Limit dextrinase (EC 3.2.1.41) partially purified from rice seeds was immobilized by adsorption on gamma-alumina beads. Binding and activity yields were 88 and 52%, respectively. The adsorbed enzyme showed a broader pH optimum and an increased thermal stability compared to the free one. Optimum temperature was between 50 and 60 degrees C and the enzyme retained about 70% of the initial activity after 7 days of incubation at 40 degrees C in the presence of Ca2+. The immobilized biocatalyst degraded pullulan completely to maltotriose and effectively converted both acid hydrolysed amylodextrins and beta-limit dextrins into maltose and maltotriose. The possibility of using a debranching enzyme of plant origin in starch processing can be considered to be a new approach for the improvement of the quality of sugar syrups used in the food industry.