Rapid measurement of sardine freshness by using visible and near infrared spectroscopy

Freshness is an important attribute of sardine quality, which measurement for control purposes needs simple and rapid methods. This study shows the suitability of PCA of the averaged sardine VISNIR spectra to predict sardine freshness. The sample was composed of a relatively small number of sardines, the proposed method being suitable for routine analysis. The results of PLS tests indicated this method can be useful to confirm a sardine freshness class defined according to PCA results. The tests with PLS-DA and clustering indicated the practical interest of these last methods is lower, even though being in good agreement with those from PCA and PLS.