A calcium-induced pectin gel bead (PB) containing pectin hydrolysate and/or chitosan (CS) was prepared, after which the relationship between erosion of the PB and drug release from the PB in artificial gastrointestinal juice was investigated. The PB gradually disintegrated in gastric fluid, and the rate of erosion of the PB was changed by modification of the gel matrix. The amount of calcium ion used to make the PB had little effect on drug release; however, adding CS to the PB markedly suppressed drug release in intestinal fluid. (C) 2005 Wiley Periodicals, Inc.