The present invention concerns a product taken from the group consisting of afoam, an emulsion, a foamed emulsion, a dispersed emulsion and a foameddispersion, wherein the interface water-air, water-oil or water-solidcomprises a complex formed instantaneously by the mixture of at least aprotein (or peptide) and at least a polysaccharide oppositely charged or themixture of two proteins oppositely charged, said product being in a pH rangewithin which the electrostatic interaction between both compounds oppositelycharged occurs and wherein the total amount of protein and polysaccharide iscomprised between 0.01 and 5 % in weight.
