Tuesday, August 20, 2013

Tuesday Wonderings: Is glyceryl stearate an all-in-one emulsifier? If not, what can I do with it?

In this post, You don't need to use the HLB system for all-in-one emulsifiers, Nicole asks: Can you help me out with a 'self emulsifying wax' I purchased which is listed as Glyceryl Stearate & Potassium Stearate (MSDS < 96 Glyceryl Stearate, < 7 Glycerine, < 3 Postassium Stearate). I thought his was an all in one self emulsifying wax, but it appears it is not. I suspect it is Glyceryl Stearate SE which suggests is best used as a thickener of lotions. Any suggestions on type of product I might be able to make with this? Even suggested usage rates would be helpful and will research possible formulas. I have emailed the company I purchased this from, but given they sold this to me as an 'all in one', I'm not expecting too much from their response. I was thinking I may be able to use this to thicken a water based foaming face cleanser which I will send a separate note on.

This is one of the reasons I suggest that when it comes to emulsifiers, we need to check what we have! This isn't an all in one emulsifier. Glyceryl stearate is a low HLB emulsifier (2.9) that has to be combined with a high HLB emulsifier, something like ceteareth-20 or one of the polysorbates, for example, to create an HLB system or all in one emulsifier. (I've written a post on it, which you can find here.) Here's an example of how to create an HLB emulsifier with the glyceryl stearate, but you could use any of the other examples in the HLB series to which I link below and substitute glyceryl stearate and your other emulsifier and do the math for it.

Glyceryl stearate isn't the same as glycol distearate, so you can't use it in a foaming facial cleanser as an emollient and thickener, unless you're making an emulsified product with another HLB emulsifier. You can use it in lotions as a thickener, the way you'd use stearic acid or cetyl alcohol.

What could you make with it? Use it as an HLB emulsifier or a thickener. You could use it in something that is intended as a foot product - I like this foot lotion recipe, and you could remove 3% of the butter and replace it with glyceryl stearate, or this foot cream and replace the cetyl alcohol with glyceryl stearate - or you could use it in something you want to be a stiff cream. You could use it in something like this foot scrub bar as well.

As an aside, I wouldn't trust a supplier that couldn't give me information or wouldn't respond to my e-mails. A big part of choosing a supplier is choosing someone who supports and knows about their ingredients. If they can't be bothered doing that, I wouldn't be ordering from them again. Just my two cents...

Related posts:
HLB system - an introduction (start of a series)

15 comments:

Anonymous said...

Actually, glyceryl stearate SE is often a mix of glyceryl stearate and potassium stearate that is self emulsifying. For some reason, the potassium stearate is rarely mentioned on the INCI.
Glyceryl stearate by itself is a pretty nice co emulsifier.
Lalla,

Nicole said...

Thanks so much Susan for your response. My plan is to use it as a co emulsifier. I'll let you know how I go! Kind regards, Nicole

jbarber said...

I love to use glyceryl stearate (not the SE version) with either cetearyl glucoside or peg100-stearate or cetearth-20 as per the HLB system. Seems to work well. By the way, the glyceryl stearate smells great too!

Susan Barclay-Nichols said...

HI Lalla. What's your experience using this emulsifier? What do you think? I've used glyceryl stearate with ceteareth-20 for a really nice feeling lotion, but I'm curious what it is like on its own.

Hi Nicole! I can't wait to hear what you think!

Hi jbarber! What does it smell like?

Annalisa said...

Hello Susan!
Thanks for this great blog.
I would like to try a water-in-oil emulsion for very dry skin. Would it be ok to use only glyceryl stearate (HLB 3.8 according to the supplier) as emulsifier?
What should I do about the HLB system then? What I mean is: if I use 30-40% vegetable oils with required HLB of about 7, should I then use a combination of emulsifiers with HLB 7? Though, wouldn't that be an O/W emulsion instead of W/O?
Thanks also to anyone else that would like to reply
Annalisa

Susan Barclay-Nichols said...

Hi Annalisa. If you are using less than 50% oil, then it is always an oil-in-water lotion. Almost all of the lotions we make are O/W lotions. (Cold cream is a water-in-oil lotion.)

I'm not sure if you've seen it, but there's a whole section on the blog devoted to skin chemistry with a large section on dry skin. If you make an oil-in-water lotion, you can add all kinds of lovely things like humectants and conditioners and extracts and things other than oils to help with your dry skin. I don't know if a W/O the best choice for dry skin when you could be using all these other water soluble ingredients? Just curious why you want to make a water-in-oil lotion instead?

As I mention in the post, glyceryl stearate on its own will not work as an emulsifier. You have to combine it with a high HLB emulsifier to get to the number your lotion requires. You mention it is 7, so you'll want to use a high HLB emulsifier in the right ratio to get the emulsifier to be 7. Check out the section of the blog devoted to the HLB system to learn more.

Annalisa said...

Hi Susan,
thanks for taking the time to reply!
The reason why I wanted to do a W/O is simply because I've already done plenty of O/W emulsions for my self and friends, and now I wanted to try something new, but a bit more "professional" than a cold cream for a friend with really dry skin (legs).
I based my question on the info I found in this article

http://www.makingcosmetics.com/articles/27-how-to-make-water-in-oil-emulsions.pdf

I quote: "Although most moisturizers (incl. day and night creams) are O/W emulsions, a W/O emulsion is preferred if the product is intended for very dry, sensitive and compromised skin"

and

" As a rule of thumb, the amount of water is always approximately 60 - 80 %. So, what is it that determines whether you have a O/W or W/O emulsion? - It is the type of emulsifier that determines the type of emulsion"

(this is why I thought of 60-70% water also in W/O)

I am still confused about the HLB system in case of W/O. If I use more than 50% oils as you suggest would I still need to consider the HLB? I only use vegetable oils that usually have a required HLB of 7-8, and for W/O emulsions I would use mostly a lipophilic emulsifier, so how would it be possible to match the required HLB?
...I hope my question makes sense, and thanks again!!

Annalisa

Marina said...

Hi everyone!

I know it seems that glyceryl stearate cannot be used by itself, but I think there are some examples of lotions that only use glyceryl stearate citrate as an emulsifier, or a combination of glyceryl stearate and glyceryl stearate citrate.

For example: my favorite store-bought lotion is Bach's Rescue Cream. The only emulsifier in this lotion/cream is glyceryl stearate citrate. It has beeswax, xanthan gum, and cetearyl alcohol as thickeners.

A popular lotion in New Mexico is Marsha Mason's Healing Body Butter. It has glyceryl stearate and glyceryl stearate citrate as emulsifiers and cetyl alcohol as a thickener.

I believe the way glyceryl stearate citrate is made is by taking glyceryl sterate and mixing in citric acid. I think it's that simple. Someone correct me if I'm wrong.

According to some online sources, glyceryl sterate has an HLB of about 5.8, while glyceryl sterate citrate has an HLB of 10-12. So, I think some people recommend mixing some citric acid into your glyceryl stearate lotion to give it a higher HLB. If you are using cetyl alcohol (required HLB = 15.5) or cetearyl alcohol (required HLB = 15.5), these will require a higher than 5.8 HLB emulsifier.

So, maybe try adding some citric acid to your glyceryl stearate lotion to help keep it emulsified. How much? I am not sure.

Also, try using oils/butters like fractionated coconut oil (required HLB = 6) and cocoa butter (required HLB = 6), as these match the HLB of glyceryl stearate (HLB = ~5.8).

Also try using Xanthan Gum (in the water phase) rather than cetyl alcohol, cetearyl alcohol, or stearic acid because these alcohols and and acids increase the required HLB.

I recently made a lotion:

73% water
0.5% Xanthan Gum
15% Fractionated Coconut Oil
5% Cocoa Butter
4% Glyceryl Stearate
3% Leucidal Liquid

and it turned out great! This lotion is very simple, but feels and looks great - not too heavy, not too watery. I don't know if it will eventually separate, but I will keep you posted. If it does separate, I will add some citric acid and see what happens.

Good luck!

Susan Barclay-Nichols said...

Hi Marina. When using glyceryl stearate with glyceryl stearate citrate, you're creating an all-in-one emulsifier using the HLB system, so you aren't using glyceryl stearate alone. You've demonstrated this with the products you've quoted as they all have two emulsifiers that have been brought together through the HLB system.

You can have an HLB of 5.8 for glyceryl stearate, but this doesn't mean that glyceryl stearate alone will emulsify something with a value of 5.8. It means that this is value glyceryl stearate has on its own and it must be combined with another emulsifier to create the HLB emulsifier. To emulsify the butters you mention with ratings of 6, you would have to combine glyceryl stearate and something else to come up with a number that is close to 6. This means you won't have 100% glyceryl stearate. Even if you had something with an HLB of 5.8, it won't emulsify it alone.

For more information about the HLB system, click here for the start of the series.

I honestly don't think it's as easy as adding citric acid to your product as there's going to be a chemical reaction to create glyceryl stearate citrate, something I don't think can be attained in our workshops by adding citric acid to a product. Adding citric acid will reduce the pH, however, so it's not to be done without access to a, accurate pH measuring device.

As an aside, I looked up the Bach's Rescue Cream, and it contains an emulsifier combination of PEG-100 stearate and glyceryl monostearate, which we can buy as Lotionpro 165.

I'm not sure what product you're quoting as this is the ingredient list I found on their page: Purified water, Cetostearyl alcohol, Apricot kernel oil, Coca seed butter, Glycerin, Cetyl palmitate, Glyceryl, Glyceryl monosterate, PEG-100 stearate, Caprylyl glycol, Phenoxyethanol, PEG-20 stearate, Glyceryl caprylate, Benzyl alcohol.

If you're referring to the balm, it's anhydrous and doesn't need an emulsification system.

Marina said...

Hi Susan! Thank you for the heads up on the difference between glyceryl stearate and glyceryl sterate citrate. There is one company in Australia that sells glyceryl stearate citrate (shop.newdirections.com.au). I cannot find it anywhere in the U.S. I think I will purchase it and combine it with the glyceryl stearate SE and see how it goes.

An update from 2 weeks ago: the lotion with glyceryl stearate SE has still not separated (after almost 4 weeks). Note: I wrote that I made it with glyceryl stearate, but it was actually glyceryl stearate SE.

Thanks for the list of ingredients for the Bach rescue cream. I think they completely changed the formula! The bottle I have at home (which I purchased 3 weeks ago) lists:

Ingredients: Beeswax, Caprylic/capric triglyceride, caprylyl glycol, cetearyl alcohol, cetyl palmitate, citric acid, glycerin, glyceryl stearate citrate, isopropyl palmitate, potassium sorbate, purified water, shea butter, xanthan gum.

Some issues: They listed ingredients in alphabetical order instead of in order of highest to lowest concentration. (What's up with that?) Also, they don't have any preservative except potassium sorbate. This seems a little sketchy to me. Maybe this is why they changed their formula?

Thanks for this *great* blog! Marina

Marina said...

Hi Susan! Thank you for the heads up on the difference between glyceryl stearate and glyceryl sterate citrate. There is one company in Australia that sells glyceryl stearate citrate (shop.newdirections.com.au). I cannot find it anywhere in the U.S. I think I will purchase it and combine it with the glyceryl stearate SE and see how it goes.

An update from 2 weeks ago: the lotion with glyceryl stearate SE has still not separated (after almost 4 weeks). Note: I wrote that I made it with glyceryl stearate, but it was actually glyceryl stearate SE.

Thanks for the list of ingredients for the Bach rescue cream. I think they completely changed the formula! The bottle I have at home (which I purchased 3 weeks ago) lists:

Ingredients: Beeswax, Caprylic/capric triglyceride, caprylyl glycol, cetearyl alcohol, cetyl palmitate, citric acid, glycerin, glyceryl stearate citrate, isopropyl palmitate, potassium sorbate, purified water, shea butter, xanthan gum.

Some issues: They listed ingredients in alphabetical order instead of in order of highest to lowest concentration. (What's up with that?) Also, they don't have any preservative except potassium sorbate. This seems a little sketchy to me. Maybe this is why they changed their formula?

Thanks for this *great* blog! Marina

Marina said...

Hi everyone: Just another update on Glyceryl Stearate SE. I mentioned that I made this lotion a little over 8 weeks ago:

73% water
0.5% Xanthan Gum
15% Fractionated Coconut Oil
5% Cocoa Butter
4% Glyceryl Stearate SE
3% Leucidal Liquid

Well, about 2 weeks ago it finally separated. It slowly started feeling more and more watery until it finally formed a visible water layer at the bottom. I guess this was a good lesson - thank you, Susan! You need to have a high HLB emulsifier with Glyceryl Stearate.

More useful information - six weeks ago, I did some experimentation with glyceryl stearate SE. I made some simple recipes to see what would happen. Note: I prepared these just to see what would happen, not to put them on my skin, so I did not add preservatives.

95% Distilled Water/5% Glyceryl Stearate SE: As of today this has not separated. It has a lotion-like consistency, but does not flow easily when I hold it upside down.

83% Distilled Water/4% Glyceryl Stearate SE/13% Cetyl Alcohol: As of today, this has not separated. It is even thicker than the one above. Will not flow; has no separation. Note: Cetyl alcohol has a required HLB of 15.5.

83% Distilled Water/4% Glyceryl Stearate SE/13% Sunflower Seed Oil: Looked great when I first made it, but after about 3 weeks, this started to separate. Note: Sunflower Seed Oil has a required HLB of 7.

83% Distilled Water/4% Glyceryl Stearate SE/13% Isopropyl Myristate: Looked great when I first made it, but after about 3 weeks, this started to separate. Note: Isopropyl Myristate has a required HLB of 11.5.

83% Distilled Water/4% Glyceryl Stearate SE/13% Caprylic/Capric Triglyceride: Looked great when I first made it, but after about 3 weeks, this started to separate. Note: Caprylic/Capric Triglyceride has a required HLB of ~5.

My take home lesson: There are a lot of people claiming that their only emulsifier is glyceryl stearate or glyceryl stearate SE. This is probably a lie. They may add a lot of cetyl alcohol to keep it thick and this may help a bit, but probably only temporarily.

Thanks for this great blog, Susan! Marina

bonton noodles said...

Susan. Where do you purchase your emulsifiers? Namely Ceteareth 20 and Glyceryl Stearate? I would love to find a Canadian Online shop but am not having any luck.

Bonnie

Susan Barclay-Nichols said...

Hi Bonnie. I buy these supplies out of Canada as I don't know any local suppliers. I shop a lot at Lotioncrafter as they are awesome. If you can get them shipped to the border, you'll save some money, but her shipping is pretty reasonable.

Magdalena Keating said...

Hi Susan,

I wanted to tell you how absolutely in love I am with your blog. I love how you integrate science into your blog. Its not just about following a recipe, it is about understanding what/why/how. I have even bought a chemistry for dummies (as I didnt do chemistry in my leaving cert in high school).

I am so grateful I have found something I am becoming deeply passionate about!

I am also passionate about the environment and really want to find ingredients that are as natural as possible but also products that do not contain palm oil derivatives.

At the moment I am really interested in making facial lotions/creams etc..

Currently the ingredients I bought and realised that have palm oil are: vegetable glycerin, cetyl alcohol, vegetable Emulsifying wax. After doing some digging, I have realised that all of these are palm origin, Supplier says palm and/or coconut and that their supplier doesn't have to disclose any further.

Are you aware what palm oil free and natural alternatives there are to the emulsifiers, humuctatnts as well as thickeners?

I've read that glyceryl stearate citrate and lecithin are palm oil free alternative as an emulsifiers - can these be used for making facial lotions? Can they be used interchangeably with a vegetable emulsifying wax?

I have also read that only carageenan, guar and xanthan gums are palm oil alternatives as thickeners and before I hunt these ingredients down, I wanted to ask you whether these can be used in place of cetyl alcohol and stearic acid?