Foam Stabilizers

foam stabilizers are chemical compounds that retard the coalescence of gas bubbles in a foam making them more stable and uniform. These stabilizers are used in food and drinks.

The foaming process occurs when air is mixed with liquid and a gas is trapped by the protein molecules aligned between the water and air. The hydrophobic end of the proteins dangle in the water while the hydrophilic ends point into the air forming a bubble that looks like a foam.

Nanoparticles as Foam Stabilizer

Nanoparticles are widely recognized for their potential to be applied in foam stabilization. However, there are several challenges in the use of nanoparticles for this purpose. These challenges include the synthetic routes, properties of nanoparticles and environmental concerns (Rafati et al., 2016).

Control parameters for Foam Stability

The main control parameters in foam stability include the size of nanoparticles, type of nanoparticles, reservoir temperature, salt concentration and modifiers. The smaller size of nanoparticles could stay on lamellae stably and prevent the drainage, while the larger size would be difficult to maintain and increase the diameter of the nanoparticles (Pugh, 1996; Singh and Mohanty, 2015).

Among different types of nanoparticles, moderate hydrophobic (contact angle 90 deg) nanoparticles were optimum for foam stabilizers. They enhanced maximum capillary pressure, increased the mechanical strength of lamellae and formed network structure to minimize film drainage, reduce the coalescence of bubbles and extend the existence time of the foam system.