Removing Burnt-On Oil
We tested four methods for removing burnt-on oil to see if we could really do it without resorting to harsh chemicals.
In the test kitchen, our stainless pots and pans get a daily workout in many high-heat applications. Over time, a layer of baked-on oil and grease often develops that is difficult to remove without the aid of harsh, toxic cleansers. This scorched residue is the result of heating oil or other fats to high temperatures. When oil or other fats are heated to or above their smoke point, their triglycerides break down into free fatty acids, which then polymerize to a resin that is insoluble in water.
Is there a way to remove this residue without resorting to caustic chemical cleansers? To find out, we abused four stainless steel skillets by slicking them with several tablespoons of oil and heating them until it smoked and burned onto their surfaces. To further solder this resin to the pans, we then baked the skillets in a 500-degree oven for a few hours.
To rehab them, we let the cooled pans sit overnight with the following treatments: one coated with a thick paste of baking soda and water, one filled with straight vinegar, one soaked in a 20 percent vinegar solution, and one soaked in hot, soapy water. (Baking soda, vinegar, and soap all contain compounds that help to dissolve the fatty-acid resins and help them release from the metal surface.) None of these treatments was 100 percent effective; we still needed scouring powder and a metal scrubbing pad to remove the most tenaciously burnt-on bits of oil. But somewhat surprisingly, the hot, soapy water was the best treatment of the bunch, loosening the residue enough so that it required the least amount of elbow grease and a minimum of scratching of the pan’s finish to fully release.