Using a unique technique to analyze the smells of Egyptian mummies, scientists have discovered amazing information about the evolution of mummification methods throughout the ages, and have been able to distinguish between different body parts based solely on their smell.
Thousands of years ago, the ancient Egyptians developed the art of mummification to preserve the bodies of their dead. Initially, bodies were buried in hot sand to dry naturally, but as Egyptian civilization developed, deliberate mummification using special materials emerged, and this tradition continued for more than two thousand years.
The materials used in mummification varied and included vegetable oils, animal fats, beeswax, and resins (gummy substances extracted from trees). Each of these materials has a unique chemical signature that can be identified through laboratory analysis.
Scientists typically need to cut pieces of shrouds or tissues and analyze them chemically using complex and time-consuming methods. But researcher Wangyu Zhao and her team at the University of Bristol thought differently: what if they analyzed the smells emanating from the mummies themselves?
"We noticed that anyone who gets close to the mummies is struck by the intensity of their smell," says Chao. "This smell is not fleeting, and it makes sense that it would be related to embalming materials. We thought that instead of replacing traditional methods, why not use smells as an additional way to decipher ancient embalming practices?"
The team selected 35 samples from 19 mummies dating from 2000 BC to 295 AD, a period that roughly represents the golden age of mummification in ancient Egypt.
The samples were placed in a sealed chamber to release their volatile organic compounds (the odor molecules that rise from the materials), and then these gases were analyzed using precise techniques to separate and identify their components.
The analysis revealed that embalming recipes were not fixed, but rather evolved and became more complex over the ages:
Initially (the pre-dynastic and Old Kingdom periods), the Egyptians used simple recipes that relied almost exclusively on fats and oils.
In later periods (the Neolithic, Ptolemaic and Greco-Roman periods), the recipes became more complex and began to include beeswax, conifer resins and tar.
One of the most surprising results was that samples containing 100% fats and oils showed an abundance of aromatic compounds, which is unexpected because these compounds usually appear in small amounts in traditional analyses.
"These aromatic compounds may be from plant embalming materials, but they could also come from shrouds or even the wood used in coffins," explains Chao. "We cannot confirm a single source yet."
Interestingly, scientists have found clear differences in smells between different body parts, even in mummies from the same time period.
Chao explains: "This difference may reflect different, deliberate treatments. Perhaps the ancient Egyptians used different embalming materials for each organ for practical or religious reasons. Also, preservation conditions vary from organ to organ, as the type of tissue and its degree of decomposition affect how it retains and releases odors. This is an area that deserves further research."
Zhao hopes to expand the study in the future to include mummies from other geographic regions and time periods. She says, "With more diverse samples, we can develop a comprehensive view of the factors influencing scent signatures, such as regional mummification practices, temporal changes, and even the age or sex of the mummies. We may also be able to identify volatile biomarkers that help distinguish between different geographic origins or time periods."
The study, published in the Journal of Archaeological Science, opens the door to a new era of non-destructive archaeological research, where scents can tell stories about the past that would not have come to light through traditional methods.
