The effect of concentration of sodium hydroxide on the gelatinization
of hypochlorite oxidized maize starches was thoroughly investigated. I
t was found that oxidation of starch increases its affinity towards ge
latinization with alkali solutions at room temperature. Clear gelatini
zed starch could be obtained immediately at a concentration of sodium
hydroxide of 1% on using hypochlorite oxidized starches irrespective o
f their degree of oxidation. While in case of native maize starch clea
r gelatinized paste was obtained at a concentration of 4% or more. The
rheological properties of the alkali gelatinized starches were determ
ined after 2 h of preparation and after storing of their pastes for 4
days. Hypochlorite oxidation of starch changes its rheological charact
eristics from non-Newtonian thixotropic to non-Newtonian pseudoplastic
. The suitability of one g/l active chlorine oxidized maize starches g
elatinized at 25 degrees C, under the influence of different concentra
tions of sodium hydroxide, either alone or in admixture with sodium al
ginate as thickeners in printing pastes of vat dyes was thoroughly inv
estigated.