why do some eggs need to be refrigerated and some don’t?

Question

I’ve been curious after seeing non-refrigerated eggs in Japan

In: 2

Answer 1

Eggs in North America are more strongly washed before going to the store. This removes the natural outer protective layer that usually keeps them sealed and sterile. In Japan (and most of Europe too!) they leave this outer layer on the eggs and so they’re safe to store at room temperature because they’re sealed.