By an addition of lipase in the preparation of flour dough, the dough decreased its hardness and elasticity, and the gluten prepared from this dough was remarkably extensible and soft. In chemical analysis of the gluten, it was proved that the ratio of lipid and protein was not influenced by the lipase addition, but the glutenin content in the treated gluten was distinctly smaller. As for the protein composition of the dough with lipase addition, the contents of 70% EtOH-soluble N, probably gliadin, and 5% K2SO4-soluble N were both, increased, while glutenin content was decreased.
It was suggested that a part of glutenin in gluten changed into gliadin by the addition of lipase in the dough.