Beer and eggs are commonly seen in the kitchen. However, scientists recently found that they were used in historic paintings, too.
To keep Danish (丹麦的) paintings, a group of researchers studied what ancient paint was made of. They did experiments on small pieces of paintings that had already been cut off from the original(原始的) artwork
According to their research, grains and yeast (酵母) were found on the base of the paintings.
Beer was the most common drink in the 19th century in Denmark, and its by-products were spent grains and yeast.
The study showed that they were used to provide a stable (稳定的) painting surface. Researchers also pointed out that beer by-product was used as a "glue" because it had a lot of sugar. With beer added, the paint can also dry faster.
Besides beer, egg has long been found in oil-based paints used by artists in the 15th century, such as Italian painter Leonardo da Vinci. A recent study published in Nature Communications may have "cracked the secret of how eggs can help keep artworks.
The researchers re-created the ancient paint by adding egg yolks (蛋黄) to oil paint. They then looked into how it changed over time. The findings showed that the yolk's proteins helped slow the oxidation (氧化) of the paint. They could also make the paint smoother.
However, the oil pant with added egg usually takes longer to dry. It seemed fine for artists -they were willing to accept to have their work kept for longer.
"The more we understand how artists chose and used their materials, the more we can realize what they were dong", Ken Sutherland, an expert at the Art Institute of Chicago, US, told Science News. Sutherland added that research like this could help people have a deeper understanding of the artworks.
