LAUSR

Abstract The effect of soy protein isolate (SPI) and dietary fibers [maize bran (MB), resistant maltodextrin (RMD)] on cooked extruded rice quality-related parameters and relating rheology to the human gastric emptying measurement of Lag phase were investigated. DSC onset temperature (To) and peak temperature (Tp) of extruded rice substituted with 20 % SPI (20SPI-ER) were higher than of extruded rice substituted with 20 % MB (20MB-ER) and substituted with 20 % RMD (20RMD-ER). Peak viscosity of 20SPI-ER was lower than that of 20MB-ER and 20RMD-ER, indicating that SPI delayed starch gelatinization. Hardness and stickiness values of cooked 20SPI-ER were significantly higher than those of the control, 20MB-ER, and 20RMD-ER. Storage modulus (G′) value of cooked 20SPI-ER was also higher than the control. It is possible that the swelling of starch granules was decreased when 20%SPI was supplemented. For human gastric emptying, cooked 20SPI-ER resulted in the highest lag phase, indicating that the time of grinding and mixing in the stomach took longer for this reformed rice. Overall the soy-containing cooked extruded rices were somewhat harder than the fiber-containing rices, which may not be as appealing to consumers, though they had a slightly longer Lag phase in the stomach which could relate feeling of fullness.