Optimization of foaming and stabilizing process parameters for foam mat drying of prickly pear (Opuntia elatior Mill.) pulp

Abstract

Foaming of prickly pear pulp was carried out by using foaming agent and foaming stabilizer for drying in thin layer. Whey protein isolate was used as foaming agent and methyl cellulose was used as foaming stabilizer. Based on preliminary trials pectin (0.375%, w/w) was added as thickener and stabilizer. The effect of three foaming parameters viz., foaming agent (2.5, 5.0, 7.5, 10.0 and 12.5%, w/w), foaming stabilizer (0.0, 0.125, 0.250, 0.375 and 0.5%, w/w) and whipping time (5, 10, 15, 20 and 25 min) were optimized on maximum foam expansion, maximum foam stability and minimum foam density of prickly pear pulp using response surface methodology. The optimum foaming conditions were found to be 5.36% foaming agent, 0.50% foaming stabilizer and 12.08 min whipping time. At this condition, it would be possible of foaming properties of prickly pear pulp with a foam expansion of 405.28%, foam stability of 81.25% and foam density of 0.25 g/cc.