Abstract:
Defatted rice bran (DRB) is composed of high nutritional values. However, the addition of DRB into food products is limited because of its rough and heterogeneous texture. The objective of this research was to reduce particle size of DRB by grinding and sieving through 100, 170, 200 and 400mesh. Results showed that grinding and particle size reduction significantly changed physic-chemical properties of DRB (p less than 0.05). Color parameters of DRB; L increased as the sieve number increased but a and b showed opposite results. The DRB which passed through 100 mesh had the lowest L but the highest a and b. Viscosity increased as the particle size decreased. The DRB passed through sieve number 200 mesh had the highest soluble dietary fiber and protein contents (8.68 + 1.08 and 25.03 + 1.45 percent) but the lowest insoluble dietary fiber contents (15.20 + 1.22 percent). For functional properties analysis, the DRB passed through sieve number 170 and 200 mesh had the minimum water holding capacity (WHC) values (0.45 + 0.04 and 0.47 + 0.02 g per g sample). The water retention capacity (WRC) significantly increased as sieve number decreased (particle size of DRB increased) (p less than 0.05). The WRC of DRB passed through sieves numbers 400, 200, 170 and 100 mesh were 2.96 + 0.04, 3.38 + 0.17, 3.60 + 0.10 and 4.93 + 0.05 g per g sample, respectively). The fat adsorption capacity (FAC) tended to decreased as the particles size of DRB decreased. The FAC of 150 um DRB which was passed through sieve number 100 was 4.15 + 0.06 g per g sample