Process for producing an active ingredient-containing foam comprising a protein and also a fat and/or a wax, comprising the following steps: A) providing the fat and/or the wax (fatty acid ester component) and the protein component, wherein - the fatty acid ester component and/or the protein component comprise a foam-stabilizing constituent which comprises or consists of a foam-stabilizing protein present in the protein component and/or a foam-stabilizing constituent present in the fatty acid ester component, - the protein component and the fatty acid ester component are present in a ratio by weight from 1:10 to 10:1, - the fatty acid ester component consists of a plant oil or a plant wax - wherein the protein component comprises or consists of a plant protein, especially a cereal protein, a pulse protein or a potato protein, or an egg protein or a milk protein, - at least one pharmaceutical and/or cosmetic active ingredient has been introduced, is introduced or can be introduced in step C) into the fatty acid ester component, B) mixing the protein component and the fatty acid ester component with addition of a thickener and with addition of water, so that water and the total proportions of protein component and fatty acid ester component are present in a ratio by weight from 1:1 to 20:1 and wherein the proportion of fatty acid ester component in the resulting mixture is greater than 3% by weight, wherein no synthetic or partially synthetic surfactants are admixed, C) introducing a fat-soluble gas selected from nitrogen, nitrous oxide, xenon and mixtures thereof into the mixture obtained according to step B) such that a foam is formed. A) providing the fat and/or the wax (fatty acid ester component) and the protein component, wherein - the fatty acid ester component and/or the protein component comprise a foam-stabilizing constituent which comprises or consists of a foam-stabilizing protein present in the protein component and/or a foam-stabilizing constituent present in the fatty acid ester component, - the protein component and the fatty acid ester component are present in a ratio by weight from 1:10 to 10:1, - the fatty acid ester component consists of a plant oil or a plant wax - wherein the protein component comprises or consists of a plant protein, especially a cereal protein, a pulse protein or a potato protein, or an egg protein or a milk protein, - at least one pharmaceutical and/or cosmetic active ingredient has been introduced, is introduced or can be introduced in step C) into the fatty acid ester component, - the fatty acid ester component and/or the protein component comprise a foam-stabilizing constituent which comprises or consists of a foam-stabilizing protein present in the protein component and/or a foam-stabilizing constituent present in the fatty acid ester component, - the protein component and the fatty acid ester component are present in a ratio by weight from 1:10 to 10:1, - the fatty acid ester component consists of a plant oil or a plant wax - wherein the protein component comprises or consists of a plant protein, especially a cereal protein, a pulse protein or a potato protein, or an egg protein or a milk protein, - at least one pharmaceutical and/or cosmetic active ingredient has been introduced, is introduced or can be introduced in step C) into the fatty acid ester component, B) mixing the protein component and the fatty acid ester component with addition of a thickener and with addition of water, so that water and the total proportions of protein component and fatty acid ester component are present in a ratio by weight from 1:1 to 20:1 and wherein the proportion of fatty acid ester component in the resulting mixture is greater than 3% by weight, wherein no synthetic or partially synthetic surfactants are admixed, C) introducing a fat-soluble gas selected from nitrogen, nitrous oxide, xenon and mixtures thereof into the mixture obtained according to step B) such that a foam is formed. <EOS>