Remove Burnt Grease and Food Debris From Sponges by Soaking in Salt Water.
After scrubbing with the rough side of the sponge, there is a good chance that a bunch of nasty food debris will get stuck there. Dampen a little salt water and it will flake off and your sponge will look almost like new.
The sponges seem to absorb more water. They take away bits of food and burnt fat. This video from YouTube channel HouseholdHacker – around 1:20 – shows you that a good soak in salt water can help get rid of this unpleasant substance without starting to smell like your sponge. Add 1/4 cup salt to about two cups of water, toss in a sponge and let sit overnight. All this dirt should disappear or be easily removed in the morning. Just in case, make sure you have another sponge while you soak it. Replacing a sponge is not too expensive, but why waste money when you can revive the existing ones?
7 Salt Life Tips You Should Know About | Youtube