Effect of Surfactant Type on Foaming Properties of Milk

The presence of low molecular weight surfactants is suspected as one of the causes of poorly foaming milk, as they can interfere with milk proteins in the formation and stabilization of foam. Here, we explore the effect of various surfactants on the foaming properties of reconstituted skim milk powders. Each surfactant is different in electrical charge and molecular weight, including cleaning O- and E-coded chemicals, Tween 80, sucrose stearate, sodium oleate, sodium dodecyl sulfate, cetyltrimethylammonium bromide, benzalkonium chloride, and lecithin. The results showed that surfactants had different effects on foamability, foam stability, and structure, due to their varied effects on milk properties (e.g., pH, zeta potential, and surface tension). E-coded chemicals and sucrose stearate markedly decreased milk foamability, while the impact of Tween 80 and lecithin was considered detrimental to foam stability, as they mostly induced the production of large air bubbles in the foam.