Effect of Processing Paddy on Digestibility of Rice Starch by In vitro studies

Paddy (Oryza sativa L) (variety ‘IR – 64’), was
parboiled, puffed by sand roasting and fl aked by edge runner
and roller fl aker and variations in physical and physicochemical
properties were studied. Moisture contents were
lower (5.8–10.8%) in processed rice products compared
to raw materials (11.8%). Ratio of rice to sand in the case
of puffed rice preparation was optimized. The equilibrium
moisture content was 27.4% in raw rice while it was much
higher (38.9–81.0%) in processed rice. Sedimentation volume
was lowest (6.2 ml) in raw rice and highest (18.8 ml) in
popped rice. Starch content was 84.8 and 76.5–83% in raw
and processed rice, respectively. In vitro starch digestibility
was highest in roller fl aker fl akes and lowest in raw milled
rice. Among the ready to eat products, popped rice showed
least starch digestibility (~30%).