Ricotta (literally meaning “recooked”, “refined”) protein can be harvested if the whey is first allowed to become more acidic by additional fermentation (by letting it sit for 12–24 hours at room temperature). Then the acidified whey is heated to near boiling. The combination of low pH and high temperature denatures the protein and causes it to flocculate, forming a fine curd. Once cooled, it is separated by passing the liquid through a fine cloth, leaving the curd behind.