4

I have used xanthan a few times, sometimes successfully, sometimes less so. The one thing I've noticed: it is certainly not enough to just stir it in until it is well dispersed. Sometimes it will not thicken no matter what I do, sometimes it will stay liquid for ages while I'm stirring and then suddenly become one big gloop with no taste left. And sometimes it will get thicker with whisking and then get back to liquid.

Following factors could play a role:

  • stirring
  • whisking (actively beating air into it)
  • time (maybe I have to leave it to hydrate on its own?)
  • temperature: I have gotten it to thicken at room temperature, but does it work better or worse when hot or cold?
  • liquid ingredients: How does the percentage of sugar, fat and other solids influence it? What about pH?

Can somebody explain

  1. How do the above factors affect thickening, and
  2. What is the most efficient method to get a liquid thickened?
3

The viscosity of a xanthan solution is virtually unaffected by temperatures from freezing point to boiling point of pure water and it hydrates rapidly in cold water. You don't need to let it sit on its own and the temperature doesn't matter.

The viscosity of a xanthan solution lowers when whisking or stirring, a process known as shear thinning. When you stop whisking, it will return to its previous viscosity. This will not factor in to thickening. That being said, you can get a xanthan gum foam using an immersion blender.

Between pH 1 and 13, the viscosity of a xanthan solution is practically constant. Unless you're using it for a strange application, you're good.

I cannot find any information on sugar or fat or other solids and their interaction with xanthan gum. Anything that can be dissolved in water would theoretically affect the xanthan gum's effectiveness, so I would expect sugar to be an issue, but fat or solids are obviously not.

The only thing you don't address is the concentration of your xanthan gum solution. Modernist Cooking Made Easy suggests a by weight ratio of:

  • 0.2% ratio for light thickening
  • 0.7% for a thicker sauce
  • and up to 1.5% for a very thick sauce

Additionally, the thickening effects only hold up for a day or two. What are you trying to thicken, specifically?

References

2

Are you measuring your xanthan gum accurately, with a scale that goes down at least to tenths of a gram? The practical range of application is about 0.05% to 0.8% of the weight of the liquid. Much above that and it will be very snotty and unpleasant. You've got to measure it quite precisely if you want reproducible results. If you need a scale for modernist ingredients, an inexpensive model like this works quite well http://www.amazon.com/gp/product/B0012LOQUQ .

2

Besides the points made by derivative and Michael, I noticed that it helps to mix the xanthan gum first with some other dry powder and to hydrate it by mixing it at very high speeds. When I use it in a salad dressing I mix well some sugar (5 times by weight) with the xanthan before pouring it into the food processor. The sugar separates the xanthan grains around. One then has to blend the mixture for a minute before the salad dressing thickens. The salt is added last, as it interferes with the hydration, but is fine to add once the liquid has thickened.

For using it with flours, I mix it first with corn starch. Other dispersion techniques I read about, but have not used, are mixing it first with a non-solvent, such as oil or alcohol, in a blender for several minutes (that is what it said) and then using the resulting slurry.

The Handbook of hydrocolloids has a long chapter on xanthan gum and its food applications, and Martin Lersch updated in February 2014 his Texture, a hydrocolloid recipe collection, which has many tested recipes.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.