Effect of Lipids on the Properties of Extruded Products

Corn gluten having 3.9, 1.8 and 0.2%, lipid (dry basis, db) was blended with defatted soy protein concentrate in the ratio of 25:75 w/ w. The blends were made up of 20, 30, and 40% moisture (db) and then extruded through 4.24, 3.0, and 2.12 mm diameter dies at screw speeds of 60, 120, and 180 rpm. The dependent variables measured were puff ratio, bulk density, shear strength, and water‐holding capacity. Shear strength increased when lipids decreased from 3.9% to 1.8% but then decreased when lipids were reduced to 0.2%. Water‐holding capacity and puff ratio increased with decreasing lipids. Bulk density was unaffected by lipid concentration.