Increasingly potato starch manufacturers are recovering this protein as a secondary product. Mostly used as a food ingredient, potato protein can add nutritional value as well as physical functionality, such as foaming, emulsifying and gelation. Use of potato protein also keeps a product vegan and does not need declaration as an allergen.
Finally, we want to mention - as an interesting fact, since the volume used in this application is negligible compared to the other applications - potato proteins can be extracted in functional form: Kemin extracts a specific protein, Proteinase Inhibitor II from Russet Burbank Potatoes. Sold as Slendesta, Proteinase Inhibitor II works by promoting and extending the body’s natural release of cholecystokinin (CCK), a powerful peptide that signals key organs, including the stomach and brain, to induce feelings of fullness.
The Nutritional Value of Potato Protein (2020)Based on Burgos G., Zum Felde T., Andre C., Kubow S. (2020) The Potato and Its Contribution to the Human Diet and Health. In: Campos H., Ortiz O. (eds) The Potato Crop. Springer, Cham
The authors of this content are Gabriela Burgos, Thomas Zum Felde, Christelle Andre, Stan Kubow
Potato protein content is generally low compared with other major staples like maize and beans although potato yields more protein per unit growing area than do cereals (Bamberg and Del Rio 2005).
Also, the quality of the potato protein, which reflects its digestibility and indispensable amino acid content, is very good. The biological value of potato protein—the proportion retained for growth or maintenance divided by the amount absorbed—is high.
Depending on the cultivar, the biological value of potato protein is between 90 and 100 and is very similar to the biological value of whole egg protein (100) and is higher than that of soybeans (84) and legumes (73) (Camire et al. 2009).
The levels of lysine, methionine, threonine, and tryptophan are likely to limit the protein quality of mixed diets consumed by humans. Potatoes exceed the recommended levels of these indispensable amino acids, demonstrating that potato protein is of high quality.
Compared with pasta, white rice, and whole grain cornmeal, potatoes are the only staple food meeting the recommended lysine level. However, sulfur-containing amino acids (methionine + cysteine) are lower in potatoes than in the other common plant staple foods (King and Slavin 2013).