Spectroscopic analysis of the benchmark system α Aurigae Binaries play an important role in observational and theoretical astrophysics. Since the mass and the chemical composition are key ingredients for stellar evolution high resolution spectroscopy is an important and necessary tool to derive those parameters to high confidence in binaries. This involves carefully measured orbital motion by the determination of radial velocity (RV) shifts and sophisticated techniques to derive the abundances of elements within the stellar atmosphere. A technique superior to conventional cross correlation methods to determine RV shifts in known as spectral disentangling. Hence a major task of this thesis was the design of a sophisticated software package for this approach. In order to investigate secondary effects such as flux and line profile variations imprinting changes on the spectrum the behavior of spectral disentangling on such variability is a key to understand the derived values to improve them and to get information about the variability itself. ...