Can you use honey to preserve face masks?
This is a question that I get asked reasonably often. Honey, it is said, is self-preserving. So can you transfer that preserving power into your natural face mask? It sounds like a great idea.
Is Honey Self-Preserving?
This idea seems to be particularly appealing to formulators of natural face masks – though the logic would work for other formats. Unfortunately, it’s not really a goer. Honey cannot be used as a natural preservative. It isn’t even really true that it is self-preserving.
The reality is that humans process it to make it self-preserving. Nature never intended it to be purified and put into jars in your kitchen. If you left it in the hive it would be pretty biodegradable.
How Honey Works As A Natural Preservative
The reason that honey is self-preserving is not that it contains some natural preservative. It’s to do with the fact that it is mainly sugar at such a concentration that it exerts a high osmotic pressure. There are many materials both natural and unnatural that work in the same way.
A sugar solution for example is self-preserving if you get the concentration high enough. But you have to have that high concentration. A strong sugar solution is self-preserving. That’s how jam can be made without a preservative.
When You Can Use Honey As A Natural Preservative
There are circumstances where it is possible to use the osmotic pressure exerted by some ingredients to contribute to the preservation of a cosmetic formulation. It is even possible for this to be the only means of preservation. But this is not often a practical proposition. Getting anywhere near the concentration you need will make your final product way too sticky, and probably unstable too.
The argument is much the same for other natural ingredients such as sorbitol, glycerin and glucose that are often included in formulations as humectants.
Why Honey Is A Poor Choice As A Natural Preservative
And it gets worse. Honey is a very good promoter of bacteria. If you apply it to your skin you are going to give a boost to the bacteria that are already there. For most of us this isn’t too much of a problem. We can generally cope with this kind of thing quite easily.
But it could be an issue for consumers with compromised immune systems. Encouraging bacteria and fungi to grow could be quite unpleasant if you are prone to skin infections.
So if you are using honey at high levels you really need to enhance the preservation of the product.
Honey is not a practical natural preservative. If anything, honey is an ingredient that requires higher levels of preservatives.