Foods You Can and Can’t Put Down the Garbage Disposal
This appliance can handle many types of foods—but don’t treat it like a trash can
The term “garbage disposal” is a bit misleading, considering it’s designed to dispose of food waste exclusively. We trust you’re not running plastic, glass, and metal through your disposal, but there are also some less-than-obvious foods that land on the No list below.
We put garbage disposals to the test in our lab, but we also spoke with disposal manufacturers and experts in plumbing and wastewater treatment to nail down a definitive list of what you can and can't put down the disposal. We also surveyed 1,040 Americans who own and use garbage disposals on what they routinely send down the drain. Judging by the responses, some of the “yes” and “no” foods might surprise you.
Here's a quick reference guide. And for all the details, read on below.
Foods You Can’t Put Down the Disposal
For the most part, garbage disposals can grind pretty much anything you throw at 'em. Your plumbing, however, is another story. Turns out, that bacon grease you poured down the drain awhile back could be the beginning of a clog down the road.
Fats, oils, and grease. All our experts agreed that fats, oils, and grease (what the industry refers to as FOGs) should never go into your disposal—or any drain for that matter.
“They might start out in a liquid state but those materials will congeal and eventually cause clogs further downstream in the water system,” says David Duest, director of the Deer Island Treatment Plant in Boston.
Foods You Can Put Down the Disposal
Basically, all other foods—from peach pits to corn cobs to cooked steak—can be ground up and washed down the drain.
But according to our survey, there are a handful of foods homeowners didn’t realize they can put down the disposal. Only 9 percent of respondents said they put small bones in their disposals. But manufacturers insist it’s perfectly safe.
“People worry that bones will break the disposal’s blades—but food waste grinders actually don’t have blades,” says InSinkErator’s Schultz, explaining that an impeller uses centrifugal force to spin food up against a stationary grind ring. “What you may notice with entry-level disposals is they can be quite loud and vibrate a lot when grinding bones, but they’ll still pulverize them into small particles.”
In CR’s garbage disposal lab, we test each model with heavy-duty beef rib bones to really challenge them, and indeed, they were all able to adequately grind up bones. If you plan to regularly grind bones (nothing larger than a rib bone) and other heavy-duty foods, like fruit pits and corn cobs, opt for a garbage disposal with more horsepower.
“The higher the horsepower, the more difficult foods it can process,” says Moen’s Wiegand. Disposals with 1 hp can tackle bones without rattling the sink or making it feel like your ears are bleeding.
Plumbers are a bit more cautious when it comes to putting bones into the disposal, however, also because it comes down to what your home's pipes can handle.
“Even small and medium-sized chunks of bone and other hard foods potentially increase the odds of a clog in your drainage system,” says Abrams. The risk level depends on the age and condition of your pipes. “Large food debris might not present a problem in a newer home with a network of pristine PVC drain pipes, but clog risks go up substantially if you have rugged old cast-iron drain pipes.”