<u>When making tempera, the content egg yolk is used to bind the power pigment and water (same amount as the yolk). </u>Egg white is not used, and it should be completely removed from the yolk. <u>The ingredients are mixed until the consistency is reached.</u>
As the egg yolk dries fast, usually some fermentation agent (like vinegar) is added in small amounts, to prevent drying and cracking on the painting. The fast-drying prevents the blending or correcting, so the art is done with strokes over strokes.
If stored correctly, paintings done with tempera can last a long, as some from the early centuries are still preserved. Tempera was used a lot during the High Renaissance.
