Anti-inflammatory and nourishing to the skin, cucumber extract is a useful ingredient for homemade cosmetics. It’s simple to make and provides numerous benefits to the skin.
Cucumber extract is one of my favorite extracts for use in skincare. It’s also the first extract I attempted to make myself.
Why make it?
Cucumber extract is anti-inflammatory and soothes skin. It may also help with dark circles and puffiness around the eyes. Rich in minerals like potassium, it may help firm skin which can help reduce some of the signs of aging.
By making your own cucumber extract, not only can you save money, but you can also ensure the quality of the ingredients being used.
Cucumber extract is quite simple to make and only uses two main ingredients: cucumber and vegetable glycerin. Optionally, you can preserve the finished extract with a natural preservative.
Making the extract is very simple.
First, prepare the cucumber by peeling it and slicing it. While you could probably extract it unpeeled, by peeling it, you are exposing more of the flesh of the cucumber to help speed up the process. (I’m not sure if any of the components of the skin would be extracted and if they would be beneficial. You could experiment with adding some clean peels to a batch to see if you can notice a difference.)
Once you have sliced the cucumber, you can further cut it into smaller pieces that fit well into the container you plan to use for the extraction process. I used a clean glass jar. (Ideally, use one that is clean from the dishwasher, or rinse it, after cleaning it, with very hot water to help sanitize it.)
Add the cucumber pieces to the jar and cover them with vegetable glycerin. It’s a good idea to weigh the amount of glycerin added so that you can later determine how much water from the cucumber has been extracted into the glycerin.
Cover the jar and set it aside for a few days.
The next morning, you should already notice a difference in the way the cucumber pieces look. The cucumber pieces will reduce in size and lose their green color as the glycerin absorbs their moisture. Over the next couple of days, they may begin to shrivel even more.
Because of the amount of water in cucumber, the cucumber extract can be made very quickly. Glycerin is a humectant that effectively absorbs water. Even after only a few hours, the glycerin will be flavored with cucumber. When making other extracts with drier substances like vanilla beans, the process takes much, much longer! Check out my vanilla glycerin extract recipe.
Straining the extract
After a few days, you probably won’t notice any more significant changes in the appearance of the cucumber pieces. At this point, you can strain them out.
Strain the extract by pouring the cucumber mixture through a sieve into a clean jar below. Again, it’s helpful to weigh out the final amount of extract. You can then compare to the original amount of glycerin added to know how much cucumber juice has been infused into the glycerin.
I, personally, don’t press on the cucumber to try to push out any more cucumber juice, but some people do. I allow it to drip dry and then remove the sieve with the cucumber pieces.
Does it need a preservative?
Whether or not homemade extracts need a preservative is a bit controversial.
Glycerin, like alcohol, is a preservative. Unlike cosmetic preservatives sold for cosmetic use, though, it needs to be used in a very high percentage, over 40-50% of the recipe by weight, to safely protect against microbial growth.
To keep things on the safe side, I like to keep the amount of glycerin over 50% of the recipe, by weight. That’s why I suggest weighing the amount of glycerin added and comparing it to the final amount of cucumber extract. It will help give you an idea of the percentage of glycerin in your final extract.
Cucumber extract is edible. If you plan to use it in food recipes, don’t add any other preservatives to it. Instead, keep it in a cool, dry place and try to use it up within a couple of months.
If, on the other hand, you plan on using it solely for cosmetics, it’s a good idea to add a cosmetic preservative to it, just in case. You can add a weaker dose (following the lowest dosage of the recommended range for your preservative) as the glycerin is already doing some preservation. For most cosmetic preservatives, that will probably be around 0.5% by weight, or around half a gram for every 100g of cucumber extract.
To learn more about preservatives, check out my beginner’s guide to natural preservatives.
In case you’re curious, in my last batch, I began with 170g of glycerin and ended up with 237g of cucumber extract.
Cucumber extract can be added to a lot of different types of skin and hair care products. While I normally mostly use it in skincare, I’ve read that it may nourish the hair and even help promote hair growth. So, it may be a great addition to your homemade hair conditioner!
To add it, use cucumber extract in place of part or all of the vegetable glycerin of a recipe. If the recipe you are using doesn’t include any glycerin, you can use it in place of part of the water. Don’t use more than 5% of the recipe by weight. (So, if you are making 100g, don’t use more than 5g.) Over 5%, glycerin can make a product feel “sticky”.
Because your extract isn’t completely glycerin but includes some water too, you could go slightly over 5% in this case. Experiment with it to find the amount that works best for you.
Recipes using cucumber extract
Here on the blog, I used cucumber extract in a couple of recipes.
Because of the cooling effect of cucumber, I decided to add cucumber extract to my homemade after-sun lotion.
After Sun Lotion
Because it is soothing and hydrating and has astringent properties that can help reduce puffy eyes, I also added it to my micellar water recipe. Micellar water is a mild cleanser that can be used with or without rinsing to gently remove makeup.
DIY Micellar water
I also suggested adding cucumber extract in place of the glycerin in the following recipes:
- 1 cucumber
- 175 g glycerin
Prepare the extract
- Clean and peel the cucumber and cut it into slices. Further cut the cucumber slices into smaller pieces that will easily fit into your jar.
- Add the cucumber pieces to a clean jar. Cover the cucumber with vegetable glycerin. (Add enough to fully cover the cucumber pieces.)
- Cover the jar and leave it alone overnight. The next day, shake the jar or open it and stir the cucumbers and glycerin. This helps ensure the cucumber pieces are fully covered in glycerin, which will help prevent microbial (mold, bacteria) growth. At this point, the cucumbers will already have shrunk slightly and the glycerin will begin to take on a cucumber flavor.
Straining the extract
- After a few days, the cucumber won't change much in appearance anymore. At this point, you can strain out the cucumber by pouring the glycerite through a strainer into a clean jar or bottle below.
- Optionally, add a cosmetic preservative to your cucumber extract.
- Cover the jar or bottle, and store in a cool, dry place for up to 6 months.