Assessing the quality of dry sausages using fluorescence spectroscopy, physico-chemical, and dynamic testing...

The viscoelastic and the structure properties of three brands of dry sausages (Auvergne, Beef-poultry, and Galbanetto) were studied using dynamic rheology and fluorescence spectroscopy. The storage and the loss modulus of sausage samples showed a viscoelastic character. The principal component analysis carried out on the normalized rheological and physico-chemical parameters allowed to differentiate the sausage samples into three groups according to their brands. This trend was confirmed by the factorial discriminant analysis where 74.44% of correct classification was obtained. The emission spectra acquired after excitation set at 290, 340, and 360 nm and excitation spectra scanned after emission set at 410 nm allowed clear differentiation between the three brand samples. The obtained results were confirmed following the application of partial least squares regression to the fluorescence and physico-chemical parameters since an excellent prediction of moisture content was obtained from the excitation spectra set at 340 nm (R²  = 0.99) and 360 nm (R²  = 0.99). The protein content of dry sausages was well predicted after excitation set at 290 and 340 nm with R² of 0.96 and 0.97, respectively, while the fat level was well estimated after excitation set at 340 and 360 nm and emission set at 410 nm (R²  = 0.96, 0.96 and 0.94, respectively). The obtained results showed the potential use of fluorescence spectroscopy as a rapid technique for evaluating the quality of dry sausages.