The functional effectiveness of reprocessed rice bran as an ingredient in bakery products.

Abstract

Rice bran, as a coproduct of the rice milling industry, is yet to be efficiently utilized for human consumption. Despite its excellent nutrition, its hypoallergenicity and recently claimed nutraceutical properties, it is mainly utilized for animal feed or simply discharged. It is of interest to incorporate this healthy ingredient back into our diet. In these studies, rice bran was processed by drum-drying and pin-milling. This processing step increased hydration capacity and removed grittiness by decreasing mean particle size from 444 to 72 microns and producing a desirable monomodal size distribution. There are no reported studies addressing differences in rice bran composition in food applications and specifically their effect on bread quality. Thus, we were interested in examining the functional properties of bread made with processed full-fat (FFRB) and defatted (DFRB) bran from three cultivars (long, medium and short grain rice) and to compare them to a control. For 10% and 20% replacements of wheat flour, respectively, loaf volume increased 2% for FFRB and decreased 6% for DFRB and decreased by 6% for FFRB and 17% for DFRB. Loaf volume was highest with medium rice bran and this was attributed to its lowest fiber content and highest starch content among three varieties. Texture profile analysis showed no significant differences as far as cohesiveness and springiness, but bread hardness, gumminess and chewiness increased with increased levels of rice bran and was higher for DFRB bread than for FFRB. Measurements of texture determined that there was no detrimental effect in adding 10% FFRB to the bread and a very slight hardening of the loaves with the 20% FFRB, when compared to the control. It was found that FFRB gave better textural characteristics than DFRB overall and differences amongst different rice bran varieties were not significant.