The effect of chitosan solution pH on the degree of swelling was more significant when chitosan solution concentration was 0.7%(w/v) (Po0:0001) than when it was 1.0%(w/v) (Po0:005) (Table 1). With 1.5%( w/v ) xanthan concentration, the increases in pH had no significant effect on the SD (P40:05), whereas at other xanthan concentrations, the degree of swelling decreased significantly when chitosan pH was increased from 4.5 to 6.2. Such significant decreases in SD with increasing chitosan pH could be attributed to the changes in the chain flexibility of chitosan polymer with the changes in the solution pH .