FUNCTIONAL PROPRETIES OF RAPESEED FLOURS, CONCENTRATES AND ISOLATE

Abstract

ABSTRACT The functional properties of rapeseed meal, flours, protein concentrates and isolate were evaluated in comparison with those of soybean. Generally, rapeseed products were lower in protein but higher in crude fiber and ash contents than the corresponding soybean flour, concentrate or isolate, Rapeseed flours were comparable to soybean flour in water absorption but showed much higher nitrogen solubility, fat absorption, oil emulsification, whippability and foam stability. The viscoamylograph curves for rapeseed flours were characterized by intermediate peak and high cold viscosities, but their gelation properties were poor. Unfortunately, flour from the low glucosinolate cultivar, Tower, contained 1.2 mg/g of glucosinolates, primarily oxazolidinethione, and only the detoxified concentrates and isolate would be safe for human consumption. Rapeseed concentrates and isolate showed excellent water‐and fat‐holding capacity and the isolate was high in oil emulsification and whipping characteristics. While superior to soybean products in most functional tests, the utilization of rapeseed products may be limited by green or brown colors in the aqueous slurries.