Today in 1969, US Patent 3443958 A was issued, an invention of George E. Dennis, Richard C. Quittenton, and Kenneth R. Robinson, assigned to John Labatt Ltd., for their “Method of Preparing Ground Cereal Grains in the Production of Brewery Mash.” There’s no Abstract, but the invention is described as a “process for producing brewers wort in which cereal grains are dehulled, the dehulled grain is ground to form a fine grist and at least part of the hulls removed before grinding are recombined with the ground dehulled grain and passed through the mashing stage in the usual manner.” Here’s why they think their method is better.
According to this invention it has been determined that the above difficulties [milling problems] can be overcome by removing the hull from the grain before the milling operation. With the hulls removed the kernels of grain can now be more finely ground than was possible in the past and then the finely ground kernels can be recombined with the hulls at any point before the lautering stage. The result of this is an increased yield without any significant sacrifice in run-off time. A series of pilot plant tests indicated that an average yield increase of up to 2% could be obtained with a less than a 15% increase in lautering time.
The degree to which the kernels can be more finely ground according to this invention will be entirely dependent upon the particular situation. Thus, the actual particle size will be dependent upon the nature of the grain, the balance of the lautering time against yield permissible in a given situation, etc.