Evaluating of quality of rice bran protein concentrate prepared by a combination of isoelectronic precipitation and electrolyzed water treatment

A combination of isoelectronic precipitation and electrolyzed water treatment (IP-EWT) process was use for simultaneous recovery of protein and phosphorus compounds from heat-stabilized defatted rice bran (HSDFRB). The highest protein content (65.1 w/w%) recovery ratio (over 50%) of protein concentrate were attained by two-stage protein extraction with IP-EWT. Analysis of amino-acid composition demonstrated excellent amino acid value (76.6%) in the protein fraction than those of commercial cereals such as rice (61%), wheat (39%), and corn (31%). In addition, according to SDS-PAGE and immunoblotting analysis, neither rice allergenic protein nor heavy metals were detected in either HSDFRB or protein fractions extracted by IP-EWT. These results suggest that as an eco-friendly process, this combined (IP-EWT) process is suitable for practical recovery of highly concentrated and safe protein from HSDFRB without using enzymes or chemicals such as organic solvents, buffering agents, and surfactants.