Improve control over microorganism growth in bio-catalysis operations in order to reduce/avoid contamination without antibiotics Improve the techniques for microbial control in bio-catalysis. The improvements should include less cumbersome sterilisation steps and use of improved bio-catalyst microorganisms and process conditions to curb contamination, avoiding the use of antibiotics.Proposals should provide process yields at least comparable to the state-of-the-art. Proposals should also result in relevant improvements of the market value of by-products and side-streams, as compared with the current technologies.Proposals should assess the feasibility of scaling-up the developed solution and the potential for replication into a wide range of bio-catalytic processes and value chains, allowing a better and larger application of the innovative techniques with the aim of avoiding or controlling contamination.In addition, proposals should include high levels of safety and sustainability, from technical, economic and environmental points of view, required for feasible scale-up towards demonstration levels.The projects should cover any Technology Readiness Level (TRL) from 3 to 5. In the case of a pilot scale project (TRL 5), proposals should present a credible cost estimate for the proposed processes with a preliminary assessment of their competitiveness when scaled up.Proposals should also include an environmental and socio-economic assessment, for example with an LCA. In particular, when targeting TRL 5, proposals should include an LCA in order to evaluate the environmental and socio-economic performance of the developed processes.It is considered that proposals with a total eligible budget in the range of EUR 2-5 million would allow this specific challenge to be addressed appropriately. Nonetheless, this does not preclude submission and selection of proposals with another budget. With the introduction of several and different feedstock, the risk of contamination increases due to longer fermentation times and weaker genetically modified production organisms. This leads to more stringent requirements for control of contamination within the bio-catalysis reactor. The objective is to overcome this challenge without exacerbating cumbersome sterilisation procedures or increasing the use of antibiotics, which would spread antibiotic resistance in the microorganisms. The latter would reduce the overall efficiency of the processes and impose an increasing substitution of the currently utilised microorganisms with new and more resistant strains.In addition, residual antibiotics found in biorefinery side-streams hinder their potential use as a secondary feedstock for food/feed applications, as the EU regulatory framework in place needs to be taken into full account.Hence, the use of antibiotics in bio-catalytic processes, although beneficial in controlling microbial growth, presents several drawbacks mainly associated with the risk of increasing antibiotic microbial resistance, as well as with the reduction of market value of the side-streams containing traces of antibiotics because of regulatory aspects.The challenge is to develop other methods to control contamination. Alternatives include for instance microbial consortia (including synthetic consortia), non-antibiotic antimicrobials (like phages), more robust production microorganisms and more suitable bio-reactor conditions. These new methods should lead to expanding the potential feedstock basis and promoting the market position of bio-catalytic processes by: improved tools, methods and production organisms; repressing contamination to the level that complies with the end-use of the products (e.g. compliant to limits in feed or food applications), while avoiding or reducing the use of antibiotics. The result could be a wider market deployment of by-products and residues, and technical and environmental benefits from limiting antibiotics resistance. New bio-catalytic tools, methods, processes and microorganisms with a greater resistance against contamination and capacity for longer duration fermentations, including continuous fermentation. Technical and economic improvements in the management activities of bio-catalytic processes, especially the reduction of 20% of the costs associated with the control of the microbial growth. Introduction of new routes and technologies for bio-based processes able to reduce their scale-up time as well as the time-to-market of the resultant products. Improved competitiveness of the new bio-based value chains as compared to the existing ones. Contribution to the BBI JU Key Performance Indicators (KPI), specifically: Set the foundation of at least 1 new bio-based value chain (KPI 2).