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In this paper, the fine bran processed by heating and pressuring was added into the flour for the steamed bread. The moisture, TPA, water distribution and so on of steamed bread was evaluated during the storage in cool. The results showed that there was a certain correlation between the dosage of the fine bran and the water absorption of the flour, the regression equation is y=32.525*x+44.207, R2=0.996 9. The additive of the fine bran led to an increase of water content of steamed bread. The water migration of the steam bread weakened in cold storage, with the strong and weak binding water of steamed bread increased.The hardness and adhesion of the steamed bread strengthened, the reactivity and adhesion decreased for the addition of fine bran. Moreover, the yield value of steamed bread increased with the increase of bran content.

Summary: The effects of microwave heating (MW), steaming (SM), boiling (BL) and baking (BK) on the structure and functional properties of quinoa protein isolates (QPI) were investigated. SDS‐PAGE showed the 20–30 kDa band strength of QPI‐BL was enhanced, which indicated the disulphide bond was broken and protein molecules dissociated. Due to the recombination of subunits, some large molecular weight or insoluble polymer components of QPI‐SM and QPI‐BK did not pass through the gel. Microwave heating and boiling showed negative effects for α‐helix and positive effects for β‐sheet, which implied the molecular structure was transformed from ordered to disordered, the secondary structure became loose. The reduction of free SH (sulfhydryl) and surface hydrophobicity implied that aggregation and cross‐linking of protein molecules for QPI‐SM and QPI‐BK. QPI, QPI‐MW and QPI‐BL exhibited better solubility, which was related to the water holding capacity (WHC) and emulsification. For QPI‐SM and QPI‐BK, functional properties (including solubility, WHC and gel‐forming ability) decreased due to molecular aggregation. Heat treatments significantly affect the structure and functional properties of QPI, the current research showed that microwave heating and boiling might be better heat treatment methods for QPI and would help the development of quinoa protein products. [ABSTRACT FROM AUTHOR]