Food science researchers have managed to whip up a concoction of soy protein isolate, emulsifiers, starches, and other plant-based ingredients to achieve "superior 3D printing performance" of plant-based meat dough. Their secret ingredient seems to have been the use of cocoa butter that finally made the patties flow, while the efforts to 3D-print substitute meat with pea protein have been futile. The researchers added shiitake powder to achieve the taste and say the meat replacement has as much protein as chicken.
https://www.notebookcheck.net/3D-printing-of-plant-based-meat-substitute-made-possible-by-thermosensitive-cocoa-butter.583936.0.html