Physicochemical properties and textile utilization of low- and moderate-substituted carboxymethyl rice starches with various amylose content

The effects of low and moderate levels of degree of substitution (LDS similar to 0.2 and MDS similar to 0.6) on physico-chemical and textile printing properties of carboxymethyl rice starches (CMRS) containing different amylose (AM) content were investigated. With a similar level of AM, MDS CMRS displayed higher cold water solubility (CWS), yield stresses, and apparent viscosities than those of LDS CMRS. Furthermore, they were superior to LDS CMRS when used as textile print paste. AM also influenced the properties of CMRS with similar DS. When AM increased, CWS of LDS CMRS increased. However, yield stresses and apparent viscosities of CMRS decreased with increased AM. MDS waxy CMRS print paste provided the least color strength among other MDS CMRS. Nonetheless, DS was shown to have a far greater effect than AM on determination of CMRS properties. (C) 2010 Elsevier Ltd. All rights reserved.