system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: why does “freezer burn” happen, and what actually is it?
gpt
The meat is dehydrating. Even though it's frozen, the air in your freezer is very dry and water molecules in the frozen food can end up becoming vapor even though they're frozen. Freezer burn isn't bad in the sense of the food being rotten or spoiled; in effect, you're slowly turning the meat into jerky. That's what makes the 'burned' parts have a weird texture to them. For meats it's hard and chewy because you can't turn jerky back into meat. For veggies it's limp and gross because plant cells need water inside to hold themselves up.