Skip to main content
Menu
Search
Menu
Close

We make mistakes so you don’t have to.

Try CooksIllustrated.com Free for 14 Days

Email is required
How we use your email address

How to Clean a Kitchen Sponge

By Kate Shannon Published

A dirty kitchen sponge can breed bacteria and contaminate your kitchen. Here are three ways to clean a kitchen sponge—and one thing you should never do.

When we do the dishes, we generally wring out the kitchen sponge after use. But we’ve all lived with roommates or family members who do the opposite. They wash their dishes and drop the sponge in the bottom of the sink, where it sits in a puddle and never fully dries out.

Sponges have lots of little crevices and tend to be both warm and wet—an ideal environment for bacteria to flourish. So we were curious: Are those soggy sponges harboring more bacteria than sponges that we wrung out after use? We decided to find out.

Do Wet Kitchen Sponges Contain More Bacteria?

For two weeks, we used six identical sponges to clean up dishes, carefully measuring the amount of food, as well as the temperature of the water and the amount of soap we used. After each use, we squeezed the water out of three of the sponges and placed them in a dish rack so they could air-dry. We left the other three wet and set them in open plastic bowls, mimicking sponges that had simply been dropped and left in a damp place such as the bottom of the sink. After the two weeks, an independent lab measured the total bacterial count of each sponge in colony-forming units per milliliter (CFU/mL)—and the difference was staggering.

The sponges that had been left wet averaged more than 500,000 CFU/mL, while the wrung-out sponges came in at just 20 CFU/mL. The lab did not differentiate species of bacteria, so we don’t know if any of this bacteria was potentially harmful. But the conditions for growing good bacteria and bad bacteria are the same, and the results were clear: Wet sponges really do harbor more bacteria.

How to Sanitize a Kitchen Sponge

From now on, we’ll always wring out sponges and store them in a place where they can dry between uses. But even a clean kitchen sponge can still get grimy. Worse, it can stay damp on the inside even when it looks and feels dry on the outside.

To learn how to clean them, we turned to NSF International, a public health and safety organization that develops standards and certifications. Lisa Yakas, a microbiologist and home product certification expert at NSF International, proposed three methods:

METHOD 1: Dampen your sponge and microwave it for at least 2 minutes.

METHOD 2: Run your sponge through your dishwasher on a setting that reaches at least 155 degrees and has a heated dry cycle (sometimes called sani-rinse, sani-wash, or sanitation cycle), preferably every time you run your dishwasher.

METHOD 3: Submerge your sponge in a bleach solution (¾ cup of bleach for every gallon of water) for at least 5 minutes and then rinse it thoroughly.

After using any of these methods, allow the sponge to dry completely before using it again, ideally in a dish rack or a container that allows air to circulate around all surfaces of the sponge.

A good rule of thumb . . . is to replace your sponge every one to two weeks, cleaning it regularly in between uses, and storing it someplace where it can dry.

Does Sanitizing a Sponge Kill All the Bacteria?

The experts we spoke to insisted that regularly cleaning a sponge is essential. But it’s not going to remove every bit of bacteria or make your sponge last forever. Some studies show that these methods are effective, while others indicate that they remove no more than 60 percent of bacteria. At home, there’s just no way to know how much bacteria was on your sponge to begin with or how much has been killed. Neither at-home sanitization method will dramatically extend the life of your sponge. A good rule of thumb, according to Yakas, is to replace your sponge every one to two weeks, cleaning it regularly in between uses, and storing it someplace where it can dry.

The Best Kitchen Sponge for Home Kitchens

There’s one more way to guarantee that you get great results from your kitchen sponge: Buy a good one. We recently tested 10 different styles and were amazed by the differences. Some slipped and skid around a pan instead of scraping off cooked-on food. Some were too floppy or small to use comfortably. One became matted and grimy with leftover food particles, which was unpleasant to use and certainly didn’t feel clean. Our favorite, the O-Cedar Scrunge Multi-Use Scrubber Sponge, was a real improvement over the traditional blue sponge. Instead of a relatively smooth abrasive surface, its scrubber is slightly gritty and has bumps and valleys that really nudge off food residue with minimal effort. It’s also relatively inexpensive, about $10 for a six-pack, so you can replace your sponge regularly without breaking the bank.

The Best Kitchen Sponge

Equipment Review Kitchen Sponges

Doing dishes is a dirty job. We found the kitchen sponges that make it easier (and the ones you should avoid).

Equipment Review Innovative Dish Drying Racks

While dish racks are not the most exciting kitchen purchase, they are an essential for drying hand-washed dishes. We put five innovative models up against a basic basket-and-mat system.

Leave a comment and join the conversation!

0 Comments
Read & post comments with a free account
Join the conversation with our community of home cooks, test cooks, and editors.
First Name is Required
Last Name is Required
Email Address is Required
How we use your email?
Password is Required
JC
JOHN C.
16 days

Absolutely the best chicken ever, even the breast meat was moist! It's the only way I'll cook a whole chicken again. Simple, easy, quick, no mess - perfect every time. I've used both stainless steel and cast iron pans. great and easy technique for “roasted” chicken. I will say there were no pan juices, just fat in the skillet. Will add to the recipe rotation. Good for family and company dinners too. I've done this using a rimmed sheet pan instead of a skillet and put veggies and potatoes around the chicken for a one-pan meal. Broccoli gets nicely browned and yummy!

Absolutely the best chicken ever, even the breast meat was moist! It's the only way I'll cook a whole chicken again. Simple, easy, quick, no mess - perfect every time. I've used both stainless steel and cast iron pans. great and easy technique for “roasted” chicken. I will say there were no pan juices, just fat in the skillet. Will add to the recipe rotation. Good for family and company dinners too.

MD
MILES D.
JOHN C.
9 days

Amazed this recipe works out as well as it does. Would not have thought that the amount of time under the broiler would have produced a very juicy and favorable chicken with a very crispy crust. Used my 12" Lodge Cast Iron skillet (which can withstand 1000 degree temps to respond to those who wondered if it would work) and it turned out great. A "make again" as my family rates things. This is a great recipe, and I will definitely make it again. My butcher gladly butterflied the chicken for me, therefore I found it to be a fast and easy prep. I used my cast iron skillet- marvellous!

CM
CHARLES M.
11 days

John, wasn't it just amazing chicken? So much better than your typical oven baked chicken and on par if not better than gas or even charcoal grilled. It gets that smokey charcoal tasted and overnight koshering definitely helps, something I do when time permits. First-time I've pierced a whole chicken minus the times I make jerk chicken on the grill. Yup, the cast iron was not an issue.