Optimization of Protein Isolate Production From Soy Flour Using Industrial Membrane Systems

A new approach to the production of protein isolates from oilseed flours with industrial ultrafiltration and reverse osmosis membranes previously demonstrated has been further optimized for use with soy flour. The effects on membrane performance of prefiltering the flour extract feed to different degrees and processing the feed at different pH levels were examined. A wide range of industrial membrane systems embodying several configurations was tested. Prefiltration of feed to less than 100μ proved to be unnecessary for most systems. Feed at pH 7.0 processed at high permeation rates and yielded products with NSI values in excess of 90.