An open box of baking soda has long been the go-to fridge deodorizer. Another version is making the rounds: a small jar of used coffee grounds, left uncovered on a shelf. Here’s what it actually does, how to prepare the grounds so they don’t turn moldy, and the one thing it can’t fix.
In short
- Dry your used coffee grounds, put 2 to 4 tablespoons in an open jar and set it on a fridge shelf.
- The USDA lists coffee grounds, like baking soda, among the ways to deodorize a fridge.
- The grounds must be completely dry, or they can turn moldy.
- They don’t remove the cause of a smell: spoiled food has to go first.
What the jar is for
The tip, shared by El Cronista, is simple: “Coffee helps reduce or mask odors.” The site explains that the porous structure of the grounds can hold on to some of the compounds floating in the air, while their aroma makes other smells less noticeable.
It isn’t just an internet trick. The USDA’s own advice, quoted by Apartment Therapy, is to “sprinkle fresh coffee grounds or baking soda loosely in a large, shallow container” in the bottom of the refrigerator and freezer. The Apartment Therapy writer tested it with used grounds and says, “Coffee contains nitrogen, which helps neutralize odors rather than simply covering them up.”
How to do it
- Drain the grounds well after brewing.
- Spread them on a plate or a tray and let them dry completely. Apartment Therapy warns that “damp grounds can get moldy pretty quickly.”
- Fill a clean jar with 2 to 4 tablespoons and set it on a stable shelf, El Cronista advises.
- Leave it open. “It is important that the coffee is not covered, since it needs contact with the indoor air to do its job.”
- Replace the grounds as soon as they turn damp.
Check the fridge before the jar
El Cronista is clear on one point: “coffee does not eliminate the cause of bad odors.” Before setting out the jar, look for the source. Throw out anything spoiled or past its date, then wipe up spills and clean the drawers, the shelves and the rubber door seals. Only then does the jar have a chance to keep things fresh.
The limit
How well it works depends on how much coffee you use, how much moisture is in the fridge and what’s causing the smell, El Cronista notes. No study cited by either site measures the effect. And the jar leaves a light coffee scent of its own: Apartment Therapy’s writer says you should “enjoy at least the slightest smell of coffee” to like the result. If you don’t, the box of baking soda is still there.
Coffee grounds have other uses around the house: here’s the two-ingredient paste that clears a smelly sink. For the fridge itself, see why people are placing aluminum foil on refrigerator shelves, and the sheet of paper test technicians run on the door.
Dry grounds, an open jar, a clean fridge. That’s the trick.
