| Barley grains (waxy and regular) were pearled to different extents. The composition of pearling products (PF and PG) and the gel color of PG-flour were investigated. The PG-flour was then subjected to extrusion studied with and without alpha-amylase. Effects of extrusion conditions and alpha-amylase concentration on the degree of hydrolysis and dextrose equivalent, oligosaccharide composition, IDF, SDF and TDF of the extruded flours were studied. The study indicated that 32% of pearling is required to ensure the bright color of barley-based foods. Extrusion of barley flour with 4% alpha-amylase at 100°C and 50% moisture level lead to the maximum degree of hydrolysis. At each temperature and enzyme concentration, the saccharide composition (DPI-7), followed the order: DP2>DP6>DP3>DP5>DP7>DP4>DP1. Extrusion cooking increased the TDF and SDF contents of barley flours while IDF was decreased in CDC-Candle but increased in Phoenix. Overall, it was demonstrated that the dextrinized barley flour with different oligosaccharides and dietary fiber profile could be produced by extrusion processing. |
