Preventing Rancidity in Essential Oil Roller Blend
Question
I tried mixing Essential Oil with Grape Seed Oil to make a 10ml Essential Oil roller. Initially, the smell was fine, but after a while, the oil started smelling rancid due to oxidation, changing the scent.
I would like to know if there is a way to fix this or a substance that can be added to prevent the oil from going rancid. I've researched and found that adding Vitamin E is recommended, but I don't know which type or how much to add.
Could you please provide some guidance? Thank you.
Answer
Preventing Rancidity in Essential Oil Roller Blends
It's common for carrier oils like Grape Seed Oil to go rancid over time, especially when mixed with essential oils and exposed to air, light, and heat. Grape Seed Oil is relatively high in polyunsaturated fatty acids, which makes it more susceptible to oxidation compared to more stable oils.
To help prevent this oxidation and extend the shelf life of your roller blend, you can add an antioxidant. Vitamin E is a popular choice for this purpose.
Recommended Vitamin E Types and Usage
There are different forms of Vitamin E available. For protecting oils from rancidity, two common types are:
- Vitamin E (Tocopheryl Acetate): This is a stable form often used in cosmetics. While it's primarily known for skin benefits, it can also offer some antioxidant protection to the oil base. The recommended usage rate as an antioxidant for other oils is as low as 0.01%, but you can use up to 1% in the formula.
- Vitamin E (dl-alpha tocopherol): This form is a more active antioxidant in the oil itself, directly scavenging free radicals that cause rancidity. It is less stable than Tocopheryl Acetate but more effective at preventing the oil from oxidizing. A typical usage rate is 0.1-2%.
For your roller blend, adding either Vitamin E (Tocopheryl Acetate) or Vitamin E (dl-alpha tocopherol) at a concentration of 0.1% to 1% of the total formula volume should help significantly. Start with a lower percentage like 0.1-0.5% and observe the stability.
Other Tips to Prevent Rancidity
Besides adding an antioxidant, consider these practices to prolong the life of your oil blend:
- Storage: Store the roller bottle in a cool, dark place, away from direct sunlight and heat.
- Packaging: Use dark glass bottles, which help block light.
- Minimize Air Exposure: Keep the cap tightly sealed when not in use.
By combining the use of an antioxidant like Vitamin E with proper storage, you can greatly reduce the chances of your Grape Seed Oil blend going rancid and preserve the quality of your essential oil aroma.
Related Products Mentioned
Vitamin E (Tocopheryl Acetate)
Vitamin E (dl-alpha tocopherol)
