Method and apparatus for multi-stage stabilization of whole grain flour

A method of providing a whole-grain flour having reduced lipase enzyme activity using a two-stage deactivation process, the method comprising:

• separating a flour fraction having endosperm from a bran fraction having bran and germ, the bran fraction having a lipase enzyme activity;
• subjecting the bran fraction to a first deactivation step effective deactivate a first portion of the lipase enzyme activity;
• subjecting the bran fraction to a second deactivation step effective to deactivate a second portion of the enzymatic activity and to provide a treated bran fraction;
• and
• combining the treated bran fraction with the separated flour fraction to provide a whole-grain flour having reduced lipase enzyme activity, wherein the lipase enzyme activity in the treated bran fraction is reduced by about 77 to about 100 percent relative the lipase activity of the bran fraction.

A grain processing system configured to deactivate a lipase enzyme in a whole grain within a short amount of time, the system comprising:

• a hydration chamber arranged and configured to provide steam hydration effective to hydrate a milled bran fraction having both bran and germ and to deactivate at least a portion of a lipase enzyme activity in the bran fraction to form a hydrated bran fraction;
• a microwave chamber after the hydration chamber arranged and configured to dry the hydrated bran fraction and to further deactivate the lipase enzyme activity in the hydrated bran fraction;
• a breaking device positioned between the hydration chamber and the microwave chamber arranged and configured to break apart any agglomerates of the hydrated bran fraction that form in the hydration chamber;
• a conveyor connecting the hydration chamber to the microwave chamber;
• and
• the hydration chamber and microwave chamber configured to reduce the lipase enzyme activity by about 77 to about 100 percent relative the milled bran fraction in less than about 600 seconds.