Tomato leaves are not the most obvious option for an alternative protein source – and, let’s be honest, they don’t have much more to offer. But, their potential is surprising.
The protein content is up to 27 percent.
Can it be used to replace animal protein?
Is it possible to extract protein from the leaves of tomato plants?
It is possible to extract the protein from tomato leaves and use it as an alternative plant-based product. But achieving this at a large scale remains elusive.
Marietheres Kleuter’s PhD thesis explored the extraction.
Luisa Trindade explains that the protein could be extracted by alkaline techniques, but this is not the method of choice if the extraction were to take place in a commercial context.
Trindade says that you can get more protein out of younger leaves than older ones.
The protein in the leaves breaks down as they age into smaller molecules called peptides. Proteases, which are enzymes that breakdown proteins, cause this.
What can you do with tomato leaf proteins?
Rubisco is a protein that can be found in both duckweed and tomato leaves.
Rubisco is a key component of photosynthesis in plants. Rubisco can also be made into tofu by using it as an edible protein. It can, at least in an ideal situation. At this point, however, chlorophyll is a pigment that causes it to still appear green. Researchers worry, therefore, that the product will not be palatable by consumers.
Trindade says that Rubisco has similar properties to whey proteins.
Is tomato leaf protein commercially viable?
The problem is the effectiveness with which the extraction can be carried out. Trindade explains that you might only be able to extract 10% of the proteins, but there will still 90%. This efficiency needs to be improved if the protein is going to become commercially viable.
50 percent of the proteins are insoluble and must therefore be removed in another way. This leaves behind a large amount of soluble proteins that are not extracted.
This problem can be resolved in two ways: develop improved extraction methods or alter the plants being used.
Research is being conducted to enhance the extraction method and also the viability for the plants.
Trindade explains that the goal is to improve the new varieties by understanding the genetic factors which are the obstacles to the extraction.
Then I believe it would be commercially viable.
Global Food Tech Awards 2025
Are you proud of a recent food-tech invention? You still have time to apply for the European Heats of Global Food Teach Awards. Judges are searching for innovative ideas to shape the future of foods. The deadline is July 18. You can use your innovation to impact all parts of the supply chain for food and beverages, including alternative proteins, sustainable ingredients, AI-driven solutions and gut health. The winners will also be awarded a trophy and invited to present live on stage to industry leaders at the Future Food-Tech Summit in London, on September 24, where they can pitch to investors.
