Optical characterization of biological tissues provides advantages like the non-invasive or non-contact characters, or an increased image resolution. The use of the polarization information, apart from the intensity, leads to new data for a better diagnosis. In this work, we use the Group Theory applied to polarimetry to analyse the polarization behaviour of samples. The SU(4)-O+(6) homomorphism allows us to obtain the Mueller Coherency matrix from the Mueller matrix, and applying the target decomposition theorem, which provides information on tissue structure and separates different polarization effects by means mainly of the eigenvalues and eigenvectors, tissue imaging contrast can be increased. The analysis is applied to glucose suspensions of polystyrene spheres of different concentrations, whose behaviour can be modelled by means of single or multiple scattering depending on the concentration, either in the Rayleigh or Mie regimes. The results could be applied to cell cultures, where cancerous cells grow without control, or even to some anemia pathologies, where the number of erythrocytes in blood decreases.