•Less depolymerization of gluten was observed during dough processing of CSB.•SDS extractability of gluten decreased significantly during steaming of CSB.•Microstructure of gluten network was investigated by CLSM.•Glutenin depolymerization led to weakening of GMP gels in G′ and G″.•Gluteinin depolymerization negatively correlated with GMP quantity and subunits.Polymerization of gluten and the changes of glutenin macropolymer (GMP) during the production of Chinese steamed bread (CSB) were investigated, providing a theoretical basis to improve and regulate the quality of CSB. Protein extractability and free sulfhydryl (SH) contents increased to some degree during the dough preparation stage, but significantly (P < 0.05) decreased during steaming. Remarkable protein aggregates were observed in sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) patterns. The microstructure study of the gas cell and the protein network by confocal laser scanning microscopy (CLSM) further revealed the formation of a continuous and three-dimensional gluten network. The loss and recovery of GMP wet weight during dough processing were significant (P < 0.05). Glutenin depolymerization negatively correlated with GMP wet weight and the contents of high molecular weight glutenin subunits (HMW-GS) and low molecular weight glutenin subunits (LMW-GS). Gluten polymerization led to a decrease in G′ and G″ of GMP while gluten depolymerization induced a slight recovery in G′ and G″ of GMP.

•Oat protein isolate (OPI)–dextran (Dex) conjugates were produced by glycation reaction in an aqueous solution.•OPI–Dex conjugates formed emulsions exhibited better emulsifying properties under different homogenization pressures.•OPI–Dex conjugates stabilized emulsion maintained the well emulsion stability to environmental stresses.•CLSM depicted more uniform and smaller oil droplets for emulsions prepared with OPI–Dex conjugates.In order to improve the emulsifying properties of oat protein, oat protein isolate (OPI)–dextran (Dex) conjugates were prepared by glycation reaction. Emulsifying properties of emulsions stabilized by native OPI (OPIN), OPI–Dex conjugates (ODC) and heated OPI (OPIH) were characterized by zeta-potential, mean droplet size and microstructure. The results showed that the covalent attachment of OPI and dextran was confirmed by determining degree of graft and SDS–PAGE. OPI–Dex conjugates were capable of forming a finer emulsion, which exhibited smaller average particle size and better storage stability under different homogenization pressures (30, 60, 90 MPa) compared with OPIN and OPIH. When assessed in different pH and ionic strength, emulsions stabilized by OPI–Dex conjugates resulted in improved emulsion stability to environmental stresses. Confocal laser scanning microscopy depicted more uniform and smaller oil droplets that had a reduced tendency to coalesce for emulsions prepared with ODC.

•Artificial neural network exhibited good fitting ability in modeling the fermentation process.•A significant increase of total contents of MBQ and DMBQ was achieved.•A novel method was established to analyze two-factor interactions.Methoxy-ρ-benzoquinone (MBQ) and 2, 6-dimethoxy-ρ-benzoquinone (DMBQ) are two potential anticancer compounds in fermented wheat germ. In present study, modeling and optimization of added macronutrients, microelements, vitamins for producing MBQ and DMBQ was investigated using artificial neural network (ANN) combined with genetic algorithm (GA). A configuration of 16-11-1 ANN model with Levenberg-Marquardt training algorithm was applied for modeling the complicated nonlinear interactions among 16 nutrients in fermentation process. Under the guidance of optimized scheme, the total contents of MBQ and DMBQ was improved by 117% compared with that in the control group. Further, by evaluating the relative importance of each nutrient in terms of the two benzoquinones’ yield, macronutrients and microelements were found to have a greater influence than most of vitamins. It was also observed that a number of interactions between nutrients affected the yield of MBQ and DMBQ remarkably.