Abstract:

This study examined the individual effects of four food additives on the quality of frozen dough steamed bread
made with a mixed culture consisting of yeast and rice wine containing the starter strains at a mass ratio of 4:5. The
proportions of the four additives when used in combination were optimized by response surface methodology. Experiments
were designed using combination of single factor method and Box-Behnken design. As a result, a mathematical model was
established describing the effect of the four food additives on the overall quality score of steamed bread and their optimal
levels were obtained. The quality of steamed bread was affected in decreasing order by xylanase, sodium polyacrylate,
diacetyl tartaric acid ester of mono(di)glycerides (DATEM) and trehalose, and their optimum combined proportions were
0.15% DATEM, 0.05% sodium polyacrylate, 25.73 mg/kg xylanase, and 3.65% trehalose. Under these conditions, the
expected sensory score of steamed bread was 84.646, and the actual value was 84 ± 0.74. The rheological properties of
frozen dough such as elastic modulus (G’) and viscous modulus (G”) were improved when the compound food additives
were added. This study has indicated that compound food additives can inhibit the formation of ice crystallization and
prevent the dough from recrystallization, reduce the damage to the mixed starter and the structure of the gluten network from
ice crystallization, and improve the qualities of dough and steamed bread.

Key words: frozen dough, steamed bread, food additive, response surface analysis