Traces of sesame and moringa have just been found where no one had previously identified them: in paintings from ancient Egypt.
To uncover the artisans’ recipes, researchers collected 28 tiny fragments from 14 works. They date from around 1425 BCE to 400 CE. The collection includes painted coffins, fragments of wall paintings, decorated limestone, and objects associated with mummies, preserved in three European museums.
Sesame seeds.
Pixabay
Color alone is not enough to make paint adhere to its support. Artisans also added materials capable of binding pigments or serving as glue. These are the organic components the team searched for. They analyzed the proteins still present in the samples using mass spectrometry, a method capable of identifying their biological origin.
Animal glues were indeed present, but their composition varied. Cattle predominated in samples containing this type of glue. The analyses also found proteins from sheep or goats, donkeys, and horses. Some clues might even correspond to wild antelopes. The materials used appear to have included hides and other collagen-rich tissues.
The biggest surprise comes from the plants. Sesame and moringa proteins appear in some samples. According to the researchers, these products had never previously been documented in painted works from ancient Egypt.
The works analyzed in this study, along with their museum of origin (M: Medelhavsmuseet; BM: British Museum; NCG: Ny Carlsberg Glyptotek) and inventory number, are classified according to their type of support:
A - wooden coffins (lid and case) and coffin fragments,
B - fragments of wall paintings (earth and plaster support),
C - mummy bust and cartonnage (painted plaster),
D - column capital and relief fragment (painted limestone).
Photo credit: Medelhavsmuseet, © The Trustees of The British Museum, and Ny Carlsberg Glyptotek.
To understand the form in which these plants had been used, the team supplemented the protein study with other chemical analyses. The recovered material was rich in protein and contained only traces of oil. This is more consistent with solid residues obtained after pressing the seeds to extract their oil.
In other words, some artisans may have reused what remained after producing sesame or moringa oil. This interpretation remains a proposal based on several complementary methods. It also raises questions about the availability, cost, or significance of these materials in Egypt at the time.
These findings may also be useful to conservators. Knowing the nature of a glue or binder helps explain how a painted layer may react during conservation. However, the study covers a limited number of objects and nearly 1,800 years: more works will need to be analyzed to determine how widespread these recipes were.