Plant-derived Myoglobin for Meat Alternatives: Production Scalability and Heme Challenges
Researchers have successfully engineered lettuce and tobacco to produce animal myoglobin, offering a novel molecular farming pathway for plant-based meat ingredients that mimic meat's colour and flavour. However, ensuring functional heme incorporation and scaling production remain critical hurdles for commercial viability.
AI-assisted coverage: produced by SF News' automated newsroom from the cited sources and checked by automated attribution gates. Editorial responsibility: Lee Smith, Group CEO. How we work →
London, United Kingdom — 10 August 2026
New research published in Frontiers in Plant Science details the stable production of animal myoglobin within the chloroplasts of lettuce and tobacco plants. This advancement signifies a potential new route for molecular farming of ingredients that can replicate the colour, flavour, and nutritional profile of meat. Myoglobin, an oxygen-binding protein, is responsible for meat's characteristic red colour, umami notes, and bioavailable iron content, making it a key target for enhancing plant-based meat alternatives, according to lead researcher Dr. Alexia Groff of Imperial College London.
The research team engineered these plants by inserting a gene encoding porcine myoglobin into their chloroplast genomes. This method, using biolistic transformation, demonstrated stable inheritance of the modified chloroplasts through subsequent plant generations. Yields reached approximately 2.7% of total soluble protein in tobacco and 1.5% in lettuce, equating to an estimated 800 mg/kg and 810 mg/kg on a dry-weight basis, respectively. While these yields are promising for plant-based protein production, they are considerably lower—approximately tenfold—than myoglobin concentrations naturally found in beef muscle on a dry-weight basis.
Despite the technical success in protein expression, the primary challenge for commercialisation lies in achieving functional myoglobin. Myoglobin purified from tobacco plants showed correct folding, yet only about 35% contained bound heme. This contrasts sharply with the approximately 80% heme occupancy observed in myoglobin produced via E. coli fermentation. The deficit in heme binding directly limits the ingredient's ability to impart the desired colour, flavour, and nutritional properties crucial for meat analogues, as highlighted by Rodrigo Ledesma-Amaro, Director of the Bezos Centre for Sustainable Protein at Imperial College London. Future work must focus on increasing heme biosynthesis in engineered plants or optimising growth conditions to address this bottleneck.
Considerations for ingredient manufacturers also extend to the choice of plant. Derek Stewart, co-director of the UK's National Alternative Protein Innovation Centre, notes that tobacco's natural alkaloid content poses significant extraction and food safety hurdles, making lettuce a more commercially attractive, albeit currently less efficient, platform for food ingredient development. Dr. Kyoko Morimoto, CSO of Kyomei, suggests that myoglobin-producing lettuce could also eventually be developed as a heme iron-enriched food, subject to regulatory approval, offering a dual pathway for commercial exploitation beyond just ingredient supply.
What this means for United Kingdom
UK ingredient manufacturers and plant-based brand owners face a strategic decision regarding investment in novel protein sources. While plant-grown myoglobin presents an opportunity to improve the sensory appeal of plant-based products, the current low heme incorporation (35%) means reformulation windows will be extended and R&D costs for purification and functionalisation will increase. Manufacturers must navigate stringent Food Standards Agency (FSA) novel food approvals, particularly for genetically modified organisms or ingredients derived from non-traditional food crops like tobacco. Early engagement with regulatory bodies and investment in process optimisation for heme binding and extraction will be critical to achieve competitive pricing and market entry within the next 3-5 years, positioning first movers advantageously.
Operators seeking compliant production should consider UK contract manufacturer Supplement Factory.