How long do oils last?
While we do our best to ensure that our oils have a best before date on the label, this date is just a guideline. Here is a little more information about the longevity of oils.
The shelf life of an essential oil or carrier oil can vary dramatically, depending on the chemical stability of the oil. Unlike the food we eat which can have a more predictable timeframe, it is extremely difficult to predict the point at which and essential oil or carrier oil is going to go off. It is dependent so many variables and there are a large number of external factors that can cause the oxidization that leads to degradation. For example air, direct sunlight or heat. This is why correct storage is so important and it is recommended that oils are stored in an airtight, dark coloured bottle, in a cool place where there is minimal temperature fluctuation, away from sunlight. Preferably full so there is a minimal amount of air inside.
However, as every single essential oil has it’s own unique chemical composition with it’s own rate of deterioration, making it hard to pin point when the oil will go off, even under perfect storage conditions. Some oils may last far beyond the recommended best before date, while others, if stored improperly, may deteriorate earlier.
Carrier oils do not last as long as essential oils and will go rancid. Vitamin E or Rosemary extract are antioxidants can be added to help to prolong shelf life. Although essential oils do not go rancid, they slowly degrade, and the colour, texture and odour is the easiest way to tell if an oil is still suitable for use. If the oil is thicker, darker or no longer smells like it should, it is safe to assume it is no longer usable. Trust your nose.