Effect of Freezing Rate and Storage Time on Gluten Protein Solubility, and Dough and Bread Properties

The aim of this study was to evaluate the effect of the freezing rate and storage time on the solubility of gluten proteins and on the fermentative and rheological properties of dough as well as the bread quality. Increased storage time very significantly decreased (P < 0.01) the quality of the dough and the bread. Dough frozen at a slow freezing rate exhibited a very significant decrease in the proportion of insoluble polymeric protein (IPP), an increase the protein solubility, a decrease the resistance to extension, an increase the viscous modulus (G′) and the gas retention decreased. In contrast, dough frozen at a fast freezing rate displayed a very significant decrease (P < 0.01) in the specific volume of the bread and a very significant increase (P < 0.01) in its hardness and a decrease in springiness. A higher content of IPP decreased the retention of CO2, and bread was harder and less springy. In conclusion, a slow freezing rate and a short storage period provide better quality bread. Practical Applications The quality of bakery products depends on the viscoelastic properties of the gluten proteins. In frozen dough, the gluten proteins are modified by the migration of water to form ice crystals. The size and shape of the crystals determine the changes in the proteins. Assessing the effect of the freezing rate and the storage period of bread dough on the changes in these proteins may facilitate improving the characteristics of frozen dough and bread. The information obtained from this work showed that the frozen storage is the most important factor that affects the dough and bread quality, and slow freezing rate is better to preserve the overall quality of frozen dough and bread. It could help bread makers to improve the quality of bread after thawing by using flours with protein quality with the features necessary for frozen dough and to obtain bread with better properties.