The leaves of many plants are a good source of protein: amaranth, spinach, lettuce, kale, alfalfa, as well as the leaves from plants that produce other edibles: beans, grains, sweet potato, etc. The main problem with leaves as a protein source is that the leaf itself is too high in water and fiber to make eating leaves practical as a source of protein. How much salad can you consume?
The fresh Leaf Protein Concentrate is about 25% protein; when dried, LPC is about 50% protein. This percent of protein is less than it is for protein isolates, but higher than most high protein whole foods. Most cheeses are 30% protein or less. Dry non-fat milk is about 35% protein. Fresh whole egg is only about 12% protein. Tuna, red meat, pork, poultry, legumes, seeds, and nuts are typically 20 to 30% protein. Dried soybeans top the list of whole food protein sources at about 36% protein. So even though leaf protein concentrate has less protein than any protein “isolate”, it has much more protein than most whole food sources of protein.
I know what you are thinking. You would rather eat any of the above-listed foods before you would eat LPC. Of course. So would I. But LPC is suitable as a survival food. When all other foods fail, leaves are edible when processed into LPC.
How do you make LPC? See the free PDF file (the printed book is ten dollars) here:
Leaf for Life handbook.
What is the best LPC crop? Duckweed. The yields from duckweed are extraordinarily high, and the dried leaf, before processing into LPC, is 35% protein.
Will LPC ever become a commercial product? I think that the future will see increasing problems with our food production and distribution system, and a need for crops that produce a high amount of protein per acre. Leaf protein could become a successful commercial product, only if it is further refined into leaf protein isolate. This would remove the green color and leaf taste, from the LPC, and make the protein isolate suitable for addition to many different food products.