METHOD FOR OBTAINING A STARCH-FREE BRAN EXTRACT, A REFINED PRODUCT AND MATERIAL RESULTING FROM THIS METHOD

摘要

The invention concerns a method for obtaining a starch-free bran extract and a cellulosed refined product, consisting in the following steps: a) mixing the bran with ten times its water volume at a temperature less than 50 DEG C and filtering it so as to recuperate starch milk and starch-free bran, the starch milk being then decanted, filtered or centrifuged, then dried; this step is repeated twice to obtain a starch-free bran with a starch content less than 1 % of dry matter by weight; b) contacting the starch-free bran with an aqueous sodium solution with a concentration ranging between 2 and 12 % by volume, in a liquid/solid ratio ranging between 5 and 100, at a temperature ranging between 20 and 100 DEG C, for a duration ranging between 5 and 120 minutes; then in diluting the mixture with water, if required, until a liquid/solid ratio higher than 25 is obtained and the solid residue is separated by filtering and by drying; in concentrating the filtrate, acidifying it to a pH ranging between 4.5 and 7, and precipitating with ethanol in a ratio of 2 to 4 volumes of alcohol for one volume of solution to obtain a coagulum, which is dried for obtaining an extract rich in hemicellulose. The invention is applicable to wheat bran.