Cultivation and uses
Egg tempera was the paint used by virtually all artists during the Middle Ages. In fact, the use of tempera paint can be traced back to ancient Egypt. In the early Renaissance, artists used egg yolk as a binding agent, mixing in colored pigments to create egg tempera paint. Egg tempera had its limitations. It could not be stored, so each color was mixed when it was needed. Mixing too little paint was a disaster because mixing additional paint to match the first batch perfectly was very difficult. Mixing too much paint was a waste of expensive materials. Because egg tempera dries very quickly, artists had to paint small areas at one time. The fast drying time made blending one color into another difficult, so artists layered one color over another dry color to create modeling; a way to give three-dimensionality to forms by shading or blending.