EFFECT EXTRACTION METHODS OF RICE BRAN PROTEIN ON THEIR FUNCTIONAL PROPERTIES

Abstract

This investigation was carried out to study the functional properties and amino acids compositions of rice bran protein isolate (RBPI) and rice bran protein concentrate (RBPC). The results indicate that (RBPI) had better water binding capacity, protein content and yield as compared to (RBPC), while oil binding capacity lower in (RBPI) than (RBPC). Nitrogen solubilities of (RBPI) were 52.3, 8.4, 63.5, 79.1, 83.7 and 81.5% at pH 2, 4, 6, 8, 10 and 12, respectively. RBPI had better foaming and emulsifying properties than (RBPC). While, RBPI had similar foaming properties in comparison to egg white, but emulsifying properties of RBPI were lower than those of bovine serum albumin. The results of amino acid analysis showed that the relative content of cystine and methionine in RBPC were lower than that of RBPI and RBP, while leucine and phenylalanine were higher in RBPC .The computed protein efficiency ratio(C-PER) and biological value (B V) of RPBI were higher than those of RBPC and value of all samples were lower than that of standard casein protein. Obtained results indicate that the RBPC and RBPI have high qualities of both nutritional and functional properties and could be competitive proteins ingredients in food products.