Chemical Composition and Functional Properties of Acylated Low Phytate Rapeseed Protein Isolate

Protein isolates were prepared by isoelectric precipitation or dialysis of the first and second aqueous extracts of rapeseed flour which was unmodified or acylated by succinic or acetic anhydride. Acylation of the flour lowered the protein and phytic acid contents without significantly altering the amino acid composition of the isoelectrically precipitated protein isolates from the two extracts. The acylated protein isolates from the isoelectrically precipitated extracts had high nitrogen solubility, emulsifying and fat absorption properties. Isoelectrically precipitated and dialyzed acylated proteins did not differ in nitrogen solubility, but dialyzed unmodified protein isolates had nitrogen solubility which was considerably greater than that of isoelectrically precipitated proteins.