How to Clean Aluminum After It Has Been in the Dishwasher & Turned Dark

The affordable cookware conducts heat well, but aluminum can become discolored when it is exposed to certain chemicals and minerals. Placing aluminum cookware in a dishwasher can cause a reaction that darkens the pan or pot. The high heat of the appliance paired with the mineral content in the water and chemicals in the detergent lead to blackened aluminum cookware.

Baked chocolate brownies on a baking tray placed on a wire cooling rack.
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The affordable cookware conducts heat well, but aluminum can become discolored when it is exposed to certain chemicals and minerals.

There are a number of natural products that can shine up an aluminum pan. Lemon juice, cream of tartar and vinegar all make great work at removing dark stains from aluminum cookware. They are fast and effective and don't negatively affect the item.

Dishwashers and Aluminum Cookware

Putting stainless steel in the dishwasher or favored aluminum pans can spell disaster if the item isn't pretreated to go in the appliance. In general, metal in the dishwasher has a difficult time. The forceful jets of water, harsh detergents and clanging around with other dishes can cause discoloration, nicks and pock marks on the surface of the cookware.

Aluminum in the dishwasher isn't always a good idea. Any aluminum pot, baking sheet or roasting pan that has not been anodized can become pitted or otherwise corroded by the harsh detergent used in the major kitchen appliance.

White spots can bloom on the surface of the aluminum cookware due to the alkalinity of the detergent. In general, it's best to handwash aluminum cookware. If the cookware has been darkened after a trip through the dishwasher, the best way to bring it back to a semblance of its former condition is to use natural astringents and cleaners.

Dishwasher Safe Symbol

The symbols on dishes are there to help keep them in good condition through any type of heat or cleaning. Along the rim or base of a pan, utensil, pot or dishware are symbols that are meant to relate whether or not the item can be placed in the dishwasher and come out unscathed. Symbols are not internationally accepted, so you may want to handwash any item you are considering putting in the dishwasher if it doesn't have any clear symbols. Look for the dishwasher safe symbol before placing any food-safe item, aluminum or otherwise, in the appliance.

Dishes in a shower of slanted straight lines means that the product can safely run through the dishwasher cycle on the top rack only. A plate in a rack with water drops slanted over the top in a small rectangle means that the dish or item can withstand the high heat of a typical dishwasher cleaning cycle.

The international symbol for food safe is a wine glass and fork. This means it can be used to hold food meant to be eaten.

How to Clean Aluminum Cookware

Begin with water. Fill the damaged aluminum cookware until it is nearly brimming. It needs enough rom to have the water boil without the contents spilling over onto the stovetop and creating a bigger mess.

For each quart of water, add 3 tablespoons of lemon juice, cream of tartar powder or white distilled vinegar. Bring the solution up to a boil and let it roil for a good 10 minutes before removing it from the heat and draining the pan.

Grab a steel wool soap pad soaked in warm water to remove any layers of minerals that have lifted from the surface of the aluminum pot or sheet pan. Rinse it thoroughly to remove any signs of the soap reside and dry it so that no moisture clings to the newly cleaned surface.


Kimberley McGee

Kimberley McGee

Kimberley McGee is an award-winning journalist with 20+ years of experience writing for a variety of clients, including The New York Times, Las Vegas Review-Journal Home section and other national publications. As a professional writer she has researched, interviewed sources and written about home improvement, interior design and related business trends. She earned a B.A. in Journalism from the University of Nevada, Las Vegas. Her full bio and clips can be viewed at www.vegaswriter.com.