Cookie Question

October 27, 2008 8:25 AM

Why does putting a couple pieces of bread in a sealed container of cookies keep the cookies soft while the bread goes hard?

Nana brought us soft chocolate chip cookies and there was hard bread in the tupper ware. She explained that it kept the cookies soft. WHY.

Why do the cookies have a stronger hold on their moisture than the bread? Couldn't the bread suck out the cookies moisture? Why dont they suck out each others moisture equally? Who thought of this? How? If I put english muffins in there, what will happen?

posted by shadowfelldown to food & drink (14 comments total)

Why dont they suck out each others moisture equally?

It's the system reaching equlibrium. When you toss the bread in, it has much more moisture than the cookies. (If it helps, compare bread to toast to realize how much is really in bread). The system will stabilize somewhere around equal proportions of moisture in each. This happens to be just enough to keep cookies moist and tasty.
posted by chrisamiller at 8:33 AM on October 27, 2008 [1 favorite]

Yes, what chrisamiller said. My mom always did this with brown sugar so it wouldn't dry out.
posted by chococat at 8:34 AM on October 27, 2008

Lizzicide: you're going to get crucified for not googling.
Lizzicide: in fact i'm racing back to my desk to do it shortly
Lizzicide: damnit. beaten.
Shadowfelldown: nobody crucifying me!
Shadowfelldown: anyway, how can bread have more moisture? have you SEEN how much butter and crap goes into cookies?
Lizzicide: hahaha
Lizzicide: which are then baked
Shadowfelldown: so is bread!
Lizzicide: ... i don't know.

*I DID google this, but nobody came up with the WHY. Also, yahoo answers is useless.*
posted by shadowfelldown at 8:41 AM on October 27, 2008

Sugar is hygroscopic.
posted by sanko at 8:43 AM on October 27, 2008

Like sanko said, but with a bit more detail - sugar attracts water much more strongly than the gluten and starch and whatever else is in bread does. So the system is not actually reaching equilibrium, the cookies really are getting more moisture than the bread. Bread is just a convenient, readily-available, time-release source of moisture for the cookies.
posted by vytae at 8:47 AM on October 27, 2008 [3 favorites]

Like sanko said, but with a bit more detail - sugar attracts water much more strongly than the gluten and starch and whatever else is in bread does. So the system is not actually reaching equilibrium,

To be picky, the system is reaching equilibrium, it's just that that equilibrium is not equal amounts of water in each.
posted by DevilsAdvocate at 8:55 AM on October 27, 2008 [4 favorites]

Is anything more hygroscopic than sugar? What if you want to wick the moisture out of the cookies to make them crisp?
posted by crapmatic at 9:03 AM on October 27, 2008

crapmatic: Silica gel.
posted by zsazsa at 9:04 AM on October 27, 2008

crapmatic, there's more than moisture content to making a crisp cookie -- you can't remove the water from, say, a bit of flour and have a "good" sort of crispness. It'd just get hard.
posted by boo_radley at 9:32 AM on October 27, 2008

"Cookies" are in fact a hard concept to define. The only criteria that usually unites the species known as cookies is the fact that they are seldom built around a water-based dough. Bread is almost always water+flour (without sugar) while "cake" usually means eggs+flour+water+sugar.
posted by mattbucher at 9:51 AM on October 27, 2008

Staling of bread is complicated and not entirely dependent on moisture levels:

Staling is a chemical and physical process in bread that reduces its palatability. Stale bread is dry and leathery.

Staling is not, as is commonly believed, simply a drying out process. Bread will stale even in a moist environment, and stales most rapidly at temperatures just above freezing.(McGee 2004, p. 310)

Although the precise mechanism of staling is still unknown, one important mechanism appears to be migration of moisture from the starch granules into the interstitial spaces, degelatinizing the starch. This results in stale bread's leathery texture.
posted by jamjam at 9:57 AM on October 27, 2008

A comment from my mom: apple slices work even better than bread.
posted by rokusan at 9:58 AM on October 27, 2008

If I put english muffins in there, what will happen?

You could try it and find out ... :-) Sometimes the answers to life's questions can be found right around you, and you don't even need the web. It's what people did, before they had the web to answer their questions.
posted by exphysicist345 at 5:55 PM on October 27, 2008 [1 favorite]

See also products like Brown Sugar Bears. I find that we've been forgetting the soaking step which may be why it isn't working as well as it used to.
posted by dhartung at 2:20 AM on October 28, 2008