| Resumo: |
Broken rice was used for the production of dry-milled flour by grinding on Pin Mill. Particle sizes distribution of the resulting flour shown that major portion was coarse flour. Physicochemical properties of the flour with differing particle sizes were investigated and utilized as raw material in rice noodle production; Sen Yai and Sen Mee. The protein content decreased whereas the ash content increased with decreasing particle size. The amylose content of each fraction was similar. Water absorption index (WAI) and water solubility index (WSI) were greater for fine flour. Fine flour also possessed high value of lightness (L*) and low yellowness (b*). Rapid visco analysis indicated that fine flour had lower gelatinization temperature while higher peak viscosity, breakdown and final viscosity than coarse flour. Thxtural characteristics of Sen Yai prepared from dry-milled rice flour were affected by particle sizes, flour slurry concentration, flour soaking and steaming time. Good qualities of Sen Yai were obtained from the finest flour (<200 mesh) with 33 % flour concentration, 3 hrs soaking and 5 min steaming. Increasing in soaking time and steaming time improved the noodle qualities. A process for production of Sen Mee from dry-milled rice flour comprised a) mixing rice flour with 35-40 % pregelatinise flour, added some water then kneaded to obtain a dough b) extruding the dough to form the noodle c) steaming the noodles d) drying the noodle at 45-48°C to a moisture content below 12 % by weight. Noodle quality was examined by cooking yield, cooking loss, tensile strength, break distance, hardness and stickiness. The results indicated that Sen Mee prepared from dry-milled rice flour gave rougher texture and easier to break up on cooking than the ones in the market.
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