At home, you probably store your ketchup bottles in the fridge. Yet, when you go to a diner, they have them sitting on the tables at room temperature. So, what's the deal? Should we be storing our ketchup in the pantry or in the fridge?
To get to the bottom of this food storage conundrum, we reached out to dietitians for their expert answers.
"Unopened, ketchup is good for about a year in the pantry. Once opened, expect ketchup to last about a month if it's not refrigerated," Isabel Maples, a nutritionist and registered dietitian with the Academy of Nutrition and Dietetics, tells Hunker. "How long it lasts, again, is a food quality, not a food safety issue, but it will last longer in a cool, dark place than it will if exposed to sunlight and heat."
Maples adds that ketchup ingredients like tomatoes, vinegar, salt, and sugar (which create high acidity) help keep the condiment safe at room temperature. However, quality will decrease faster, causing the color and scent of the product to change. By keeping it in the fridge, which is what the Heinz company recommends, ketchup is actually able to maintain its bright red shade.
Amy C. Keating, a registered dietitian, nutritionist, and the program leader at Consumer Reports, adds that the USDA FoodKeeper App confirms that ketchup should be refrigerated for quality control. "Shelf-stable commercial ketchup, cocktail sauce, and chili sauce are safe when stored at room temperature after opening," the USDA writes. "Quality, not safety, is the reason the labels on these products suggest that they be refrigerated after opening."
When it comes to why many restaurants still choose to keep ketchup on the table, Maples says that it's because they use up the ketchup faster than we do at home. Also, many establishments will refill the bottles on a daily basis.
So at the end of the day, you'll want to keep your ketchup in the fridge … unless you go through a bottle of ketchup a day.