The possibility of identifying aqueous suspensions of protein-vitamin concentrates (paprin and gaprin) from the measurements of the light scattering matrix has been studied. Based on the real part of the refractive index determined by laser phase microscopy for paprin and gaprin, the scattering matrices of their dispersions in water were modelled. A theoretical analysis of the angular variations of the scattering-matrix elements has shown that the most reliable identification can be practically implemented in the spectral region, where the absorption of light by dispersed particles of at least one of the compared suspensions is small.