Friday, February 4, 2011

Thickeners: Xanthan gum

I've written about xanthan gum before, but I thought I'd go a little more in depth in this post!

Xanthan gum is an anionic polymer derived from the bacterium Xanthomonas campestris, which can be found on cruciferous veggies like cabbage, cauliflower, and broccoli (all of my least favourites!). In the manufacturing of this ingredient, they actually use the bacteria in a fermentation process. It's permitted in food and cosmetic products and the typical usage is about 0.1% to 0.3%.

It dissolves in most acidic solutions (less than pH 7) and shows great stability in presence of most organic acids (like vinegar, lactic acid, AHA, and so on). It also shows good compatibility with many basic compounds, but something that is very alkaline like lye (pH around 12), you might see some precipitation of xanthan gum and salts. It is also unusually good with salts, but solubility is an issue. There is an incompatibility of xanthan gum and metal ions in solution with high pH, so addition of EDTA is a good idea if you're using some high pH ingredients like lye (although I can't see a good reason to make a really high pH product...)

Xanthan gum shows good compatibility with non-ionic surfactants in high concentrations - which means surfactants like decyl glucoside that don't contain a ton of salts with thicken nicely with it - but low concentrations of anionic and amphoteric surfactants (just about every other surfactant). It's not compatible with quaternary compounds, or you want to avoid using something like BTMS, honeyquat or polyquat 7, or Tinosan as your preservative. Salts can slow down the hydration of xanthan gum, but don't have much of an effect on it once it's hydrated, so don't worry about adding things like aloe vera that contain a ton of electrolytes.

You can use xanthan gum in your lotions in the oil phase of the lotions (which doesn't make sense to me as it is a water soluble ingredient, but that's what the data sheet suggests) and in your surfactant mixes in the heated water and surfactant phase to create a rich creamy lather. But remember, if you're making a shampoo, leave the honeyquat and polyquat 7 out!

Make sure you're using 0.1% to 0.3% because at lower levels in a lotion, it can actually enhance flocculation and creaming (otherwise known as an epic lotion fail)! So don't go below 0.1%. I've been experimenting with xanthan gum and Sucragel in lotions, and I've found 1.5% to 2% thickens a Sucragel lotion very nicely (and they're usually quite thin, no matter how much cetyl alcohol or butters you include in the mix).

Xanthan gum is pseudoplastic, so when it is subjected to stress it will thin out but will thicken up again when the stress is removed. And although it won't dissolve in alcohol, it is compatible with up to 60% alcohol, so it is an ideal thickener for making hand sanitizers. And like the other gelling agents we've seen so far, it will help decrease the freezing point of your products so they're easier to ship or store.

As a note, xanthan gum works really well in concert with other gums or thickeners. It works best with guar gum (80% guar gum to 20% xanthan gum) and with locust bean gum (50-50).

Join me tomorrow as I start experimenting in the workshop with these various thickeners in various products!


Anonymous said...

Swift, can you let us know which supplier your xanthan came from? THanks!

daniel said...

You can get xantham at many supermarkets, brand is called bobs mill.

Swift, I asked you about this before, but would you cover fatty alcohols? They are thickeners, but NOT like fatty acids, or esters. COOH vs OH functional group.

I ask because you may very well find out things I haven't. Thanks.

Susan Barclay-Nichols said...

Hi Daniel. I've written two posts on fatty alcohols - cetyl alcohol and cetearyl alcohol. If you could give me more information on what you are seeking or share what you know, we can always add to the posts. The more information, the better!

Nancy Liedel said...

I hate, loathe and detest Xanthan Gum. It's not personal...well, it is. After one of our boys was diagnosed with autism, everyone and their uncle told use to put him on a gluten free-casien free diet. I did, using xanthan gum to thicken things. It's was a miserable two months. No change in son and we just chucked this disaster. I'm going to be open minded and fair about this. I may even give it a try, but I'm not convinced, yet. More for you!! :)

daniel said...

Absolutely. Well, I know that they are good surfactants since they have an OH part. The big "AHA!" was when I learned they are more water soluble than fatty acids due to the fact fatty acids have an extra O atom. This makes fatty acids "self stick", so they are less accessible to the water phase. That is in addition to their carbon tail clumping them in the oil phase.

In contrast, only the carbon tails of fatty alcohols clump, leaving their oh heads available to the water phase, thus providing increased water solubility. Prob why cetearyl is in pola/ ewax.

With that, I invite you to experiment and share your results :)

Currently, I'm contrasting the high weight/ long tail of behenyl to lower of cetyl. Measuring the differences in thickeness, stability of emulsions...

To the labs!

Anonymous said...

Hi Susan! Just wanted to make sure I understood right, is it ok to use xanthan gum up to 2%, even for mild facial cleansers? Some say xanthan gum lowers the shelf life of products. Is that true? Lastly, I really like using polyquat 7 because it makes using the soap a lot more pleasurable, what would be a good substitute for this if I cannot use pq7? Thanks!

Anonymous said...

I have a lotion recipe that I made but the lotion is a little thin. Is there a way I can thicken the already-made lotion using xanthan gum?

Susan Barclay-Nichols said...

Check out the answers to your questions in this post on xanthan gum! Thanks for the inspiration for today's post!

Anonymous said...

Hi Susan,

really very interesting and helpful tips in your site.
I have a great problem with using Xanthan gum, please can you advise me :
I am using 30% SLES and 1% Xanthan along with 2% Lauryl Alcohol.
The Xanthan separates on standing. Please can you advise what can I do to avoid the separation in the mentioned formula.
Thanks a lot for your help and early reply.

Susan Barclay-Nichols said...

Hi John. Thank you for your kind words about the blog. I offer what I can.

My suggestion would be not to use it as xanthan gum is a very limiting ingredient and can be such a pain in the bum, so switch to something easier to use, but I don't think that is very helpful. :-)

I'm not a fan of xanthan gum, to be honest. I find it feels sticky and can make things pill on my skin. Some people like it, and perhaps someone can make some suggestions for you.

Jezzy Yama said...

I love your blog. There's so much info in them. On the topic of xanthan gum, I used xanthan gum mixed with distilled water and use it as a mask for clearing my pores. I mixed it into a paste and then spread on my face. I cut a piece of tissue and split them into 2 pieces. Spread the xanthan gum with a brush on my nose and cheeks. Let dry then put another coat. After this coat I paste one piece of tissue on the nose and slowly press down without breaking it then I coat another layer of XG over the tissue then paste the 2nd layer of tissue on top and end with another coat of XG. I let the whole thing dry and peel it off like a pore strip. It actually takes out those black and white heads.

Some people use XG in face serum but I read there is another product called sclerotium which is just as good as a thickener.


Alex said...

Even though xanthan gum is water soluble, it's added in the oil phase to prevent clumping since it tends to clump up when added to water directly.

If you're working with an oil free formula, it's a good idea to mix the xanthan gum with a little bit of pure glycerin first.

Anonymous said...

Can you please explain to someone with limited chemistry knowledge what the net effect of combining a nonionic ingredient like Xanthan gum and a cationic ingredient like Honeyquat would be? Would the formulation fall out of suspension? Would one cancel out the properties of the other? Thanks!

Anonymous said...

hi susan.....
can u suggest the ratio of xanthan gum with Hydroxypropylmethyl cellulose for face wash gel formulation...

Bilalahmad Shafiq said...

hi susan i appreciate you are doing really a great work.
can you kindly tell me we use xanthum solution in oil phase or use directly in oil phase???

Kavya said...

Hi Susan

I am thinking of using xanthan gum in hair gel but I heard that it makes hair dry. Could you please let me know if it is true as I already have very dry hair?

Anonymous said...

Hi Susan,

Did you experiment with xanthum gum in the oil phase yet?

Susan Barclay-Nichols said...

Hi Anonymous. Yes, in quite a few things! And it worked well!

ram, chennai said...

hi susan, i am trying o make a detergent powder using less concentrations of xanthan gum...should i use a preservative ?

Susan Barclay-Nichols said...

Hi Ran! I'm sorry, but without having information about your recipe, I have no idea. Why are you using xanthan gum in a powder?

Ester said...

Hi to all!

I like xantan gum a lot, edible and easy to find. only problem with xantan gum is how to dissolve it quickly and without making clumps . Can anyone reccomend solution ?

Varun said...

need help.. We are developing a mild toxin free surfactant for babies using the below ingredients

- Decyl Glucoside (plantacare 2000)- 10%
- Lauryl Glucoside (Plantacare 1200) - 5%
- Disodium cocoamphoacetate 5%
- Cocamidopropyl hydroxysultaine 5%
- Sodium Cocoyl Isothionate 9Jordaporn CI Pril) 3%
- Disdoium EDTA
- Xanthan Gum
- Glycerin
- Depanthanol
- Calendula Extract
- Sodium Benzoate
- Potasium Sorbate
- Citric acid

Our process for sampling is is

Creating a gel with 1% Xanthan, 2% Glycerin in hot water with strong stirring for 10 minutes first

Then adding all the other surfactants followed by other ingredients to the gel with slow stirring for about 15 minutes.

Now about the issue.

We have tried multiple combinations but we are not able to remove lumpiness of Xanthan gum which is impacting the texture and homogeneity of shampoo , the viscosity is also a slight issue