Patent GB-1285815-A (GB)
Title: Improvements in milling of cereal grains and processing of products derived therefrom
Inventor: WAYNE TRUMAN BENJAMIN
IPC: A23L7/10
Filed: 1970-04-22
Abstract: 1285815 Reducing cereal grains and processing the products T B WAYNE 22 April 1970 [7 May 1969] 19265/70 Heading A2Q In a process for the milling of cereal grains, e.g. wheat, maize, rye or sorghum, and processing of the products derived from the milling, wherein the milling and processing is carried out in the presence of a substantially nonaqueous extractive solvent, e.g. n-hexane, n-heptane, ethanol, isopropanol, acetone, ethyl ether, isopropyl ether, chlorinated ethers, ethylene dichloride trichloroethylene, or mixtures thereof, and wherein the fibrous, proteinaceous and starch components of the grain are separated in a final separation stage, the major portion of fibrous component is separated from the other components following the primary milling but in advance of the final separation stage, the separated portion of the fibrous component is recovered, the unseparated components are conducted to the final separation stage to separate them into the respective starch components, protein components, and the minor portion of the fibrous component, and the separated components are then separately recovered. As shown, a pipe 11 supplies a clarified, strong miscella containing the solvent to the grain inlet 10 of a milling machine M and also to wet milling section M1 of the machine, while a second pipe 11a feeds a weaker miscella to a rinse or wash section M2 of the machine. Crushed grain which is principally endosperm is delivered from outlet section M3 of the machine via outlet 14, while strong and weaker oil-containing miscella containing mainly bran coat and oily germ fractions delivered from outlets 11b and 12, respectively, and pass to extraction section E, either directly in the case of the strong miscella or via a storage tank 13 and pump 21 in the case of the weaker miscella. The solids extracted from these miscella pass via outlet 34 to a vibratory screen 36 and thence direct via outlet 39 to a delivery conveyer 40 for the fibrous component, thus by-passing sections B and D which deal principally with the separation and extraction of the crushed grain from outlet 14 of the milling machine. Alternatively, as indicated by the dotted line 34A, outlet 34 may be connected to separation stage B for the crushed grain, since the solids separated in the section B and a following section C are also arranged to be principally the fibrous component, as determined by the mesh chosen for vibratory screens 18, 25 and 43, so that the fibrous component ultimately passes via outlet 46 to the delivery conveyer 40. With the latter arrangement, the vibratory screen 36 would be omitted. The section B comprises a conveyer 15, the screens 18, 25, an intermediate attrition mill 24 and a conveyer 33 connecting the solids outlet of the screen 25 to a second attrition mill 42 followed by the screen 43, the last two components together with the screen 36, if provided, constituting the section C which, in either of the arrangements, handles both the crushed grain component originating at outlet 14 and the extracted solids component originating at outlet 34. Weak miscella is obtained from conveyer 15 and screen 18 and is fed via lines 16 and 20 to the tank 13, while a slurry containing miscella and fine solids is obtained from the screens 25 and 43 and passes via lines 28 and 47 to a tank 31 from which it passes via attrition mill 49 to the final separation section D. Where, as shown, the screen 36 is provided, the slurry obtained from this is mixed with the crushed grain component delivered by the conveyer 33 to the mill 42. The final separation stage consists of further screens and also centrifuges which separate out the remaining minor fraction of the fibrous component to the conveyer 42 and in addition separately deals with the proteinaceous and starch components which are delivered to outlets 54, 57. These outlets and the outlet from the conveyer 40 lead to separate desolventizer systems 55, 58 and 52, respectively, from which the final products, viz. protein, starch and fibre are obtained.