A better control of the foaming process is important for food industry, as the structure of the liquid/gas mixture is a key parameter for the end-used properties of foams.

Emeline Talansier, GEPEA-UMR-CNRS, Nantes Cedex, France, and colleagues focused on the valorization of egg white proteins (EWPs) and present a method to optimize the operating conditions or to adapt the formulation. The method allows studying the effect of the process parameters on the foam structure and the effect of the thermal pretreatment of the EWP in the dry state on the rheology and the stability of foams.

The foaming is achieved with a SMX10 static mixer. It allows the production of controlled structure foams which makes it possible to investigate the dependence of foam properties by comparing foams with the same alveolar structure in relation with their formulation. The SMX foaming process is suitable for the elaboration of foam with controlled structure. This is ensured by the complete mixing of the gas and the liquid flow rates, contrary to batch processes where the overrun depends on the liquid properties.

Nevertheless, there is still a lack of knowledge in the process hydrodynamics to propose an accurate design at industrial scale. The reseachers presently work on a model based on a breakup model along the mixer.

• Elaboration of Controlled Structure Foams with the SMX Static Mixer,
  Emeline Talansier, Dominique Dellavalle, Catherine Loisel, Anne Desrumaux, Jack Legrand,
  AIChE J. 2012.
  DOI: 10.1002/aic.13796