Gelling Behavior of Rice Flour Dispersions at Different Concentrations of Solids and Time of Heating

Rice flour dispersions, under suitable conditions of processing, can form
a gel. The effect of concentration of solids (10–18%) and time (0–75 min) of
processing on textural attributes, and viscoelasticity were investigated along
with sensory attributes. The textural attribute determined is gel strength, while
viscoelasticity was determined in terms of mechanical spectra like storage
modulus (G�), loss modulus (G�), complex viscosity (h*) and loss factor (tan
d) during a frequency sweep varying from 0.01 to 40 Hz at a constant stress of
25 Pa. Microstructural observation indicates the swelling of starch granules
in the beginning of heating, while damaged granule and leached-out materials
are visible at the end of the gelling process. Desirability function analysis has
been applied to obtain a rice gel with acceptable textural attributes; a solid
concentration of 15.2% and a heating time of 75 min can lead to the development
of a gel with a satisfaction level of 0.6.