Important factors must be considered when choosing which black seed oil to buy are listed below.
1. Slow Cold Pressed
This means no heat is used in the extraction. Nigella Sativa seed oil contains many different components. The unique mix of compounds work together to provide the healing properties. Using heat during the extraction causes some of the more volatile compounds to evaporate [1] diminishing the quality of the oil. Ideally the pressing should also be done slowly as a fast pressing will itself generate heat up to 80 degrees celsius – this gives a dark red coloured oil and a bitter taste.
2. Totally Pure
This speaks for itself. When you pay for black seed oil you expect to get black seed oil. Pure means 100% pressed oil of the Nigella Sativia seeds, completely free from any additive. Any ‘black seed oil’ bulked out with any other oils must be avoided.
3. Chemical Free Extraction
Avoid any oil which uses chemicals in the extraction process. Adding chemicals such as benzene derivatives can help to extract more oil from each batch of seeds however will inevitably result in a contaminated product.
4. Bottled in UV Filtering Glass
Glass bottles are completely inert and will preserve the oils natural integrity much better. Additionally some cheap plastic bottles leach chemicals into the oil over time. Glass is also friendlier to the environment!
5. Unfiltered / Unrefined
The whole Nigella Sativa seed contains different healing compounds (e.g. the seed skin is packed with large amounts of Nigellone) in order to increase the mix of these valuable components in the oil use an unfiltered unrefined oil.
6. Origin
The climatic and soil conditions in which the Nigella Sativa plant is grown impacts on the quality of the seed and hence the taste of the oil. The best climatic conditions for any flowering crop is one in which the days are hot and the nights cool, it is for this reason Turkish black seeds are renowned as the best in the world.