The true ileal digestibility of amino acids in seitan, tofu, soya milk, and pea emulsion is high and not significantly different among these plant-based foods in minipigs, with values ranging from 92% to 97%, indicating that processing into whole foods does not substantially reduce amino acid bioavailability in this animal model.

When plant proteins are processed into solid foods like tofu, their structure changes in a way that traps some amino acids inside tight clusters, making them harder for digestive enzymes to reach. But even with this trapping, most amino acids remain accessible enough to be broken down and absorbed in the small intestine, so the overall amount absorbed stays high and similar across different plant foods.