| A snack food containing whey protein, normal cornstarch, and pregelatinized waxy cornstarch was extruded in with three dietary fiber types (powdered cellulose, wheat fiber, and oat fiber). The fibers replaced the normal cornstarch at 30, 60, and 80% yielding extrudates with three fiber levels (18, 36, and 48%). Extrudate characteristics were evaluated on physical (expansion ratio, air cell size, density, and breaking force), chemical (moisture content, water absorption index, water solubility index, water and total soluble protein, and water soluble carbohydrate), and dependent extrusion parameters (pressure, motor torque, barrel and die temperature of the mix, barrel and die temperatures, residence time, and product flow rate). The physical and chemical characteristics of the extrudates were affected by fiber type and fiber level interaction while the dependent parameters were influenced by the fiber level in the extrudates. The possibility exists to incorporate fiber into an extruded snack food. |
