Disclosed are methods of processing raw leguminous materials, such as pea flour, pea concentrate, or pea isolate, to reduce non-volatile flavor components and in particular bound saponin compounds. The methods includes select processing steps by steam cooking a raw slurry to form a cooked slurry and drying the cooked slurry to form a processed material. An amount of non-volatile flavor components in the processed material is less than an amount of non-volatile flavor components in the raw materials.