said condensation is carried out at an alkaline ph preferably at a ph of between 8 and 10 the alkaline ph is obtained by adding an alkali metal hydroxide preferably sodium or potassium hydroxide to the aqueous medium when the condensation has been performed the product is recovered by means of centrifugation of the precipitated product after adjusting the medium to a practically neutral ph preferably to a ph of between 6 and 7 by adding an inorganic acid preferably hydrochloric acid preferably in the process of the invention the esterification of the amino acid with c1 c12 alcohols especially ethanol takes place by adding thionyl chloride to a suspension prepared at room temperature of arginine in alcohol the process of the invention differs from the previous processes both in the esterification step and in the condensation step in the esterification step the same reactants and the same catalyst are used as in patent es 512643 but the reaction sequence is different the reactants arginine and ethanol are not mixed simultaneously with the catalyst thionyl chloride instead the catalyst is added subsequently to the reactants in this way the reaction of the invention is exothermic so that the heat evolved is exploited with a corresponding energy saving during this phase of the process in the condensation step the components are different thus for example in patent es 512643 dmf dimethylformamide dicyclohexylcarbodimide and a fatty acid are used while in the invention water caustic soda and a fatty acid chloride are used this step thus entails a condensation of the fatty acid chloride in an aqueous medium the hydrochloride of the corresponding derivative being separated consequently the process of the invention differs substantially from the.