European Journal of Nutrition & Food Safety

Aims: The main objective of the study was to optimise selected bread premix ingredients (sugar, salt, improver, softener) and dough proving temperature and to evaluate their effects on dough properties for premium bread production.

Study Design:  A combined optimal design (I-Optimal) was used.

Place and Duration of Study: The study was conducted at the Food Science Laboratory of the Rivers State University, Port Harcourt, Nigeria, between April 2025 and July 2026.

Methodology: Dough was prepared with wheat flour and premix (sugar, salt, improver, softener) at given design combinations and process conditions and characterised using the Chopin Mixolab instrument. Results obtained for the dependent variables were subjected to response surface analysis.

Results: RSM produced significant (p<0.05) fitted regression models for all four responses: dough specific volume, water absorption, dough development time and dough weakening, with coefficient of determination (R²) values of 79.72, 95.60, 86.83 and 94.23%, respectively. The corresponding coefficient of variation (CV) values were 2.61, 0.79, 5.63 and 2.14%, respectively. None of the model lack-of-fit tests was significant (p>0.05). The optimum mixture components of sugar, salt, improver and softener were 11.20, 1.40, 0.20 and 0.10%, respectively, while the optimum process factor of proving temperature was 37.92^oC, at a desirability index of 0.930.

Conclusion: No significant differences (p>0.05) were detected between the predicted and experimental measurements of dough specific volume, dough development time or dough weakening.