The Effect of Carboxymethyl Cellulose Sodium on the Proofing Tolerance and Quality of Frozen Dough Steamed Bread

This study investigated the effects of dough proofing degree (1.1, 1.3, 1.5, and 1.7 mL/g) and carboxymethyl cellulose sodium (CMC-Na) on the quality of frozen dough steamed bread (FDSB). As the dough proofing degree was increased from 1.1 to 1.7 mL/g, the specific volume of FDSB initially increased and then decreased, with the maximum at 1.3 mL/g, and then dramatically decreased at 1.5 and 1.7 mL/g, accompanied by a harder texture and secession of crust and crumb, which were the detrimental effects brought by over-proofing. The optimal amount of CMC-Na effectively alleviated the deterioration associated with over-proofing, and the proofing tolerance of FDSB was increased from 1.3 mL/g to 1.7 mL/g. Fermentation analysis showed that CMC-Na significantly improved the extensibility and gas-holding capacity of the dough by increasing the maximum height of the dough (Hm) and the emergence time (T1) of Hm. Frequency sweep tests indicated that CMC-Na improved the plasticity of proofed dough by increasing loss factor tan δ. Significant reductions were found in peak viscosity and complex modulus G* in pasting properties tests and temperature sweep measurements, respectively, suggesting that CMC-Na influenced starch gelatinization and dough stiffening during steaming, which promoted the extension of the network structure, thus facilitating gas expansion and diffusion. These property changes theoretically explained the improvement in the proofing tolerance of FDSB by CMC-Na.