[chrislehrer]

I made a jus gras according to the recipe in Modernist Cuisine at Home. This calls for initial thickening of stock by adding xanthan gum to the liquid while processing with an immersion blender.

In terms of taste and texture, it worked well. But I was surprised: as soon as the gum hit the whizzing stock, the mixture turned ivory-white. (The stock was medium brown to begin with.)

Is this normal with xanthan gum? I'm using Bob's Red Mill brand, if that matters.

Is there a way to produce the same clean GF thickening effect while retaining a more natural-looking brown color?

 

[mike9]

Having never used xanthan this is interesting to learn. I'm leaning toward agar agar for clarity of end product.

I want to experiment with hard cider glazes thickened with agar agar.

 

[chrislehrer]

I'm testing agar right now, actually. I'll let you know how it goes.

There are problems with agar:

1. It has to be heated to boiling and simmered 3-5 minutes to hydrate fully. This changes the flavors of many foods.

2. You have to do your thickening by mass: you can't add some and see how it goes.

Note that most thickeners change properties somewhat in the presence of both alcohol and acid, both highly present in hard cider. You'll need to do some research there!

 

[cheflayne]

I have never experienced anything similar with xanthan gum. Did it actually turn ivory white or just lighter in color? What was the recipe?

 

[chrislehrer]

I have never experienced anything similar with xanthan gum. Did it actually turn ivory white or just lighter in color? What was the recipe?

Recipe: to 200g cold stock I added .8g (0.4%) xanthan gum powder and puréed with an immersion blender. I'm going to do it again as a test and will post a photo, but it turned ivory white immediately.

 

[chrislehrer]

Hmm. Okay, this turns out to be more complicated than I'd imagined. Here's a step-by-step:

200g cold brown turkey stock, semi-gelatinous when cold.

.8g Bob's Red Mill xanthan gum.

Pureed together with an immersion blender until thick and smooth. As you see, it turns ivory-white. This happens almost instantly.

I then warmed the mixture to a simmer, stirring, to see what would happen. I began to notice traces of brown within the white. I strained it fine and kept stirring gently, then skimmed off some scum. The result:

So it appears that the white coloring is basically foam. But while that's interesting, it's no help if I can't get the xanthan gum to disperse without it turning white like this. I've read that it makes no difference what the temperature of the fluid is, but maybe I should have had the stock simmering or something? I note, too, that the final result is not as clear and nice-looking as the original, though it is not white any longer.

 

[chrislehrer]

Further: while working on this post, it cooled, and most of the remaining fog precipitated on the surface as white powder -- which suggests that some of the xanthan gum never hydrated in the first place. This makes me wonder.

1. Does xanthan gum need to be pureed into the fluid for a long, long time until it begins to clear all by itself?
2. Is my batch of xanthan gum problematic in some way?

Can anyone tell me what should happen when I add xanthan gum to cold liquid with an immersion blender?

 

[drirene]

I googled using xanathan gum in making gravy (otherwise I know nothing about the topic). Nowhere could I find it turning white. This youtube is a pro making brown gravy with xanathan gum and it stays brown. Hope this helps a little.

 

[chrislehrer]

@drirene --Thanks! Interesting. He starts with a hottish liquid, I notice. I'll try and see if that changes anything. Otherwise I'm stumped!

 

[chrislehrer]

Okay, now this is really weird.

I heated some of the same stock to a strong simmer. Off heat, I put in the immersion blender and started it running, with the xanthan gum ready to add.

BEFORE the gum was added, the stock foamed white, with a dark brown base underneath. With the motor running, I added the gum and got the same ivory sauce as before.

Is there something weird in my water? I've never heard of this! I've even had a good well test in the last year, and while the water came up marginally hard, there was nothing surprising or worrying about its contents.

 

[someday]

My guess is you are blending in air which is refracting the light and making it appear cloudy. The additional viscosity of the liquid now traps the air bubbles--heating the liquid probably helped to mitigate this since the trapped air was able to "escape" once heated.

Your stock doesn't look particularly fatty, but blending fat from the stock while capturing it with the xanthan could also be having an effect.

 

[chrislehrer]

How much do I need to beat the liquid to disperse the gum? I'm wondering if I could solve the problem with a wooden spoon and elbow grease.