Electrical resistance oven baking as a tool to study crumb structure formation in gluten-free bread

Gradientless baking by means of ohmic heating was used for the first time in gluten-free (GF) bread making. Combination thereof with in-line measurements of batter height, viscosity and carbon dioxide (CO2) release proved to be powerful for studying structure formation in GF breads. GF breads studied here were based on (i) a mixture of potato and cassava starches and egg white powder (C/P-S+EW), (ii) rice flour (RF) or (iii) a mixture of RF and egg white powder (RF +EW). The work revealed that bread volume and crumb structure rely heavily on the balance between the moment of CO2 release from batter during baking and that of crumb setting. At the moment of CO2 release, C/P-S + EW bread crumb had already (partly) set, while this was not the case for RF bread crumb, resulting in a collapse and thus low volume of the latter. When a part of RF was replaced by egg white powder, the moment of CO2 release was postponed and the batter collapse was less pronounced, leading to a higher volume and a finer crumb. The presence of egg white proteins in C/P-S + EW or RF + EW batters improved gas cell stabilization. Thus, increasing batter stability or altering the moment of crumb setting results in GF breads with higher volume and a finer crumb structure.