Sodium glutamate and glutamic acid decarboxylase as alternative for classical chemical leavening in wheat (pan)cake batter systems

Abstract

We investigated the use of sodium glutamate and glutamic acid decarboxylase (GAD) as alternative for classical chemical leavening systems (CCLS) in batter-derived bakery products. In the presence of its cofactor pyridoxal 5′-phosphate, GAD catalyses (sodium) glutamate conversion into carbon dioxide and γ-aminobutyric acid. Based on its high recombinant production yield in Escherichia coli and high in vitro specific activity, GAD from Streptococcus thermophilus was selected from a series of GADs for further research. The enzymatic leavening system (ELS) and CCLS were compared in terms of efficiency of carbon dioxide release in pancake batter at 50 °C. At this temperature, the ELS led to the highest leavening. In pancake baking, fast heating resulted in swift inactivation of the GAD, leading to reduced leavening. In cream cake baking, however, the slower heating rate allowed the ELS to exert its activity for a longer period under the conditions used, resulting in more leavening than with the CCLS. Sucrose affected the ELS neither in pancake batter nor in cake batter, but resulted in increased batter leavening due to the increased batter viscosity.