Does Ketchup Need to Be Refrigerated? Here’s the Sticky Truth

Between all those burgers and hot dogs, we’ve been squirting ketchup on just about everything this summer. But where we store the bottle post-drizzle is another story. Does ketchup need to be refrigerated? Or can it be kept in the pantry for good? Here’s the sticky truth. 

It’s a debate as old as, well, ketchup. Those who keep their ketchup at room temp have likely never gotten sick from doing so and argue that restaurants leave communal ketchup bottles out on tables for hours. Those who keep theirs cold may refer to the instructions on the bottle itself, or even Heinz’s FAQ section, which reads: “Because of its natural acidity, Heinz Ketchup is shelf-stable. However, its stability after opening can be affected by storage conditions. We recommend that this product be refrigerated after opening.”

So, what gives? It really all comes down to your ketchup’s quality and personal preference, but at the end of the day, refrigerating ketchup (and pretty much anything) will extend its shelf-life. Ketchup will last for a year in the pantry if unopened, but once it’s been opened and unavoidably exposed to air, its quality will start deteriorating if it isn’t refrigerated. If chilled, however, an opened bottle of ketchup can last for up to six months, according to the Institute of Agriculture and Natural Resources at the University of Nebraska-Lincoln. But its quality may begin to deteriorate within the first four weeks of being opened. Oh, and if you’re still wondering about restaurant ketchup, they go through those table bottles way faster than one family or person would. But they’re also filling those bottles for single-day use from a massive bulk container of ketchup that’s kept—gasp—in the refrigerator. 

In terms of safety, there’s no real need to refrigerate ketchup. Tomatoes and vinegar, the main components in ketchup, help preserve the condiment at room temperature due to their natural acidity. Warm ketchup won’t make you sick and won’t necessarily spoil, but you may notice changes in color (thanks, oxidation), smell and taste once it’s been opened and hanging in the pantry for a month or so.

So, if you prefer your ketchup warm, go ahead and leave it on the pantry shelf. Just be sure to use it up before it gets a color or scent you’ll find unappetizing. But if you want your ketchup to look and taste just like the first time you used it, pop the bottle in the fridge to maintain its quality.

It’s also important to note that these rules apply to store-bought, grade-A ketchup. Homemade or low-quality ketchup may not have the preservatives (natural or otherwise) to hold its own in a room-temperature pantry. If you made your own, play it safe by storing it in the fridge. 

P.S., ketchup is also a surprisingly great (and tangy) substitute for tomato paste. As long as your recipe doesn’t rely on tomato paste exclusively for thickening, ketchup will fill in for it just fine. You can also reduce ketchup in a saucepan on the stove to get a more similar consistency to tomato paste before substituting. Hey, the more you know.