In many industrial applications impurities such as surfactants occur. These interfacially active molecules adsorb at liquid-liquid interfaces where they influence the occurring transport processes, which again affect reaction rates of multiphase reactions or contact times in extraction columns etc. To quantify the influences on the given applications, the interfacial coverage of the liquid-liquid interface with surfactant molecules must be known. The measurement of the fluid dynamics of single droplets provides a sensitive tool to capture any interfacial phenomena which changes the interfacial characteristics. This method was tested by applying two different surfactants in the system water/1-octanol. In some cases, the determination of the fluid dynamics provides a more reliable method for determining changes of the interfacial characteristics than the measurement of the interfacial tension.