Different processing industries produce production side streams which were in the past and still are producing environmentally burdening wastewater and solid wastes. With the newly developed process equipment and tools as well as with the new insights into the characteristics and activity of organic substances, numerous components of the processing side-streams can be extracted, reused and valorised into added-value products. However, a lot of approaches need technology scale-up tests and market development activities. One such potential shows whey and its derivates produced during cheese production. In the project, we evaluated the technical, commercial and financial feasibility of the technological approach toward complete whey utilisation by selective separation of individual whey proteins and the utilisation of residues for the production of protein-rich supplement for animal feed and the production of selected lactic acid bacteria with their bioactive metabolites.