Freezing dough is well known to be detrimental to the quality of the final bread, with water disassociating itself from protein and starch and forming ice crystals. Various ingredients or specialty flours have been employed to reduce these effects, but soy proteins show significant potential because they have good water binding properties.
New data published in the Journal of Cereal Science indicated that soy protein is indeed suitable for inclusion in frozen dough formulations, with 70% of participants in a sensory panel rating the soy bread “moderately acceptable” or higher.
Amber Simmons and her co-workers from Ohio State University write: “The soy dough formulation presented here appeared to be at least as amenable to frozen storage as the wheat counterpart, with soy addition showing marked physical improvements during frozen storage in the realm of extensibility, resistive force to extension, and hardness of the baked loaf.”
Formulations details
The Columbus, OH-based scientists formulated bread with 48.5% soy ingredients, including defatted soy flour (Archer Daniels Mills) and soy milk powder (Devansoy, Inc.), and stored it at −20 °C for 4 weeks. The sensory attributes of the product were compared with bread baked from fresh dough.
Results showed that, compared with the wheat bread, the soy bread was denser, chewier, and had a higher moisture content.
Bread baked from both fresh and frozen dough, 70% of the panelists rated it “moderately acceptable” or higher.
“Hydrocolloids and emulsifiers were not used in this formulation in order to focus on the changes imparted by soy addition alone, however they may improve the frozen shelf life of the soy dough in addition to increasing extensibility and loaf volume,” wrote Simmons and her co-authors.
“The effects of additives on soy dough remain to be explored.”