The variation was dependent on the chemical structure of the
hydrocolloids added. Among the four commercial hydrocolloids
tested, XG was most effective in reducing
syneresis, and reduction of retrogradation increased with
increasing concentrations of XG (0.50%40.25%). For the
other hydrocolloids, LBG was more effective in retarding
retrogradation than KGM but syneresis increased when
the addition was increased from 0.25% to 0.50%, whereas
addition of GG resulted in a negative effect by increasing
syneresis.
Analysis of retrogradation of starch gels as determined
by syneresis indicated that quick freezing rate retarded
starch retrogradation more than medium and slow freezing
rates (0.06, 0.09 and 2.30 1C/min, respectively).
Finally, the above results indicate that the best treatment
conditions for the reduction of starch retrogradation
was the addition of 0.50% XG with a freezing rate of
2.30 1C/min. Furthermore, it could retard changing of
texture in tapioca starch gel to a spongy structure during
repeated freeze–thawing.