Microbial cultivation conditions impact the quality and techno-functional properties of microbial biomass for meat analogue applications

Meat analogues have gained traction as they provide a more sustainable and ethical alternative to traditional meat, with microbial biomass being a promising feedstock due to its nutritional value and potentially environmentally-friendly production. However, it remains unclear whether the microbial cultivation conditions influence its processability and applicability for conversion into meat analogues. This study explored the effects of microbial cultivation parameters, such as salt (NaCl) levels in the medium and cultivation temperature, on the quality of the biomass from the Gram-negative bacterium Paracoccus zeaxanthinifaciens for hybrid meat analogue production (1:1 w/w microbial biomass to wheat gluten). Cultivation in bioreactors under five different conditions revealed substantial impacts on the macromolecular composition, physicochemical, thermal and rheological properties, and the ability to create a texturized meat analogue. Overall, the cultivation at temperatures below the optimal levels for growth yielded the most promising results. Specifically, biomass cultivated at low temperature yielded the highest total amino acid content and strongest fibers in a texturized meat analogue, whereas cultivation in high salt levels increased the lipid content. Microbial biomass grown under control and low-temperature conditions formed strong fibers suitable for texturized meat analogues, but cultivation at high salt and high temperature compromised texturization via shear cell, with the latter yielding unstructured paste. This study highlights for the first time the importance of optimizing cultivation conditions to enhance the quality and functionality of microbial biomass as a feedstock for meat analogue production.