Remember that blue Jell-O the kids made, when was it, back around Thanksgiving? That blue Jell-O that spilled in the back of the refrigerator and has left a stain there ever since? A neon-colored smear that's a constant reminder that it's time to clean your fridge?
A frost-free refrigerator should be cleaned every four to six months. A manual-defrost fridge should be cleaned whenever the freezer needs defrosting (when the frost gets to be a half-inch thick).
Here's how to achieve that just-like-the-day-it-was-delivered state once again - or something closer to it - using advice gleaned from Home Comforts: The Art & Science of Keeping House by Cheryl Mendelson, Consumer Reports, the DIY Network, and HGTV:
Throw out food past its prime. That includes leftovers if they're more than three days old. Check milk and other containers, and throw out anything past its "use by" date.
(This is not to be confused with the "sell by" date - foods are good for several days past that. The "best by" date is somewhere in the middle. Most foods are edible past their "best by" dates, but might not be at their freshest.)
Remove what's left. Put nonperishable foods, such as fruits and veggies, on the countertop. Group foods that should stay refrigerated onto as few shelves as possible.
Take out the remaining shelves and drawers and wash them in warm - not hot - soapy water. (Cold glass shelves can crack in hot water, and some plastics might warp.) Rinse and let dry. Wipe one shelf dry, put it back in the fridge, and move the perishable foods onto it; then wash the remaining shelves.
Wash inside. First, unplug the refrigerator. Fill a bucket with warm, soapy water and a little baking soda (4 tablespoons per quart). Starting at the top, wipe down the walls, then the door. Use a nylon scrubber for stuck-on gunk. Use a toothbrush or a toothpick to clean out cracks. Be sure to clean the rubber gasket around the door, too. Rinse with clean water and wipe dry.
Repeat with the freezer. First, toss any foods that are no longer recognizable or that are covered in ice. In general, meat and poultry will keep frozen six to 12 months; fish, six months; fruit, four to six months; vegetables, eight months. (You remembered to label and date everything before you put it in the freezer, didn't you?) Pack the frozen foods in a cooler while you clean.
Plug the unit in again. Don't forget this step. Then replace the food - put the oldest packages at the front of the shelves, so you'll use them first. Don't put foods back into the freezer until it has been running for at least 30 minutes.
Clean the outside. First, dust the top (and resolve to do it way more often). Wipe down the exterior with more warm, soapy water, or you can use baking soda and water. To shine a stainless-steel door, try rubbing alcohol or a product specially formulated for stainless steel.
Clean the drip pan. If your refrigerator has one, it needs to be kept clean, because mold likes to grow here. Remove the pan, wash in hot water, and sanitize with 1 teaspoon of chlorine bleach in 1 quart of water.
Vacuum the condenser coils. These are usually underneath, behind the kick plate or grill. Dust on the condenser can cause your fridge to slow down or even stop working. Check the owner's manual for how to get to the condenser, and dust with a bottle brush, a rag on the end of a yardstick or the vacuum cleaner.
To absorb yucky fridge odors, try any of these:
An open box of baking soda.
Activated charcoal (try an aquarium store).
Vanilla extract (the imitation stuff is fine) on a cotton ball.
Fresh ground coffee.
And while you're in maintenance mode, if you have a filter on the water line that goes to your ice-maker/water dispenser, check to see whether it's time to change it.
Buy a refrigerator-freezer thermometer (try the hardware store) and check your fridge's temperature. The refrigerator should be 32 to 40 degrees; the freezer should be zero degrees.
And make sure the door seal is tight. Place a lit flashlight inside the fridge, turn off the room lights and check for any leaks in the insulation.