Your Kitchen Sponge Is Dirtier Than You Think—Here's How To Clean It
A kitchen sponge is one of the dirtiest items in your home. Learn how to clean a kitchen sponge and tell when it's time to toss it.
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One of the hardest working tools in the kitchen is a sponge. You grab it to wipe a counter, wash a dish, and scrub the sink. But, how often do you clean the sponge? Just think of all the bits that are stuck in the spores just waiting as food for bacterial growth. We have several common methods you can use to clean a sponge and the best advice on when it's time to replace it to keep your kitchen healthy.
Related: How Often To Clean Every Surface Of Your Your Kitchen, According To An Expert
Understanding the Need for Cleaning Sponges
According to the National Science Foundation, a kitchen sponge can be one of the dirtiest items in your home. Most sponges never dry out completely and have nooks and crannies to trap debris, making them the perfect breeding ground for bacteria, including E. coli, that can lead to contamination of surfaces and food products. After just two weeks, a sponge can have around eight million bacteria. When we use a dirty sponge, the bacteria is transferred to our hands and the food we are preparing or eating.
Needless to say, a sponge should be cleaned at least once a day, preferably after every use. It's best to use different sponges for different tasks. Using the same sponge to wipe counters or a floor spill and then to wash dishes increases the chance of bacterial contamination. Sponges should be replaced at least every two weeks; weekly replacement is even safer.
Methods for Cleaning a Sponge
The following four methods are recognized as the most effective for killing harmful bacteria in sponges. If none of them appeal to you, the sponge should be replaced.
Using the Microwave
The U.S. Department of Agriculture finds that microwaving a kitchen sponge kills 99.99 percent of the bacteria. Do not microwave sponges that have a metallic component.
Materials Needed: Sponge, Water, Microwaveable bowl, Microwave, Drying rack
Step 1: Rinse out any obvious debris from the sponge and saturate it with water.
Step 2: Place it in a microwave-safe bowl.
Step 3: Microwave for one minute.
Step 4: Allow the sponge to cool (10 to 15 minutes) before wringing out the water.
Step 5: Place the sponge in a rack to air-dry.
Using the Dishwasher
According to USDA, cleaning a sponge in the dishwasher kills 99.98 percent of the bacteria.
Materials Needed: Sponge, Dishwasher detergent, Dishwasher
Step 1: Place the sponge on the top rack of the dishwasher.
Step 2: Add dishwasher detergent and run the hottest, longest normal cleaning cycle including the dry cycle.
Using Boiling Water
Materials Needed: Sponge, Stovetop, Pan, Water, Drying rack
Step 1: Place at least two cups of water in a pot.
Step 2: Bring the water to a rolling boil on the stovetop.
Step 3: Add the sponge.
Step 4: Boil the sponge for 5 minutes.
Step 5: Allow the water and sponge to cool.
Step 6: Wring out the sponge and place it in a drying rack to air dry.
Using Chlorine Bleach
Materials Needed: Sponge, Concentrated chlorine bleach, Measuring spoon, Glass or plastic bowl, Warm water, Drying rack
Step 1: Mix a solution of one-half teaspoon of concentrated chlorine bleach and one quart of warm water in a glass or plastic bowl.
Step 2: Add the sponge and be sure it is fully saturated.
Step 3: Allow the sponge to soak for one minute.
Step 4: Wring out the sponge and place it in a drying rack to air dry.
When to Replace a Sponge
Sponges should be replaced when they become damaged or develop a bad odor. A damaged or torn sponge offers more spots for bacteria to gather. A bad odor means that a heavy amount of bacteria is present.
Even if you have cleaned the sponge daily, it looks okay and doesn't smell, every kitchen sponge should be replaced at least every two weeks. Fortunately, most kitchen sponges are made of cellulose or wood pulp that will biodegrade over time.
Tips for Maintaining Sponge Hygiene
Use different sponges for each kitchen cleaning task. Color coding is an easy way to keep sponges separate.
Rinse and clean a sponge after every use.
Use a dish drying rack for sponges so they air dry quickly.
Never leave a sponge in the sink or a spot where it remains damp.
Frequently asked Questions
Are there any sponges that are more resistant to bacteria?
There are antimicrobial sponges on the market made from quick-drying synthetic fibers and treated with organic active ingredients such as Quaternary Ammonium Compounds (QUATs) or one of three inorganic active ingredients: silver phosphate glass, zinc pyrithione, or copper.
