Products development from wheat-rice composite flour

Wheatless bread could be produced from rice flour using 2.5 to 3.0 percent of hydroxypropyl methylcellulose. Rice bread crumb made from low amylose rice flour with amylose content of 16.4 percent was comparatively found denser, softer and more sticky with crack along the top surface and having sandy crust. Bread made of medium amylose rice four had crumbly and rough texture with porous crust on the top. Different flour milling methods had influence on rice bread aroma. Pregelatinized flours for improving gas retention capacity during fermentation and baking stage were developed by extrusion cooking. The modified jasmine rice flour and medium amylose flour had higher cold viscosity than the raw rice flours. The viscosity of PD-KDML and PW-E flours were 22 and 79 RVR. Substitution of modified rice flour showed similar volume to those of wheat at level 10-20 percent and decrease at comparatively lower rate after 30 percent. Physical and organoleptic quality of unmodified rice flour substitution bread showed slow decrease at 10-20 percent substitution and at higher decreasing rate after 30 percent substitution. Physical and organoleptic quality of modified rice flour substitution bread showed slightly decrease in score up to 30 percent substitution. Crumb firmness of unmodified rice flour substitution breads was dramatically increased at every level of substitution. Modified rice flour substitution bread showed the same trend but at much lower force used which indicated substantially softer texture or lower staling rate. Substitution of modified rice flour at level up to 30 percent showed no difference in consumer perception but could be detected by measuring instrument. At level of substitution over 40 percent, consumer could detect difference in taste and texture but in the range that they could still be accepted. The highest substitution at 70 percent was possible in making certain types of bread which require rather hard and crisp texture such as salt stick, pizza and pie crust.