In the July Q&A on Patreon, Belinda asked: I have two questions...1) do you know if polyquaternium 10 has an expiration date? I've checked the website I bought it from (Personal Formulator) plus a couple more that sell it, and I've not seen anywhere if it does, indeed, expire. The reason I ask is because I'm having problems getting it to dissolve in my water phase, and I was wondering if the reason was that it's not "fresh". 2) Is acetic acid and aspen bark extract a good preservative system for hair conditioner? I've seen this listed on a product being sold on Etsy, and I have not found any evidence to back up the fact that this is a good preservation for a conditioner. I told my friend she should throw it out, but am now wondering if I was over-reacting.
The quick answer to the first question about polyquaternium 10 is that everything has an expiry date at some point, so we just have to find it. This version has a shelf life of a year, as does this one. So I'd say a year? Which sucks because I have some that I've had a lot longer than I thought!
Acetic acid (aka ethanoic acid) is the acid found in vinegar. In this post (scroll down to Edina), Perry Romanowski says he doesn't think dehydrated acetic acid will work as a preservative, and he says it again in this post. I've seen variations on acetic acid in preservatives, like dehydroacetic acid like we find in Optiphen ND, but never just acetic acid. Could this person be using vinegar - probably apple cider vinegar - in their products?
Oh, wait, I wonder if it's being used as apple cider vinegar in a conditioner as people like to use that in their hair? (See this post I wrote about it here...)
As of today, I can't find anything about this being used as a preservative on its own and I couldn't find any company selling a preservative that contains it. If you have any information, my lovely readers, please let me know.
I've written about this a bit as an ingredient found in Natapres. The Populus Tremuloides Bark Extract comes from the quaking or trembling aspen, and it's listed as an anti-bacterial. It seems like it would need something to go along with it to make it a broad spectrum preservative, like one of the organic acids as a fungicide, like potassium sorbate or sodium benzoate.
My humble opinion is that I wouldn't trust those ingredients to preserve a hair conditioner or any other water containing product as they aren't part of a broad spectrum preservative.
Yeah, I know that's willow bark extract in the picture, but I needed something to break up the wall of text, and this was the closest I could get.
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