Things You'll Need
The sour smell of spoiled milk can permeate everything in your refrigerator, even after the offending liquid is discarded. If the milk was spilled, the puddle may have seeped into a hard-to-see area where it then spoiled and began to produce its foul odor. Sour milk smells are completely removable, but it may require some effort and time, depending on how severe the odor and how long it's been permeating the refrigerator's interior.
Remove all items from the refrigerator. Place them in a second refrigerator, if available, or in a cooler with ice so they don't spoil as you clean.
Take the shelves out of the refrigerator. Remove the vegetable crisper drawers and the drip tray from the bottom of the unit.
Wash the shelves, drawers and drip tray with hot, soapy water. Rinse with clear water and wipe dry with a clean towel.
Wipe out the interior of the fridge with hot, soapy water. Rinse with clear water.
Soak a rag with white vinegar. Wipe down the interior of the refrigerator and the removed shelves and drawers with the vinegar-soaked rag. Vinegar kills any odor-causing bacteria that remain after washing. The vinegar smell dissipates within a few hours.
Place the shelves, drawers and drip tray back in the refrigerator. Set an opened box of baking soda in the back of the fridge to absorb any remaining odors before replacing the food items in the refrigerator.
If the smell persists, fill the refrigerator with crumpled up newspaper for two to three days. Discard the newspaper once it absorbs the remaining odors. You'll need an alternate place to store your food in the meantime.