While a ceramic Crock-Pot offers a handy way to cook all sorts of dishes, it may develop a film or residue that doesn't always wash away with soap and water. The darker the Crock-Pot liner, the more obvious the white residue. While it may look alarming, this film is just a mineral deposit left from evaporating water in the Crock-Pot. The solution: regular household vinegar.
Removing Crock Film
If you've already washed the ceramic Crock-Pot but the ceramic insert still has a white or chalky residue inside, it's time for a mineral-busting treatment. Wet a sponge, then pour a tablespoon or so of vinegar on it. Wipe down the inside of the Crock-Pot with the vinegar solution.
Undiluted vinegar comes in handy for more stubborn film. Spray white vinegar directly on the mineral spots or film inside the Crock-Pot. After 10 minutes or so, wipe the vinegar away with a clean, damp sponge. Rinse the Crock-Pot insert in the sink, then allow it to air-dry. If your home has hard water, air-drying kitchenware may leave them riddled with water spots, also known as mineral deposits. If this is the case, towel-dry the Crock-Pot insert instead.
To help prevent white film in the future, rinse and wipe the Crock-Pot after use, even if you don't have time to wash it yet. Don't leave water sitting inside the Crock-Pot for extended periods of time, as even plain tap water can cause film or residue.
Steaming Vinegar Treatment
If some of the white residue remains even after wiping the crock insert with vinegar, a steam cleaning helps eliminate the rest of the film. Pour an inch of distilled water into the Crock-Pot. While tap water can be used, it may leave behind more mineral deposits. Add 1/2 cup white vinegar for a small cooker or 1 cup for a slow cooker that holds 5 quarts or more.
Heat the Crock-Pot on low with the lid on. After 30 minutes, note whether steam coats the inside of the lid. If not, turn the heat to medium. After 1 hour total heating time, turn the Crock-Pot off. Once the liquid is cool enough to touch, wipe down the inside of the slow cooker with a sponge or dishcloth dipped into the liquid. Use the remaining liquid to wipe mineral deposits off chrome fixtures in the kitchen.
Add Bubbling Baking Soda
A bubbling reaction between vinegar and baking soda helps remove stubborn film and cooked-on food residue. Add an inch of water, 1/2 cup white vinegar and 1/2 cup baking soda to the slow cooker, pouring the baking soda slowly so it doesn't fizz over the rim of the cooker. Place the lid on the slow cooker and set it to low heat. After an hour, wipe the inside of the slow cooker down with the foamy solution.
For stubborn baked-on residue, sprinkle a little more baking soda or even table salt onto the sponge, using the material as an abrasive to help remove the residue. Dump the liquid into the sink, then wash the ceramic insert by hand with soap and water or in the dishwasher.