Kraft Settles the Debate—Here’s Where to Keep Your Mayo

It didn’t seem like a heated issue, but when it came up in a team meeting, everyone had something to say. And after Heinz nearly broke the internet last month by settling the great ketchup storage debate, we realized the answer to mayo storage might not be as simple as we thought. So, we went straight to the source of some of America’s favorite mayo to get their expert opinion. Here’s what they had to say.

Where to Store Mayonnaise

Let's clear something up right away: While the usual advice is to store mayo in the pantry when it's unopened and in the fridge once opened, that's not your only option.

A 2016 report by the global information company NPD Group challenged the conventional wisdom, suggesting that mayo can be kept at room temperature even after opening. The report stated that commercially made mayo is acidic enough to "slow the growth of bacteria associated with foodborne illnesses." It also noted that commercially produced mayo typically uses pasteurized eggs instead of raw eggs, along with additives and stabilizers that help keep it shelf-stable when unopened.

Food safety experts at FoodSafety.Gov confirm this finding, saying, "Shelf-stable commercial mayonnaise is safe to store at room temperature after opening." However, this is only true as long as the mayo isn’t contaminated by dirty utensils or fingers—so avoid double-dipping when you're making that BLT!

So here’s the real question—can you store opened mayo in the pantry? Technically yes, but should you? Storing it in the fridge can extend its shelf life, potentially by up to 2 months, according to FoodSafety.Gov.

We reached out to Kraft Mayo for their take on this, and they confirmed the advice. The Kraft team sent us this message via Instagram: "Quality, not safety, is the reason our mayo shouldn’t be stored at room temperature. For the best taste, refrigerate it after opening and let it chiiiill!"

We asked our followers on Instagram, and a whopping 97% agreed: mayo belongs in the fridge. We think that pretty much settles the debate. Just like ketchup, your opened mayo should be kept refrigerated. And to the 3% of you who disagree—you're not technically wrong, and you won’t cause any harm, but let's just say you're outnumbered.