Physical characteristics of rice flours pregelatinized by different heating methods as a raw material for instant rice gruel were investigated. Rice was gelatinized by steaming, drum drying, extrusion, and roasting. After gelatinization, rice was ground, packaged and stored at 4 until analyzed. The pH of the steamed was the lowest; pH 4.5 and the last of them were similar, from 5.8 in the drum dried to 6.4 in the extruded. Color of the flours were very similar except for the roasted and also in the suspensions of the flours the roasted has very high value in yellowness, b value and in redness, a value, was different from the others. The XRD (X-ray diffraction) patterns of all pregelatinized rice flours were very similar and characterized by the typical cereal "A" type. In apparent viscosity of the flours at 90% moisture content, the drum dried was the highest, extremely high, the second the extruded and the roasted the lowest with not much difference in the steamed. With increasing temperatures, the viscosity was decreased. For instant rice gruel application, further studies in sensory properties of these pregelatinized rice flours are needed.
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