From improving the taste of food to their invaluable application in medicine, oils seem to have been a part of human history since eons. It is difficult to trace the exact point in time when man discovered the wonders of oil and how to extract it. Nonetheless, there are some theories and archaeological discoveries that can help us paint a picture.
Animals have always known how to use elements in their surroundings to their advantage. For instance, pregnant female lemurs in Madagascar chew on fig and tamarind leaves and bark to kill parasites, increase milk production as well as increase the chances of a successful birth.
As humans evolved, they took it a step further and began using tools to obtain specific extracts (e.g. juice, sap, oil) from different parts of a plant. However, oil extraction didn’t happen until the development of more advanced ancient communities.
After man learned to use fire, the first form of oil he probably discovered was animal fat. As it cooked over a fire, the meat would release a greasy substance.
Despite the invention of the mortar and pestle in the Stone Age, it wasn’t until much later that he deliberately extracted plant oils with it.
In his book, Ghani: The Traditional Oilmill of India, Dr Acharya says that early man did not extract oils from vegetables. At the most, they crushed mahua seeds using adhoc arrangements of logs, similar to what some Indian tribes practise till date. Nomadic communities used animal fats like ghee, which were convenient to prepare using easy-to-carry utensils like butter churns. The earliest evidence of vegetable oil was probably from seeds boiled to obtain oil.
When a sizable community of farmers was formed, people realised that they could cultivate seeds like sesame and grind them to obtain their oil. Evidence of this can be seen from the charred remains of sesame seeds that were obtained from the Harappan civilization (circa 2000 BC). Seeds were first crushed in a mortar and pestle then boiled to extract the oil. At the time, oils were used for culinary purposes.
The Rigveda (circa 1500 BC) mentions the use of a mortar and pestle device (ulūkhala) or grinding stones (grāvan) to crush soma. Large stone mortars used as oilmills and dating back to 100 AD to 200 AD were found in Dwaraka, Gujarat.
The traditional ghani
From the large stone oil mills came the ghani—a wooden mechanical oil-press system powered by animals. It consists of a large mortar and pestle. The large bowl-like mortar has a smaller wooden vessel container where seeds are placed. It may have a hole to drain the oil, though some collect the pure oil that floats on top with no need of filtration. The animal is tied to the pestle. As it moves in a rotating motion, the force exerted by the pestle releases oil from the seeds.
Today, the use of ghani is limited to rural areas.
Essential oils are extracted from various parts of a plant. They are volatile aromatic oils that possess intrinsic healing and antimicrobial properties.
In India, their recorded use in Ayurveda goes back as far as 1500 BC. They were largely used along with carrier oils like coconut or sesame oil in medicinal concoctions. These concoctions were then used as laxatives, emetics, antibiotics, anti-inflammatories or for therapeutic massages.
Thus, the history of the extraction and use of plant oils in India is as rich and old as our ancient civilization. It can be traced back to 5000 years ago.
To this day, many Indian tribes still carry on with these indigenous practices. They appear to live long, sustainable, healthy and happy lives despite not having access to modern medicinal facilities.