GB995729A - Improvements in or relating to the modification of rice - Google Patents

Abstract

In producing modified rice grains which are particularly suitable for rice puddings, the moisture content of milled rice grains is raised, uniformly throughout them at a temeprature below the gelatinizing point of the starch therein, to a value between 18 and 30%, preferably between 22 and 28%, by weight, and the moist grains are then heated to expel moisture rapidly, e.g. to reduce their moisture content to between 10 and 14%, and thus create fissures in the grains and increase their porosity. The milled rice grains may be treated with humid air until they absorb sufficient moisture. Alternatively, the milled rice grains may be soaked in, or sprayed with, water for 30 minutes at 20 DEG C. or for 10 minutes at 55 to 60 DEG C., then centrifuged to remove surface moisture and conditioned, as by being contained in a closed space for 30 minutes to 4 hours at 20 DEG C., or retained, for 10 minutes at 55 DEG C., in a current of air having a relative humidity between 80 and 90%. The moist grains may be heated by infra-red or dielectric, e.g. radio-frequency, heating. Alternatively, the moist grains may be heated by passing air or inert gas, having a temperature between 90 DEG and 120 DEG C., over and/or through them for 2 to 6 minutes, as by carrying a thin (0.75 inch) layer of moist grains on a travelling, permeable, e.g. perforated, belt through a dryer and blowing heated air or inert gas upwardly through the grains on one portion of the belt and then downwardly through the grains on another portion of the belt. The dried grains may then be cooled, as by passing air at room temperature downwardly through them as they are carried on the belt.