Regarding the prediction of the pH, fat and PV level, the partial least squares regression (PLSR) applied to the FFFS spectra data gave an excellent prediction with R<sup>2</sup> values of 0.99. The results obtained in this study show that the FFFS method coupled with descriptive and predictive chemometric tools could be applied as an effective, rapid and non-destructive method for monitoring the quality of fermented <i>Parkia biglobosa</i> (soumbara) seeds during storage.