Aluminum is a light-weight metal with a bright silvery luster. Its affinity for oxygen makes it resistant to corrosion and attack by most chemicals, and small amounts of other metals can be added to aluminum to make harder alloys for most uses. Most aluminum used in visible parts of appliances is also lacquered or otherwise coated, anodized, or painted.
Aluminum exposed to air does grow its own thin oxide coating very fast. This hard, dark gray coating protects the metal, and it's found on all bare aluminum surfaces, including utensils. "Anodizing" is a commercial process that thickens this coat, often colors it, and stops it from rubbing off. A special anodizing process produces a very hard, dark gray finish on professional cookware. However, while aluminum is durable and requires little maintenance to keep a good finish, there will be times when your pieces need cleaning and repair. Read on to learn more about how best to take care of your aluminum.
Protect Against Blemishes and Stains
Proper care depends on the product made from aluminum. Lacquers or waxes can protect against weathering and corrosion, but they cannot be used on objects in contact with food. Brighten aluminum utensils instead by cooking acidic foods such as tomatoes, apples, or rhubarb; you can also boil one to two teaspoons cream of tartar per quart of water or two tablespoons vinegar per quart of water for 10 minutes in a pan.
Prevent discoloration on the bottom of double boilers or egg poachers by adding one teaspoon vinegar or 1/4 teaspoon cream of tartar to the water in the bottom pan.
Remove stains from the outside of aluminum pans with silver polish, or mild, nonabrasive cleaner. Soap-filled steel wool pads only scratch the outside surface, so use only when removing burned-on food or grease is more important to you than the scratched pan.
Removing Food and Grime
Remove hard water mineral deposits (lime scale) from tea kettles where they have become crusted by boiling equal parts of vinegar and water for several minutes and letting the solution stand an hour or so. The process may have to be repeated in severe cases. Rinse the kettle with plain water before you use it again.
For food debris, start by filling the object with hot water and letting stand one hour. Scrape off as much food as possible with a dull item such as a wooden spoon, half of a clothespin, a plastic spatula, or a plastic sponge. For any tough spots or residue that remains, use a soap-filled steel wool pad. Grease build-up can be easily taken care of with a soak in very hot water with detergent. Follow it up by scouring the piece with your steel wool.
Use a mild detergent and warm water when possible to clean. Alkalis, even baking soda, can discolor aluminum so avoid these for cleansers. If you need to try a stronger cleaner, pre-test it on a hidden place to be sure it cleans satisfactorily without damaging the aluminum. Always follow directions on the product label for aluminum to the letter.
Be cautious about using abrasive cleaning objects (scouring powders, steel wool, abrasive polishes, etc.) as they may scratch the surface; painted or anodized aluminum surfaces will be permanently damaged. Also, do not clean aluminum when it is too hot to touch, or if temperatures go below 50 degrees Fahrenheit.
For any outdoor surfaces, remove bugs, sap, tree seeds, etc. as soon as possible, as they harden with exposure to sunlight and heat, and will be tougher to get off the longer they sit. Suitable solvents will remove tar and similar substances, but test the solvent first if the aluminum is painted to be sure it doesn't also remove the paint. Follow label precautions when using solvents—make sure there’s no heat source in the area and have sufficient ventilation before starting.