Friday, May 23, 2014

Question: Can I add glycerin to a lotion bar?

In this post on lotion bars, anonymous asks: How can you get glycerin to mix in a lotion bar? Do I heat to a certain temperature? Mix the wax and glycerin first before I put in my heated oils? Help I love glycerin in all my products.

If you are wondering if you can mix two things, may I suggest a visit to the newbie section to learn more about what exactly our products are about in two posts I call what you need to know about making any product (part one) or (part two)? I've worked hard to create a section with all the basics you might want to know about our products, and I think it might be helpful for this question.

Lotion bars are what we call anhydrous products. Anhydrous means "without water". "An" means without and "hydrous" means water. Anhydrous products are those that contain only oil soluble ingredients and no water or water soluble ingredients.

What are water soluble ingredients? They are ingredients that contain water or mix well with water to form solutions. They are things that will dissolve or mix in water to create a uniform looking product. These would include things like water, alcohol, hydrosols, water soluble extracts (hydrolyzed proteins, vitamins, minerals, plant based things), powdered water soluble extracts (like green tea extract), and humectants (glycerin, sodium lactate, honey), to name a few.

From the post on lotion bars:
What happens if you mix a water based thing into an oil based thing? You will get separation. Oil and water don't like each other (check your salad dressing to see this in action). If you add a water based thing - glycerin - to an oil based thing - shea butter - it will eventually seep out as the water and oil repel each other (this isn't exactly true, but it's easier to explain it this way...) If you really want to include glycerin into your product, you'll need an emulsifier.

Related posts:
Emulsification: What's that then?
Emulsification: A more in depth

The quick answer is that you can't add glycerin to an oil soluble lotion bar without an emulsifier.

Related posts on making lotion bars:
Newbie Tuesday: Let's make lotion bars! 

Back to basics: The basic recipe
Back to basics: Lotion bars - tweaking the waxes
Back to basics: Lotion bars - tweaking the butters and oils
Back to basics: Lotion bars - let's get complicated
Back to basics: Lotion bars - wrap up and link-o-rama
The chemistry of our nails: Lotion bar with lecithin and lanolin


Anonymous said...

Hi Susan,
How could Lush be using glycerin in their lip balms? Assuming that the rule (as I understand it) is that ingredients are listed in order of amount (highest first), then it seems that they're not skimping on the glycerin here. Would they just be hoping that a physical emulsification would hold up long enough for the product to be used before separation occurs?


Anonymous said...

I meant to post the ingredients here too.

Fair Trade Shea Butter (Butyrospermum parkii) , Apricot Kernel Oil (Prunus armeniaca) , Glycerine , Beeswax (Cera alba) , Cocoa Butter (Theobroma cacao) , Organic Extra Virgin Olive Oil (Olea europaea) , Tangerine Oil (Citrus reticulata) , Flavor , *Limonene , *Linalool


Susan Barclay-Nichols said...

Hi Erin. Can I share my honest opinion? I don't know how Lush does what they say they do and I think it's because they seem to leave things off the ingredient list of their products or hide ingredients within the name of other ingredients - like using "parfum" to hide their preservatives. So I have no idea how they do what they say they do. There's nothing in that ingredient list that would allow them to incorporate glycerin into the product. There are no emulsifiers in the product, so no water soluble things can be incorporated.

Anonymous said...

Just as I thought too ;)
I've looked at a lot of their product ingredients and am becoming more and more leery of the company because of what I see and how it's presented. I'm not one to favour any company that dupes their customers.
I am by no means qualified to make strong accusations about their ingredients but have seen things that are most likely acting as preservatives listed as 'fragrance' too. The average consumer is going to happily assume that these are preservative free products.


Dian Tardiff said...

Hi Susan! Thank you so much for all your wonderful information. Recently my neighbor brought over a lotion bar she uses when knitting. She absolutely loves it and wondered if I could make one. When I reviewed the ingredients, all it had was Shea Butter, Cocoa Butter and Glycerin Wax. The Glycerin Wax threw me a bit. I know from your lovely posts that glycerin does not mix with oils. But how could a wax be made of glycerin? Where would I find it? Do you know anything about it?

Thank you so much.

Susan Barclay-Nichols said...

Hi Dian. I have no idea what glycerin wax might be. I did a google search and no such thing exists. I'm wondering if it should "glycerin, wax" and the punctuation is missing?