The affinity of pitch components for carboxylated dextran (CD) surfaces is studied by optical microscopy and surface plasmon resonance (SPR). CD is used as a model of the cellulose structure of pulp fibres. The dynamics of adsorption and desorption are followed in real time by SPR. The parameters investigated are temperature and pitch concentration. Particle size and shape are found to be strongly related to the pitch components in the extract and parametric considerations in the preparation process. Pitch components exhibit a very low affinity for CD at 20°C However this affinity increases as the CD surface is modified by deposited pitch components themselves. The affinity of pitch components for CD and especially for themselves drastically increases with temperature.