Effect of pH and interaction between egg white protein andhydroxypropymethylcellulose in bulk aqueous medium on foamingproperties

Abstract

Egg white protein (EW) is used as surface-active ingredient in aerated food and hydroxypropylmethyl-cellulose (HPMC) is a polysaccharide that behaves as a surfactant. This study aimed at investigating theeffects of process parameters biopolymer concentration (2.0–5.0%, w/w), EW:HPMC ratio (2:1–18:1), pH(3.0–6.0), and the influence of biopolymers’ behavior in aqueous solution at different pH on the foam-ing properties (overrun, drainage, and bubble growth rate). Process parameters had effect on foamingproperties. The pH was the major factor influencing the type of EW/HPMC interaction and affected thefoaming properties of biopolymer mixture. At pH 3.0, EW and HPMC showed thermodynamic compat-ibility leading to better foaming properties, higher foaming capacity, and stability than without HPMCaddition whereas at pH 4.5 and 6.0, EW and HPMC are incompatible that causes lower stability concerningthe disproportionation comparing to foam without HPMC. At pH between 3.0 and 4.5, HPMC improvesfoaming properties of aerated products.