First off, that little date on the jar isn’t a hard stop sign. For mayonnaise, it’s more like a gentle suggestion from the manufacturer about peak quality.
Think of it like a traffic light. The expiration date is the yellow light—slow down, pay attention, but you don’t have to slam on the brakes. The real question is: what’s happening inside that jar?
Why Mayonnaise Is Surprisingly Tough
Mayonnaise has a secret superpower: acid. The vinegar and lemon juice in the recipe create an environment where most nasty bacteria just don’t want to live. It’s like a tiny, sour fortress.
Plus, commercial mayo is usually pasteurized. That means the eggs inside have been heat-treated to kill the scary stuff before they even hit the jar. So, your expired mayo isn’t a ticking time bomb—it’s more like a sleepy, forgotten island.
But here’s the catch: this only works if the jar hasn’t been contaminated. If you dipped a dirty knife in there or left it out on the counter for hours, you’ve broken the fortress walls.
