Frescos cleaned with salad dressing?

Fine art met culinary art in Siena, Italy recently when delicate frescos by Renaissance painter Lorenzo di Pietro were cleaned with a salad-dressing-like mixture of oil and water.

Centuries of grime and wax have been successfully removed using the technique by experts such as physical chemist Piero Baglioni of the the University of Florence. The most recent paintings to be restored are at the 1,000-year-old Santa Maria della Scala in Siena, Italy, one of the oldest hospitals in Europe.