VISCOELASTIC CHARACTERISTICS OF PART-BAKED BREAD UNDER DIFFERENT PROCESS CONDITIONS
Rheological studies in food have shown chemical changes during their preparation process. In bread making, dough viscoelasticity studies reflect the chemical changes produced by the baking process, which in turn modifies bread volume. The aim of this research was to study the effect of the freezing rate, part-baking and storage time on the viscoelastic properties and specific volume of part-baked bread and the specific volume of bread completely baked. We prepared water-flour dough for
... dough for viscoelastic evaluations. Formulated dough for part-baked bread was baked for 0, 3 or 6 min, frozen at two freezing rates: slow (0.15°C/min) or fast (1.45°C/min) and stored for 56 days. Every 14 days, par-baked bread frozen samples were thawed for rheological evaluations including: elastic moduli (G´), viscous moduli (G¨) and Tan δ. Another part of the thawed samples was re-baked (complete baked) to complete 10 min and the specific volume of bread was measured. We used a 3x2x5 factorial design experiment. An analysis of variance was carried out with 95% confidence level. The elastic moduli (G') increased with part-baking time. Part-baking time decreased Tan δ, increasing the elasticity in dough and part-baked bread. Part-baking time decreased gelatinization temperature peak in all frozen storage time. A longer storage time resulted in an increase in the elasticity of dough and part-baked bread. The specific volume of bread increased with part-baking time, however, this parameter decreased with storage time.