Patent GB-990063-A (GB)
Title: Process and apparatus for preparing rice products and rice products of said process
Inventor: GOROZPE RAUL DONDE
IPC: A23L7/196
Filed: 1962-01-24
Abstract: 990,063. Quick-cooking rice. CORN PRODUCTS CO. Jan. 24, 1962, No. 2593/62. Headings A2B and A2Q.  In a process for making quick-cooking rice, rice grains are hydrated in water at a temperature below the gelatinization temperature of the rice, e.g. between 20 and 55‹C., until the rice grains attain a water content between 25 and 40% by weight. The hydrated rice gains are passed for a period of 3 to 10 minutes, intermittently through hot water, e.g. in the form of a series of sprays, having a temperature of at least 55‹C., e.g. between 80 and 100‹C., and an atmosphere of steam and are then passed, for another 3 to 10 minute period, intermittently through water, e.g. in the form of a series of sprays having a temperature below 55‹C., and an atmosphere of steam. Cleaned brown or white milled whole rice grains, preferably fissured by pre-treatment with infra-red rays or dry air having a temperature not exceeding 150‹C., are fed, from a bin 10, Fig. 1, into a hydrator 20 into which water is fed from a tank 22 through a pipe 24 and a valve 25 controlled by a float 26. The rice grains may remain in the hydrator for 120 minutes. They are discharged through a metering device 30 and an outlet 31, on to the upper flight of a foraminous or reticulated endless wire screen conveyer 32 and may be subjected to a blast of air, from a nozzle 34, as they are discharged. A spreader 46 distributes the hydrated grains evenly on the flight of the conveyer, e.g. in a layer one-half to one inch in thickness. Excess water drains off into a tank 36 and a sump 38, from which it is returned to the tank 22 through a pump 40, filter 42 and pipe 43. The hydrated grains are then carried through a gelatinizer 50 comprising an open tank 52 positioned under the upper flight of the conveyer. Perforated steam pipes 54 are disposed in the tank, preferably submerged in water contained therein, to direct steam, preferably wet steam, through the upper flight of the conveyer and the layer of rice grains. The time taken for the rice grains to be conveyed through the gelatinizer is 6 to 20 minutes. Hot water is sprayed on to the rice grains through a series of nozzles 56, preferably depressed downwardly, e.g. at an angle of 45 degrees, in the direction of movement of the layer of rice grains. The nozzles 56 are spaced apart, so that the time taken for rice grains to be conveyed from one hot water spray to the next is 15 seconds. Cooler water is then sprayed on to the rice grains through a series of similar nozzles 58, which are spaced apart so that the time taken for rice grains to be conveyed from one cool spray to the next is 30 seconds. The rice grains are carried through all the hot water sprays in 3 to 10 minutes and through all the cooler sprays in 3 to 10 minutes. A hood 66 is located over the hot and cooler sprays to direct condensed steam downwardly on to the rice grains. The 85 to 95% gelatinized rice grains emerging from the gelatinizer have a water content between 50 and 65% by weight. They are cooled, if necessary, with water at a temperature between 10 and 55‹C., and/or by blasts of cold air from nozzles 68, and are then dried in hot air at a temperature between 80 and 140‹C. to yield quick-cooking rice having a moisture content between 10 and 14% by weight. Alternatively, the hydrated rice grains may be gelatinized by being carried, on the upper flight of a reticulated endless belt 32, through a gelatinizing chamber 78, Fig. 5, provided with a cover. The base of the chamber is partitioned to form compartments A, B and C holding water at different levels, so that water overflows from compartment C to B and B to A. Perforated steam coils (not shown) are located in the chamber to heat the water, so that its temperature rises from a temperature below 55‹C. in compartment C to a temperature above 55‹C., e.g. to 100‹C., in compartment A, and to provide an atmosphere of wet steam over the water. The upper flight of the belt 32 is guided by means (not shown) in a zig-zag path through the water and wet steam. The rice grains are sprayed at a location 79 with water at a temperature between 20 and 85‹C. The gelatinized rice grains leaving the gelatinizer 78 are subjected to an upward blast of air 80, at a temperature up to 60‹C., to cool and loosen the grains and arrest gelatinization. The water for treating the rice may contain tomato powder, onion or garlic flavouring, carotene, vitamins and a vegetable protein, such as soya protein.