Caracterização de farinhas cruas e extrusadas obtidas a partir de grão quebrados de diferentes genótipos de arroz.

• Main Author: BECKER, Fernanda Salamoni
• Publication Date: 2010
• Format: Master thesis
• Language: por
• Source: Repositório Institucional da UFG
• Download full: http://repositorio.bc.ufg.br/tede/handle/tde/1426
• topic: Orysa sativa L.; subproduto; extrusão.; 1. Orysa sativa 2. Subproduto 3. Extrusão; Oryza sativa L.; by product; extrusion.; CNPQ::CIENCIAS AGRARIAS::CIENCIA E TECNOLOGIA DE ALIMENTOS::TECNOLOGIA DE ALIMENTOS

The objective of this study was to characterize raw and pre-gelatinized flours obtained from broken grains of different genotypes of rice. Were used grains of rice cultivar IRGA 417, BRS Primavera and CNA 8502, vintage 2008. The raw and extruded flours were characterized physically as the expansion index (EI), color, texture, scanning electron microscopy (SRM), chemical composition, amylose content, water absorption and water solubility index (WAI / WSI) and milk (MAI/MSI), oil absorption index (OAI) and viscoamylographic properties. The cultivar IRGA 417 showed higher IE from the extrudates. The raw and extruded flours were differentiated to the parameters of color, browning, yellowing and reddening after extrusion. The raw and extruded rice flours from IRGA 417 and BRS Primavera and extruded CNA 8502 had a percentage higher than 90% of fine particles (˂ 250 microns). The SRM was observed in the presence of raw flours components intact or loose clusters, while in the extruded they presented themselves as a compact mass, amorphous. Extrusion had no effect on ash content and it was only the effect of genotype. The flours had its moisture content and lipid reduced after extrusion, while the protein content remained unchanged in IRGA 417 and CNA 8502, increasing in BRS Primavera. Extrusion increased the average amylose content in flour. The WAI, WSI, OAI, and MSI increased with the extrusion, and the MAL and MSL higher than those of WAI and WSI in raw and extruded flours of different genotypes. The initial viscosity of the raw flours was low, with high peak viscosity and subsequent drop in viscosity and high retrogradation. The flours extruded, low values of peak viscosity, final viscosity, breakdown viscosity and retrogradation were observed. Extrusion changed in physical properties in most chemical properties and technological characteristics of rice flour, varying, sometimes between genetic materials.