Abstract:ObjectiveThis study aimed to decipher the mechanism through which wheat flour components influenced the deterioration of frozen streamed bread after re-steaming. Method The composite wheat flour samples with different formulations were used to prepare steamed bread, which was then frozen. The specific volume, texture, glutenin macropolymer (GMP) mass, free sulfhydryl molality, and relative molecular mass of proteins were measured after re-steaming of frozen steamed bread. Result The protein mass fraction in the composite wheat flour significantly influenced the thermomechanical properties of dough and the frozen storage stability of steamed bread. The MF1 formulation, with higher protein mass fraction, produced dough with greater water absorption, development time, and stability. Its gluten network structure is more intact, exhibited higher GMP mass and lower mass fraction of SDS-extractable proteins, which better preserved the specific volume and textural properties of steamed bread during frozen storage. As the frozen storage time prolonged, the gluten network underwent significant depolymerization, as manifested by the decreases of 1.67%~15.12% in GMP mass, increases of 2.44%~37.68% in free sulfhydryl molality, and increases of 9.56%~48.84% in mass fraction of SDS-extractable proteins. Correspondingly, the streamed breed exhibited decreased specific volume, deteriorated texture, and uneven pore distribution. Pearson correlation analysis revealed the intrinsic relationships between macroscopic quality indicators, protein structural parameters, and dough rheological properties at different frozen storage stages. Conclusion The deterioration of frozen steamed bread after re-steaming is related to the differences in wheat flour components. In the composite wheat flour systems used, gluten protein mass fraction and complete GMP structure are significantly associated with textural properties of frozen steamed bread after re-steaming. Maintaining the integrity of the gluten network structure plays an important role in slowing down the quality deterioration of frozen streamed bread after re-steaming. This study provides a theoretical basis for improving frozen wheat flour-based products.
