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Cellular films have been produced through evaporation of aqueous dispersions containing latex particles. The membranes of the cells are made of hydrophilic species which originate from the surfaces of the particles; they form a periodic structure which separates the cell cores from each other. Thermal treatments have been applied to induce the fragmentation of membranes. The resulting structural changes have been observed through small-angle neutron scattering and electron microscopy. It has been found that the fragmentation of membranes is controlled by three parameters: the mobility of membrane polymers, the anchoring of these polymers on the core, and the mobility of the core. After fragmentation occurs, the hydrophilic membrane material is expelled to large lumps immersed in a continuous latex matrix.

As a molecular model of gelatin-free coacervates, complexes of pea globulin and alpha gliadin proteins with gum arabic prepared at different acidic pH values are studied using Raman microspectrometry. Raman spectra confirm higher content of beta-sheets and random coils in pea globulin and dominating alpha-helical structures in alpha gliadin. For protein-gum arabic complexes, Raman data support the existence of specific pH conditions for optimal complex coacervation (pH 2.75 for globulin and pH 3.0 for gliadin(1)), when (i) pH-induced conformational perturbations of free protein structure are the strongest and (ii) compensation of these perturbations by gum arabic is the most pronounced. Conformations implied in the protein-gum complexes are mainly beta-sheets in pea globulin and alpha-helix in alpha gliadin. The role of electrostatic and non-Coulombic interactions (intermolecular hydrogen bonds) in stabilizing of protein-polysaccharide complexes is discussed in relation with the overall structure and the charge density profile of these two proteins.