During bread baking gliadin and glutenin form large gluten protein aggregates. In the baking phase glutenin becomes almost unextractable. Oxidizing agents (potassium iodate and bromate) increase both alpha- and gamma-gliadin extractability during baking, while a reducing agent (glutathione) decreases the levels of extractable alpha- and gamma-gliadins. It is concluded that during baking, gluten polymerizes through a sulfhydryl-disulfide exchange mechanism. Oxidizing agents hinder gliadin-glutenin linking during baking by reducing the level of free sulfhydryl groups, while addition of glutathione increases the level of gliadin to glutenin covalent binding. These findings demonstrate that redox agents exert an effect during baking with a possible impact on final product quality.
展开▼
