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I have a high-fat cookie dough (see What ingredient changes will make this cookie dough more workable?) which wants to be chilled in the refrigerator overnight before shaping. I tried to cheat by chilling it for only 4 hours, which I figured would be more than enough time for the dough to get as cold as the fridge could make it.

I was wrong. When I pulled the dough from the fridge after only 4 hours, it was not nearly as stiff as it needed to be. The next morning, the dough was much stiffer and more workable.

What is it about an overnight (or longer) refrigeration that transforms the dough into something workable?

KatieK
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  • I don't suppose you tried 6, 8, and 10 hours? :) – jscs Dec 19 '12 at 03:18
  • Nope - no iterative testing, afraid. – KatieK Dec 19 '12 at 03:29
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    Did you divide in half, was the dough ball shaped or flat? The size and shape of the dough will effect the time it takes to chill the dough all through. I guess that one big ball might need all night, but one large flat/thin shape might be OK in 4h or maybe even 1-2h. – Stefan Dec 19 '12 at 06:30
  • I divided the dough in half, and smooshed the ball down to about 1 and a half inches. – KatieK Dec 19 '12 at 17:10

3 Answers3

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The rest period hydrates the starches in flour, giving the dough a firmer and more workable texture (there is some very minor gluten development, but its mostly the expansion of the starch bundles with water). In many cookies, the flavors will also mature and improve, especially with cocoa in the recipe.

In many recipes, the cooling from refrigeration is itself part of the point--doughs may be easier to roll and cut when they are cool due to chilling of the fat. Most dietary fats are waxy, which means they don't have a single set freezing/melting point, but rather get more viscous or eventually firmer then hard as temperature drops.

For example, linzer cookie dough is very frangible, and the chilling and hydration make rolling and cutting much easier.

Generally, most of this affect is going to happen in the first 8 hours or so. The overnight thing is simply for convenience in most cases. In fact, 4 hours is often enough, although obviously not in your case.

If the major effect is chilling in your recipe, by flattening the dough to a disk, or lengthening it to a log (thus increasing surface area) compared to a ball, it will chill more rapidly. You mentioned this is a high fat recipe--if that fat is butter (as it so often is with cookies), that may help.

SAJ14SAJ
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Generally - overnight chilling just ensures that you actually DO chill for 4 hours. However - in your case the fat needed to penetrate the flour and harden up. It's a slow process (deopending on the type of fat), but well worth the wait.

For example - olive oil hardens up in the fridge, but not in 4 hours, even though it reaches the right temperature. The structure has to change. Think about honey. It hardens up, but over a long period of time.

user12785
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    The mechanism in honey--crystallazation of sugars--is very different than the hardening of lipids, which is much more complicated. Waxy fats don't have a set freezing point. Really, their viscosity varies with temperature. If you ever made candles, warm wax is pliable but cold wax is seems quite hard, while hot wax is essentially liquid--but it is a continuous variability, not a phase change. – SAJ14SAJ Dec 19 '12 at 09:52
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I do not know the chemistry involved, but longer dough refrigeration toughens the dough, and makes it more cohesive. It, like any refrigeration, also changes the texture of the finished product (usually making it chewier).

daisy_ann
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