A process for obtaining a starch and a protein or both from grain flour,
the process steps comprising: providing grain flour; mixing the grain
flour with processed or fresh water to form a slurry; separating the
slurry into it at least two fractions, the at least two fractions
including two or more of a heavy A-starch fraction, a protein and
B-starch fraction, and a pentosan fraction; and generating a biogas from
at least one of the fractions from the separating step, the biogas being
used for generating energy.