Characteristics and utilization of dry roasted air‐classified navy bean protein fraction

Abstract

AbstractNavy beans,Phaseolus vulgaris, were dry roasted in a particle‐to‐particle heat exchanger, dehulled by air aspiration, pin‐milled and air‐classified to yield a high protein fraction. Proximate analyses, nitrogen solubility indices and oligosaccharide contents of this high protein fraction as influenced by processing parameters which affected final product temperature were determined. Farinograms of wheat/bean protein fraction composite flours were run. A high‐protein bean flour fraction was selected from these dry and roasted treatments and used in product development. Quality characteristics and consumer acceptability of high‐protein prototype products were evaluated. Results of this research indicate that the dry roasting process influences the characteristics of the air‐classified protein fraction. Flour color, nitrogen solubility and dough mixing properties were most greatly influenced by roasting time and temperature. Increased roasting resulted in increased browning and decreased nitrogen solubility and dough mixing stability. Wheat flour bread products, substituted with low levels of high‐protein bean flour, were of high quality.