Need help figuring out solubiliser amount

[Dreamer]

Hey Everyone,
I am looking to make a body spray with essential oils. I am having trouble figuring out how much solubiliser I should be using. So, for example, if I was making a spray that was 98% water and 2% EOs, about how much solubiliser would I be adding as far as %? I realize that different EOs require different amount of solubiliser, but generally speaking, when the solubiliser's suggested use rate is stated to be .5-10%, what is that a % of? Is it % of total formula amount or of the water or of the EOs? Also, has anyone made an EO/water combination using a solubiliser? If so, which solubiliser did you use? I am looking to stay within ecocert or COSMOS standards. Thank you for any input/help.

 

[atiz]

I don't really have a precise formula for these kinds of things so maybe someone more knowledgeable will come around. But I tend to use either Polysorbate 80 or 20, and just see how much I need to dissolve the oils in the water. I think most of the time the amount tends to be similar to the oil amount.
I'd think .5--10% is of the whole batch; certainly not of the EO.

 

[DeeAnna]

There is no set answer, because the result depends on the interaction of all chemicals involved as well as temperature of the mixture. It's really something you have to figure out by trial and error.

I normally use Polysorbate 80 -- I know PS 20 is supposed to be "best" but I have not had as good results with it as I have with PS 80. But try PS 20 if you like -- there's nothing wrong with using PS 20 if it gives you the results you want.

I gather that some people recommend mixing the EOs with the PS first and then adding the solvent (aka the water or vodka), but I don't normally bother with that when testing -- it's too cumbersome. You can follow this rule for the final product, if you feel it's best.

Calculate the PS weight based on the weight of EOs, not on the weight of the whole mixture.

Start with equal weights of PS and EO -- in other words, a 1:1 ratio of PS-to-EO by weight. Mix well with the solvent and let sit. It's usually milky colored at first. If it's going to fully solubilize, the mixture will clear within, oh, 12-24 hours. Sometimes sooner.

If a 1:1 mixture doesn't give a clear mixture, add an additional amount of PS equal to the original weight of PS. That will create a 2:1 ratio of PS:EO in the mixture. The mixture may clear or it may stay milky. If milky, give it some time to stabilize. Evaluate and increase the ratio to 3:1 if needed, and so on. I typically expect to get a clear mixture at 3:1 to 6:1 ratio of PS:EO, but sometimes I need more, sometimes less.

The ideal ratio of PS:EO is the least amount of PS that gives you a stable, clear mixture within the range of temperatures that you expect the mixture will see. The mixture may cloud when it cools too much; in that case, more PS is required to keep the mixture clear at the cooler temps.

 

[Dreamer]

Thank you, atiz and DeeAnna, I appreciate your input. DeeAnna, that was a very informative post! I have a much better idea how to work with a solubiliser now. The only thing I will need to do is find one that is ecocert since I don't believe that Polysorbate is. Thank you again.

 

[SaltedFig]

... The only thing I will need to do is find one that is ecocert since I don't believe that Polysorbate is. ...

Hi Dreamer,

This COSMOS resource is a searchable list that includes the EXOCERT approved ingredients: http://www.cosmos-standard-rm.org/verifmp.php

This blog compares three natural solubilisers (for use with EO/aqueous blends), so might be of some interest to you - it describes the amounts and how to combine them, with comparative pictures and descriptions of the results: https://skinchakra.eu/blog/archives/371-Natural-Solubilisers-in-Comparison.html

(And no, polysorbate is not on the COSMOS list )

 

[Dreamer]

Hi Dreamer,

This COSMOS resource is a searchable list that includes the EXOCERT approved ingredients: http://www.cosmos-standard-rm.org/verifmp.php

This blog compares three natural solubilisers (for use with EO/aqueous blends), so might be of some interest to you - it describes the amounts and how to combine them, with comparative pictures and descriptions of the results: https://skinchakra.eu/blog/archives/371-Natural-Solubilisers-in-Comparison.html

(And no, polysorbate is not on the COSMOS list )

Thank you for those links, SF, they're appreciated! Looking into the one about the 3 solubilisers, and checking the prices, wow, using any of those solubilisers in an EO/H2O formula adds a lot of expense! This has all been rather eye-opening. Thanks!

 

[DeeAnna]

I agree. If you're looking for a crystal clear product, it can take quite a bit of solubilizer to reach that goal and that definitely adds to the cost. It might be more cost effective and just as useful to develop a light emulsified lotion instead. I realize a lotion is not always a suitable option -- as in the case of an air freshener or cooling "spritz" body spray -- but it's worth keeping in mind.

 

[justjacqui]

If you are happy to include ethyl alcohol (ethanol) at around 10% this will usually help to reduce the amount of solubiliser needed. If you have a lot of solubiliser you might find that it is sticky depending on what solubiliser you use.

 

[DeeAnna]

I've often used 80 proof vodka (40% ethanol by volume) and unfortunately have still had to use quite a bit of solubilizer to get a clear result. I guess this is another "your mileage may vary" kind of situation.

You make a good point @justjacqui -- solubilizer can be sticky at higher amounts.

 

[atiz]

Yes, I have also experienced stickiness. I don't always aim at crystal clear; just shake the bottle before I use it. Maybe not ideal but for personal use I like it more this way than having so much solubilizer in the spray.
(My parents once had a 160 proof absinthe; yeah, that helped a bit. But won't be trying to get one around here.)

 

[Dreamer]

I agree. If you're looking for a crystal clear product, it can take quite a bit of solubilizer to reach that goal and that definitely adds to the cost. It might be more cost effective and just as useful to develop a light emulsified lotion instead. I realize a lotion is not always a suitable option -- as in the case of an air freshener or cooling "spritz" body spray -- but it's worth keeping in mind.

Hmmm, that is an interesting idea - I will keep that in mind.

 

[Dreamer]

If you are happy to include ethyl alcohol (ethanol) at around 10% this will usually help to reduce the amount of solubiliser needed. If you have a lot of solubiliser you might find that it is sticky depending on what solubiliser you use.

Thanks, justjacqui, I am beginning to think it is time to think away from a solubilisers. They really aren't cost-effective.