Microbial Hydrolysates as Amino Acid Source in Cell Culture Media for Cellular Agriculture

The high cost of cultivation media remains one of the barriers to the commercialization of cultivated meat. Current serum-free media reduce reliance on fetal bovine serum but only achieve modest cost savings. Especially at larger scales (> 20 m³), pharmaceutical-grade amino acids and recombinant proteins remain major cost drivers. Techno-economic analyses suggest that replacing purified amino acids is essential to achieve price parity with conventional meat. Microbial hydrolysates, also referred to as extracts, offer a promising alternative, as these can supply complex mixtures of amino acids and peptides at lower cost and with greater scalability than chemically defined formulations. In particular, yeast and bacterial extracts combine high protein (and therefore high amino acid) content, rapid growth, and established industrial-scale production. Comparative analyses indicate that microbial amino acid profiles broadly overlap with those of animal cells and traditional meat, but this similarity does not translate into meeting cellular amino acid demand. Consumption data indicate that key amino acids, such as glutamine, cysteine, serine and arginine, would be supplied insufficiently by microbial extracts. This mismatch highlights the need for engineering of microbial biomass and optimization of extraction methods. Extraction methods such as autolysis, enzymatic lysis, or physical disruption strongly influence nutrient release and composition, underscoring the need for standardizing microbial extract preparation. In addition, challenges remain in ensuring consistency, safety, and bioavailability of nutrients, as microbial extracts also contain nucleic acids and potential toxins. This review summarizes current knowledge on microbial hydrolysates for cultivated meat media, including biomass composition, extraction methods, and analytical tools to assess quality and performance. We identify key knowledge gaps, particularly in quantitative amino acid consumption data for relevant cell lines and performance testing in scalable cultures. Addressing these gaps could enable cost-effective media development and accelerate research toward sustainable, commercially viable cultivated meat.