Thursday, August 7, 2014

Vitamin E is NOT a preservative and you don't have to add a preservative to an anhydrous product

Vitamin E is not a preservative. It is an anti-oxidant. An anti-oxidant will slow down the rancidity of your oils. A preservative prevents the contamination of your product by things like bacteria, yeast, or mold. Vitamin E will not prevent contamination of your products, but it will retard the rancidity of the oils in your products.

Related posts:
A review of rancidity and anti-oxidants
A more in-depth look at anti-oxidants

You do not need to add a preservative to a product that doesn't contain water (anhydrous products) unless it will come in contact with water. (Something that you'll take into the bath or shower with you will come into contact with water, so you will need a preservative for those products.) You can add an anti-oxidant to the product to retard the rancidity of the oils, but you don't need a preservative in something like a whipped butter or balm.

Related posts:
Preservatives - a whole bunch of posts on the topic
Why use a preservative?
Mechanisms of rancidity
Storing products in the fridge
If you really want to make products without preservatives...
The importance of preservatives

If you have something like a dry face mask that will only have water added to it once, when someone is using it, you do not need to add a preservative or an anti-oxidant to the product because it doesn't contain water and it doesn't contain oils. If you have something like a sugar scrub bar that you will take into the shower, you will want to add a preservative. If it is a one-time usage product, you don't need to add a preservative as it will not grow beasties until the water is added.

To summarize: 
Anti-oxidants retard the rancidity of your oils.
Preservatives prevent contamination.
You need to use a preservative in a product that contains water or will be around water.
You don't need to use a preservative in an anhydrous or non-water containing product.
You can use anti-oxidants wherever you are using oils.


Randy Schueller said...

Hi Susan. I love your articles! One point of clarification though: wouldn't you want a preservative in an anhydrous product to protect it from contamination during use? I'm thinking of moist, dirty fingers digging into a tub of whipped butter.


Susan Barclay-Nichols said...

Hi Randy. You can put one in if you want, but beasties require water to grow, and we aren't getting water into those products, the beasties won't grow!

Juli R. said...

Hi Susan,

I've read through most (if not all) of your posts on preservatives. I still find myself asking a question, though. If I make a face mask using shea butter, a carrier oil, a variety of dry clays, soy powder, fruit extract, vitamin E and essential oils, what kind of a preservative do I use? I have Liquid Germall Plus but not sure if it would work in this case as I'm not adding water (but water could potentially be introduced).

As of now, I'm planning on selling dry mask powders with a bottle of "wet ingredients" (oils, glycerine, etc), but I would love to have ready-made masks as well.

PS. Your blog is one of the best resources out there!



timmie sue said...

I'm a newbie and have one nagging issue. I am currently using a commercial anhydrous base (all natural) which does have preservative (several, I think from my research). I am using 4 parts base and one part witch hazel that I have gathered from your blog is classified as water. My question....Is there enough preservative in my base to carry the extra liquid or should I preserve the liquid before adding.
Timmie Sue