1981 Volume 28 Issue 8 Pages 444-450
In order to elucidate the cooking characteristics of gelatinized rice, experiments measuring its physical properties and sensory evaluations were conducted using both non-glutinous and glutinous rice. The non-glutinous rice was gelatinized up to 79.2% and the glutinous rice to 95.8%. Amylography of rice powder showed: Gelatinized non-glutionous rice increased its viscosity slowly from about 65°C and no 'breakdown' was observed. However, the highly gelatinized glutinous rice reached the maximum viscosity immediately after the measurement was started. This is considered a very unique amylogram. The textural properties of cooked rice were as follows: Both glutinous and non-glutinous rice in a gelatinized state were harder and more cohesive than polished rice. Glutinous rice was stickier than non-glutinous rice, however, both gelatinized types were less sticky than polished rice. The 'creep curve' of the cooked rice was obtained with a creepmeter to analyze the static viscoelasticity. Every sample could be explained according to the six element models of Hookean body, two pairs of Voigt body, and Newtonean body. The elastic modulus were 105 to 106 dyn/cmcm2, and the coefficients of viscosity were 107 to 1010 poise. The hedonic scale values in sensory evaluation of cooked rice were closely related to their physical properties. However, the appearance of gelatinized rice was slightly inferior to polished rice.
