Cold – yes, in air – no!
Especially when pure, essential oils are not cheap, so they need to be good for use as long as possible. In the refrigerator, they double their shelf life.
Over time, most components of essential oils are oxidized, and heat favors this process. Once it’s started, it’s tough to stop, although it’s pretty slow – it’s been months. Do not worry if you’ve forgotten the vials in the sun car for a few hours – they will still be good to use. The sudden change of temperature is also not such a problem, as long as they are well-chilled most of the time.
The ideal temperature
0-3 ° C – the temperature of most refrigerators is the best for most essential oils. Keeping them in the freezer is also good, but additional cooling below the quoted degrees will not add many benefits. Here’s what you should be careful about:
- If you keep them in your refrigerator for everyday needs, some of the food can get the flavor of the essential oils. So place them first in a container – a wooden, plastic box, or a cosmetic cleaner. If you have a large collection of oils – or plan to have – it is best to have a refrigerator specially designed for this purpose.
- The more chilled they are, the higher their viscosity (they become thicker and sticky). In most cases, this will not make much difference, except that they will be pounding more slowly. Especially, the rose oil will harden – if you have bought an undiluted, pure rose oil and it does not harden in the refrigerator, it is not real. If you want to warm up some chilled essential oil, you only need to hold the bottle in your hand for a minute.
How do you know that essential oil has oxidized?
- It will not smell as fresh as in the beginning. You may not notice, as change is slow, but if you compare it with just bought, you will feel the difference.
- Citric oils sometimes get cloudy. If this happens, let the sludge reach the bottom of the bottle – this may take several hours. Then, with a clean pipette, transfer the nice part of the oil into another bottle and discard the rest.
- Do not rely on shop testers as a way to smell fresh essential oil. These testers are constantly opened and exposed to the corrosive effect of air – most of them have probably already begun to oxidize. (Those that are for sale are still reliable as they are sealed).
Especially prone to oxidation are citrus fruits that are rich in lemon. While oxidizing, the percentage of pure lemon in lemon oil decreases significantly because it is converted to other substances. The consequences of this are two:
- Since lemon oil no longer contains lemon, it no longer has the effect that is supposed to be. In other words, its therapeutic power is decreasing.
- The chemicals that are formed – mostly citric oxide and peroxide – are not very pleasant, they are not curative and increase the sensitivity of the skin to lemon oil. The risk of an allergic reaction is small, but it is not negligible.
What is the shelf life of essential oils?
Depending on when you start counting. If you take the point at which it was extracted (distillation) as a starting point, you need to know when exactly this happened – and in most cases, you do not have such information. So, run the stopwatch when you open the bottle. Here’s how long the different essential oils will last if stored in a refrigerator:
- Citruses, neroli, lemongrass, incense, tea tree, white pine, and spruce: 1-2 years
- Sandalwood, vetiver, patchouli: 4-8 years old
- All others: 2-3 years
If you do not store them in the refrigerator, cut down the above figures.
- Instead of discarding old oils, you can add them to household cleaning products – especially those from citrus fruits.
- For long-term storage, keep undiluted oils in glass containers.
- Always put the cap when not using the oil.
- Essential oils are inflammable – do not keep them near electric appliances, fireplaces,
- If you have small children, store them in inaccessible places – absorbing them is dangerous.