[adrian_b]

Yes, they have replaced the gene used to synthesize the fungus protein that was secreted in the environment with a cow gene or a chicken gene.

So the cow lactoglobulin or chicken ovalbumin produced by the fungus is chemically identical to that from the protein powders that are currently made from cow milk or whey or from chicken egg white.

That means that such fungus-produced protein has an optimal amino acid profile, unlike the natural fungal proteins and if it forms a part of the daily protein intake (e.g. around a third) it can compensate the inadequate amino acid profiles of vegetable proteins.

For about 4 years I have eaten only vegetable proteins, but this created some constraints in what I could eat that were too inconvenient, so eventually I gave up. While now most of my protein intake remains of vegetable origin, I use some whey protein powder in the cooking of certain foods, to enhance their protein content, which has enabled me to make much more varied choices in the menu. Therefore I would know how to use such a product from fungi, if it would become widely available. There are a few startups in this domain, both in USA and in Europe, but for now their target is mostly in selling to big industrial producers of food, not at retail.