Otherwise Life

Making a Herbal Infused Oil


So here’s my next post on how I made an infused oil. This was my next project after making a herbal vinegar. I’ve had an interest in herbs and how they can be used medicinally and topically for sometime. If you’re reading this I guess you have too. If you’ve ever been in a health food shop or seen a herbalist, than perhaps making your own is the next step.

In botanical use, herb simply means a herbaceous plant – meaning a plant with no woody stem above ground – rather than just the standard culinary herbs. The list of herbs is numerous. In the UK alone there are 200+.

What is an infused oil?

An oil infusion, or maceration, is a way to extract from plants for topical or culinary uses.

What can I use in an infused oil?

Fresh and dried herbs can be used, even spices, although I will be sticking to herbs for this post.

What oils can I use?

There are quite a lot of oils (called base oils) that can be used that are found in supermarkets. I am using organic extra virgin olive oil. Others that can be used are sunflower oil, rapeseed oil (also known as canola oil) and many others. A list of 26 oils that can be used can be found in Make Your Own Skincare Products by Sally Hornsey. It’s also a great book if you’re a beginner in making your own skincare range.

How to make an infused oil

There are two methods: cold infusion, also called cold-pressed and sun infusion, and hot or hot-pressed infusion. There is no right or wrong for either method, just a matter of personal choice.

The cold method is the long version. For this you will need:

  • A clean, dry jar
  • Herbs, fresh or dried
  • A sunny window-sill or airing cupboard
  • Patience

If your using fresh herbs, chop them up a bit so you can fit in as much as you can. Also this will help with the infusion process. Fill the jar with the herbs and then add your oil to the top. Stir with a glass stirring rod, or skewer, to remove any air bubbles and to make sure everything is covered over. If you’re using fresh herbs, cover with a piece of cloth or kitchen towel and hold in place with a rubber band. This will help the moisture from the plants evaporate out from the jar. Then put on your window-sill or in your airing cupboard. Stir every day, and with fresh herbs push down any that aren’t submerged. This is important as, if left, the herbs will start to mould. Infuse for two weeks.

When it’s ready, strain into a jug. Using fresh herbs will mean that there maybe water in with the oil. This needs to be taken out. Water is a playground for bacteria, so you don’t want your macerated oil to go off. You can either leave it to settle and pour off the oil leaving the water residue behind, or gently heat it (very gently, you’re not looking to boil or simmer) to evaporate the water off (use a bain-marie or double boiler). An article on The Herbarium website says you can put a teaspoon or two of salt at the bottom of the jar, before you put the herbs in, to absorb any water while it’s infusing. You don’t need to do this if you’re using dried herbs as there will be no water residue.

The hot method is done in a double boiler or bain-marie. It’s a faster method that can be done in a day.

Put the herbs and oil in a gently boiling double boiler/bain-marie, so the oil is just covering the herbs. Cover with a tight fitting lid and leave for two hours. Stir every half an hour and check that the water isn’t boiling away. When finished, leave the oil to cool before straining. Other methods for hot infusion include using the oven, or using a slow cooker/crock pot, but I won’t be covering them here. A search engine will bring up lots of those who have tried them.

Strain with a nylon jelly bag or strainer as muslin will absorb the oil.

What is a double infusion?

A double infusion is using one of the above methods, straining the oil, putting a new lot of herbs in the jar or double boiler and covering them with the already infused oil. This garners a stronger infusion. A double infusion is for external use only.

How to store oils

Oils are best stored in blue, green or amber glass bottles or jars, as they will protect the oils from the UV light. If you only have clear glass, store the oils in a cool dark place. Remember to label the bottles with the contents and date that they were decanted.

The infused oils will have a shelf life of about 12 months. Always check the oils before using. If it smells rancid or off, then throw it away.

I hope you have found this useful, and maybe inspired you to make your own. I’ll be doing some more posts soon – a follow up on the herbal vinegar, and how to make an ointment.