Sunday, September 26, 2010

Better crafting through chemistry: Sorbitol


In this post on humectants, Aesthete asks: I was re-reading this post on humectants and was wondering if you've ever formulated with sorbital? It's described as having "excellent plasticizing & thickening effects providing viscosity & texture, stabilizes gels & provides good clarity, effective moisturizing properties, good smoothing & conditioning effects." It almost sounds too good to be true...I really value your opinion and if you have one on this ingredient, I would love to hear it. Thank you.

Sorry, Aesthete, but I've never formulated with sorbitol, but I can share my book learnin'!

Sorbitol is a water soluble humectant originally derived from berries and fruit that can be used at 0.5% to 15% in our creations. We generally find it in a 70% aqueous solution that is easily dissolved in water but not so much in alcohol. It's a sweetener that can be used in toothpastes and mouthwashes as well as diabetic foods, but it has a laxative effect if you ingest too much (more than 20 grams per day!).

Like other humectants, it's a thickener and a desiccant, meaning it absorbs water away from other ingredients (like those little DO NOT EAT packages we find in computer parts or shoes). It will help thicken your lotions and surfactant based products, increase clarity in bubble baths and body washes, and reduce the freezing point of our products.

You can combine it with glycerin to reduce the feeling of tackiness from that humectant, although it has a little tackiness of its own.

On the scale of hygroscopic abilities, it rates below our other commonly used humectants (the scale looks like this - sodium PCA > sodium lactate > glycerin > sorbitol).

So does it do all those wonderful things you mention? Yep. It's a moisturizing and conditioning ingredient - it draws water to our skin to increase moisturization and make it feel nicer. The smoothing part means it will make your skin feel smoother, and it will do that. It is a plasticizer in that it increases the fluidity of our products. It helps increase clarity of our surfactant based products and decreases the freezing point.

But these features aren't unique to sorbitol - glycerin and propylene glycol will do these things as well. In fact, glycerin is highly recommended for dry or wrinkled skin because of the moisturization and conditioning properties. So why use it?

It's a good substitute for glycerin as it is less tacky than that humectant, and it's a good substitute for propylene glycol for those who don't wish to use it. It won't make you sun sensitive like sodium PCA or sodium lactate. You can use it as a humectant in deodorants at up to 5%, but don't use it as the main polyol in that product as it won't work well.

Hope this answers your question!

15 comments:

mariefel said...

im just wondering i saw one person making a lotion in a lab...it seems like its like the base was transparent type....when i ask he just said that i was because of "carbopol"...what is that thing???can you give a hint of this carbol...tnxxx

Susan Barclay-Nichols said...

Hi Mariefel! Check out this post on the topic or this one or this one or this one. I do like carbomer for formulating fun!

mariefel said...

hello susan thank you for reply...the links that you've gave me are all in cold process right...?
if ever i will use carbopol in making lotion with heat process method...water, oil, emulsifier....where should i put the carbopol...thank you

Anonymous said...

to add to Susan's answer : when used as a humectant, liquid sorbitol can replace most other humectants, weight by weight, while providing effective hydrating properties, where the humectant % is < (less than) 10 % of the formulation; in emulsions, it can be more effective than glycerin. again, upto 10 % of formulation. another factor that makes liquid sorbitol a good addition is that its rate of water loss or gain, in dry or humid atmosphere, is very slow. overall, a good ingredient to use in formulating cosmetics.
very impressive blog Susan ! thank you, good luck and best regards.

Marjo said...

Hi susan! I am suddenly obsessed with this plasticizer reference... Sorbitol is one of them
I think cyclomethicone is increasing spreadability so that is a plasticizer too? Or do they also need to do filmforming?
Are there more like these
and would we want them to be
in a formulation?

Susan Barclay-Nichols said...

Hi Marjo! I'm answering your question in Sunday, January 4th's Weekend Wonderings. Great question!

Danny A said...

Susan , I love your blog... and my hats off to you.

Thank you for sharing this highly valued informative science for all to understand.

Rosa Megasari said...

Hello. Very nice post. I have some question. I'm currently making some soap (lye+oil) and add sugar water to increase bubble and clarity. Can sorbitol subtitute the sugar water? Thank you.

Susan Barclay-Nichols said...

Sorry, Rosa. I don't make soap so I can't make a suggestion for you. But I wonder if you'd want to buy an ingredient that's hard to find like sorbitol over making your own sugar water?

Jim said...

Rosa, I am a CP soap maker, and Sorbitol is better than sugar for increasing lather. Sugar tends to brown and causes the soap mixture to really heat up. Sorbitol does not do this.

Kate Gordon said...

Can we make our own sorbitol at home from berries or other glucose source? Please respond to my email I am trying to inexpensively obtain enough formula ingredients to make a boatload of home made fake skin for our boy scout troops! Sorbitol is 15 dollars for 20 oz!!! At our pharmacy...so could use some help finding it in larger quant like a 5 Gallon drum or something lol. We will use it along with glycerine another costly ingredient and regular Knox jeletin and of course some red yellow blue green. Flocking material...
ANY HELP finding these items in quant will be remembered and appreciated. thank-you... Kthrngordon@gmail.com. or 1(406)899-4863. Ask for Kate.

Kate Gordon said...

Still wanting to find a recipie for home made Sorbital. Can any one help me out with this? Thank you.;-)

Susan Barclay-Nichols said...

Hi Kate. I don't understand how one could make sorbitol at home. That's really like asking how to make soy bean oil at home. It's an industrial process to make it, and you should be able to find it at various suppliers in your country. I have a list of suppliers for various countries in the FAQ of the blog, and I encourage you to check it out so you can find somewhere that might be cheaper.

Glycerin is dirt cheap. I get it at $7 a litre, so whoever is asking more than that is really ripping you off. You really need to find a proper cosmetic supplier from whom you can order things.

If you're in North America, I will suggest checking out Lotioncrafter.com or Makingcosmetics.com as sorbitol might be found there. As for glycerin, everyone carries it, so check out the FAQ for a supplier near you.

D D'Angelo said...

I was searching the blog looking for a way to keep my spray conditioner from freezing in the mail and am thinking that this could be the answer. What percentage would I need to use? I use your leave in recipe, basically. Thanks! Dean

ashwin meshram said...

Hi SUSAN,
i used sorbitol instead of glycerin. how it will effect on my product.i used same quantity as per glycerine ?/