Abstract: A process for producing a protein product from plants and yeasts comprises providing a thin stillage or a thin stillage concentrate; separating a protein concentrate from the thin stillage; diluting the protein concentrate to a dry substance content of at most 15 wt.%, tempering the diluted protein concentrate to at least 60° C., and adjusting the pH of the diluted and tempered protein concentrate to alkaline; cooling the processed protein concentrate and subsequently separating a liquid phase; adjusting the pH of the separated liquid phase to an acidic pH, and then separating a solid phase; and dispersing the solid phase in a solvent and subsequently separating a product phase, wherein the product phase comprises the protein product from plants and yeasts.