Enrichment of protein, starch, fat, and sterol ferulates from corn fiber by fine grinding and air classification

Corn fiber contains hemicellulose, starch, cellulose, protein and fat. Ther e is commercial interest to produce sterol ferulates from corn fiber oil, w hich accounts for only 3% of corn fiber by weight. An inexpensive process t o enrich starch, protein, and fat contents of corn fiber is desirable for i ncreased utilization and further processing, This study was conducted to de termine whether fine grinding and air classification of corn fiber into sep arate fractions according to particle size could enrich selected components of interest. Corn fiber was finely ground in a pin mill at high speed, and the resulting ground fiber was separated into various fractions with cutpo ints of 15, 18, 24 and 30 mum, The finest fraction, with a particle size of less than 15 mum, showed enriched protein, starch, fat and sterol ferulate s contents compared with the starting corn fiber. The greater than 30 mum, fraction was separated by sieves into five fractions. In general, protein, starch, fat and sterol ferulates contents of the fractions decreased and to tal dietary fiber increased with increasing particle size. Fine grinding an d air classification of corn fiber can enrich protein, starch, fat and ster ol ferulates contents in the fine fractions and can make further processing more economical. Published by Elsevier Science B.V.