Processing thin stillage, comprises (a) feeding thin stillage into a working container (3), (b) concentrating the thin stillage in a filtration system (9), and (c) recycling an initial partial flow of the concentrated thin stillage to the thin stillage containing in the working container, to adjust total dry substance content. An independent claim is also included for a device for producing a protein-containing valuable product of the thin stillage, comprising a working container, a filtration system, a centrifuge, preferably a separator (16), and a drying device, where the filtration system is connected to the working container via a feedback (17) for an initial partial flow of the concentrated thin stillage.
