Hillside Hot Cocoa Why Is There A Warning Against Pouring Out Hillside (Self-Heating) Hot Cocoa?

Why is there a warning against pouring out Hillside (Self-Heating) Hot Cocoa? - hillside hot cocoa

Well, I was idling around my local Wal-Mart, and I found a rare commodity: cocoa warmed. It uses a two-chamber, which is broken by a seal that is water with lime and heated the drink in about 10 minutes mix. Tasting is pretty wild, wicked. Anyway, I read the warnings, and one of them, I could not explain the life of me, "Do not pour the drinks packaging. I have no explanation for it." Cocoa is chemically unstable, without the box? Why the devil, that is to be activated? I hope that one of the brightest minds for an explanation.