Here's something you maybe don't want to find in a package of food: a little mysterious package that says DO NOT EAT.
 
Soooo … if it’s not food, what’s it doing in the food?
 
Well, those packets contain desiccants, or materials that eliminate moisture, and you find them in all kind of products that would get ruined if they got wet -- this includes packaged foods, like dried meats; bottles of vitamins or other kinds of gelatin capsules; even leather products like purses and book bags.
 
Most of the time, the desiccants inside those packets are silica gel -- an artificial form of silicon dioxide, which is the same stuff that makes up sand and quartz.
 
And they deal with moisture in a pretty interesting way: through adsorption.
 
No; that’s not a typo. 
 
Absorption is when material permeates, or is drawn into, a substance -- like the way plant and animal cells, or the cells in a sponge, soak up water.
 
Adsorption, though, is when a material sticks to the surface of a substance. 
 
And those granules of silica gel are covered in tons of microscopic pores that attract and hold onto water molecules. And they do it so well that a single grain of the stuff can adsorb 40% of its weight in water. 
 
So, in the contained environment of your vitamin bottle or bag of pepperoni, water would rather be in the silica matrix than out in the food matrix, so that's where it goes, keeping the food nice and dry.
 
And if you're wondering why you shouldn't eat it...it's because it’s NOT FOOD! It’s like high-tech sand! Why would you want to eat that?
 
I mean if you tried, it wouldn’t kill you, but it would adsorb all of the moisture in your mouth, including your gums and tongue, causing so much discomfort that the Cinnamon Challenge would look like a great idea in comparison.
 
So, please, I implore you: Listen to the packet. DO NOT EAT! Just throw it away and enjoy your beef jerky or your leather purse or whatever.
 
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