Effect of particle characteristics and foaming parameters on resulting foam quality and stability

Abstract

In this study, the effects of ten different food-grade particles on bubble quality and stabilization of particle-stabilized food foams in batch and continuous foaming with and without polyglycerol ester (PGE) as an emulsifier were investigated. Particle properties, such as contact angle and porosity, and varying process parameters, such as shear rate and gas fraction, were assessed with respect to their impact on bubble size x50,0, bubble size distribution width and drainage.The smallest bubble size x50,0 in foams without PGE could be achieved with banana powder (88 μm), calcium carbonate (89 μm) and microcrystalline cellulose (79 μm) particles. In comparison, the smallest size in the reference without particles were 105 μm. Combining the use of particles with PGE further reduced bubble size by up to 57% and drainage by up to 100%. Increasing the shear rate from 4922 s−1 (35 μm) to 9844 s−1 (14 μm) resulted in smaller mean bubble sizes and significantly narrower bubble size distributions whereas no distinct correlation between gas fraction and resulting bubble size was found.This study shows that using suitable particles in combination with an optimized foaming process promotes both bubble quality and the stability of foams.