system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How can you store baked goods at room temperature for days when they contain things like butter and dairy?

I just made a batch of muffins, and the recipe says "store at room temperature for up to five days." But the recipe includes butter, dairy, eggs... things that would normally be prone to spoilage if left out. How is this ok? I just want to make sure because I'll be serving them to a group of people and I don't want to make anyone sick! 

Edit: Thank you all so much for your explanations-- I really learned a lot. :)
gpt
Butter and eggs can actually be left out on the counter for days without spoiling. Refrigeration of those items is more of an American convention than a requirement. 


Milk does spoil at room temp, but it's lifespan is increased through pasteurization. If you've ever bought raw milk, you'll notice it starts to smell funky after a couple of hours being left out on the counter, whereas regular pasteurized milk can survive a few hours on the counter and way longer in the fridge than raw milk does.

By this logic, when you bake your cookies or cake in oven at 350 degrees, you're definitely going to kill any and all bacteria in the milk that cause the milk to go bad (and evaporating lots of moisture out of it as well) leaving behind only the necessary fats and proteins for holding your dessert together.

Edit: turned desert into dessert, yum.