The present invention provides a basal cell culture medium and a feed medium with novel amino acid ratios and/or iron choline citrate as iron carrier that result in improved performance of mammalian cell culture processes, such as CHO cultivation and protein production processes, in particular in increased product titer (e.g. of monoclonal antibodies). Also provided are methods for culturing mammalian cells and producing a protein of interest using said basal cell culture medium and optionally feed medium. The invention also provides for a medium platform that comprises (i) the basal cell culture medium and (ii) the feed medium.
