Ketchup

Ketchup contains a high concentration of vinegar and sugar. Vinegar gives it a tangy, acidic taste, while the sugar lends that hint of sweetness that helps balance the flavor of the tomatoes, herbs and spices. Both ingredients are potent preservatives that can help prevent the growth of microorganisms, giving ketchup a long life span and avoiding the need to store it in the refrigerator.

Ketchup generally lasts up to 1-2 years before opening, after which you should use the product within about a month if kept in the pantry. Keeping ketchup in the fridge may help ensure it lasts longer and the flavor suffers less deterioration over time, but it's unnecessary if you don't have enough free space in your fridge. Because products can vary, read the back of the ketchup bottle for more specific storage instructions.

Ketchup generally doesn't contain wheat or gluten, but this doesn't necessarily mean it's gluten-free. In some cases, ingredients added to the ketchup may have been processed with wheat or rye derivatives, or the manufacturer may mix and bottle the ketchup in a facility that also processes other sauces and condiments containing gluten.

Many popular ketchup brands, such as Heinz, are gluten-free. If the bottle you're looking at doesn't specifically include the term "gluten-free" somewhere on the packaging, it may be

Like other condiments, ketchup eventually expires. Typically, you won't notice mold growth or other telltale signs of this because of ketchup's acidity, but the product may taste blander or start to develop off flavors and smells. These changes shouldn't happen if you store the product correctly and use it by the expiration date printed on the packaging.

Before opening a bottle of ketchup, store it in a cool, dry place, such as inside a pantry. If you can't finish the entire bottle within a month after opening it, consider keeping it in the fridge to maintain its flavor profile and freshness.