Beef Protein Grown Inside Plants Offers Alternative to Lab-Grown Meat

Scientists have developed a method to cultivate beef muscle protein within lettuce and tobacco plants, offering a potential alternative to traditional lab-grown meat. The breakthrough, achieved by researchers at Imperial College London, involves engineering plants to produce myoglobin, a protein that gives meat its characteristic color and flavor.

This approach utilizes plants as a biological factory, embedding genes for animal protein into chloroplasts, the sites of photosynthesis. "Plants can be engineered to produce the animal protein myoglobin (Mb) in their chloroplasts," explained Dr. Alexia Groff. "This could provide a sustainable way to produce an important ingredient for plant-based meat products."

The research focused on myoglobin, the iron-rich protein responsible for meat's umami taste and red hue. Scientists cloned genes for pig and cattle myoglobin and then used a gene gun to introduce these genes into the chloroplasts of tobacco and lettuce seedlings. Tobacco was chosen as a model plant for technology development, while lettuce was selected as an edible crop with potential for future food ingredient production.

After the plants matured and flowered, their offspring inherited the myoglobin genes. Subsequent measurements indicated a yield of approximately 800mg/kg of tobacco and 810mg/kg of lettuce. While this yield is lower than that of real meat, the researchers highlighted the resource efficiency of plant cultivation compared to livestock production. "Plant-derived Mb [myoglobin] could achieve protein yields per hectare that rival – or even potentially exceed – those of animal agriculture, while also benefiting from substantially lower water use and greenhouse gas emissions," the study stated.

This development comes at a time when global efforts are underway to reduce meat consumption. For instance, the UK has committed to a legally binding goal to cut carbon emissions by 87 percent by 2040, which necessitates a significant reduction in household meat and dairy intake.

The next step for the research team is to develop an industrial purification method for the plant-derived myoglobin. "The myoglobin could be extracted from leaves and purified using industrial protein purification methods," Dr. Groff said. "Since it is identical to animal myoglobin, it could then be added as an ingredient to plant-based meat products to improve their color, flavor and nutritional value."

Professor Derek Stewart, Co-Director of the National Alternative Protein Innovation Centre at the James Hutton Institute, described the study as an "exciting step forward." He noted the significance of proving the concept that plants can produce myoglobin in a stable and scalable manner, particularly that the recovered protein was properly folded and bound to heme, which is crucial for meat-like characteristics.