Mushrooms have incredible nutritional properties. For one, they pack an interesting protein punch, with many only otherwise found in meat.
This article looks at protein in mushrooms from the perspective of someone on a plant-based diet, particularly vegans, or vegetarians not eating dairy.
The amount of protein in mushrooms contains all nine essential amino acids (EAAs) usually only found in meat. By contrast, most plant-based proteins, are typically missing one or more. Mushrooms also have a high branched-chain amino acid (BCAA) composition, again usually found only in animal sources. This means that mushrooms rival the quality of animal-derived protein, including protein powders.
Scientific research found that the digestibility of mushroom proteins is rated as 'very highly'. That the amino acid content in mushrooms is comparable to that of ovalbumin (egg white) and surpasses soybean and wheat in its bioavailability. This could mean that even though mushrooms contain less protein, that this protein is fully available. Interestingly, the opposite seems true with proteins found in meat substitutes, where bioavailability is low.
In a randomised crossover study looking at the difference in satiety levels between mushrooms and meat, participants expressed significantly less hunger, and a greater sense of fullness, after consuming the mushroom meal.
The not so good
Although extremely high in 'quality' they are low on 'quantity'. You would need to eat about 500g of Oyster mushrooms a day to match just 100g of Tofu! So it is not a practical food for maintaining daily requirements.
100g of mushrooms provides...
Oyster mushrooms 7%
White button mushrooms 6%
Portobello mushrooms 4%
Shiitake mushrooms 4%
By contrast, meat ranges from 55% to 27% depending on the animal.
For those on a plant-based diet, it would be better to choose high-protein plant-based foods like beans and tofu. Then mushrooms to increase the essential proteins not gained from those sources.
100g of the following provides
Kidney bean sprouts 8%
Lima beans 14%
Black beans 18%
Firm tofu 35%
Although a little disappointing in the amount of protein in mushrooms, they are still a nutritional powerhouse. They contain many other nutrients that are difficult to find from plant sources, like vitamin B (with shiitake being a b12 monster) as well as vitamin D amongst others.
Protein profile of Oyster Mushrooms
Oyster mushroom contains a moderate amount of protein, but are still one of the highest compared to other mushrooms - about 2.8 grams per cup. However, the Oyster's provides only 6 of the 9 essential amino acids sufficiently - but is a little low on leucine, lysine and methionine.
The proteins in shiitake are composed of 18 types of amino acids, including 7 of the 8 essential amino acids in a ratio similar to the 'ideal protein' for humans. Of these amino acids, shiitake is especially rich in leucine and lysine, which are deficient in many grains. For people on a vegetarian diet, shiitake represents an excellent protein supplement.
Amino Acid Composition of typical Shiitake
nd = non-detected data expressed as milligrams per gram of crude protein nitrogen.
Further reading about Protein in Mushrooms
Much of this information has been sourced from scientific papers, many of which are listed here.