Why Do Aluminum Pans Get Discolored In the Dishwasher?

Why Do Aluminum Pans Get Discolored In the Dishwasher

Dishwashers are great for cleaning almost all dishes, pots and pans safely. However, some pans can’t be washed in the dishwasher and can suffer from possible discoloration and stains.

Aluminum pans can suffer from some serious damage if placed in a dishwasher. There are two main reasons behind this— the intense heat the dishwasher uses to clean dishes and the corrosive dishwater detergent used by the dishwasher. The surface of an aluminum pan is too delicate and usually can’t withstand the combination of these two factors within the dishwasher.

Many dishwashing companies have now been asked to eliminate the use of phosphates in their mixture as per the legislation in many states. A huge benefit of phosphates being added in dishwashing soaps is its ability to protect the surface of metals.

The elimination of phosphates from the production process of dishwashing soaps results in quicker discoloration of aluminum plans.

Most aluminum cookware is better off being washed by hand to prevent it from changing its color and feel.

Types of Aluminum Cookware

Aluminum cookware has been around for a while. It has significantly improved and upgraded from its early days. It is one of the most popular types of cookware as more than 50% of all the cookware sold is made of aluminum.

Aluminum cookware is the second-best in terms of conductivity. When purchasing this type of cookware, you should definitely read the label.

There are various types of aluminum cookware available in the market, such as pressed, cast or anodized.

Pressed Aluminum

Pressed aluminum cookware is the cheapest of the lot. It is popular for its screw-in handle and thin construction. The majority of aluminum utensils are made using this material.

However, these utensils don’t last for long as the handles get loose or completely fall off very quickly. Pressed aluminum cookware suffers damage very quickly and is probably prone to immediate damage if it is lodged in a dishwasher.

Cast Aluminum

Manufactured in a slow, yet costly process, cast aluminum is worth every penny spent on it. The final product is thicker than pressed aluminum cookware.

The bottom of a cast aluminum pan is thicker than the sidewalls for extra protection. Cast aluminum pans have improved heat retention because it’s more porous than pressed aluminum.

Anodized Aluminum

Anodized or hard-anodized aluminum cookware is top-notch cookware. This is the kind everyone should be opting for. This type of aluminum cookware is resistant to scratches and does not allow food to stick to it. The surface of anodized aluminum pans is harder than steel.

This type of cookware mostly costs more than all types, but it’s worth the money. Anodized aluminum falls under the class of stainless steel, cast iron and copper cookware— all of these are of superior quality. Anodized aluminum pans can be easily recognized by their grey finish.

However, this grey finishing on the pans is extremely prone to damage in the dishwasher. Cast aluminum cookware such as pots and pans are thicker and heavier than pressed aluminum cookware, but they also tend to have a delicate finish, which makes it completely unsuitable for dishwashers.

Dishwashers and Aluminum Cookware

Adding stainless steel cookware or aluminum pans in the dishwasher puts you on a path to disaster, especially if the item isn’t pretreated to be washed in a dishwasher.

Any aluminum pot, baking sheet or roasting pan that has been anodized can often become pitted or can corrode due to the harsh detergent properties.

The alkalinity of the detergent can cause white spotting on the surface of the aluminum cookware. If the cookware has been darkened after being in the dishwasher, then the best way to bring it back to its normal state is by using natural astringents and cleaners.

Dishwasher Safe Symbol

On your cookware and dishes, you’ll be able to spot symbols that imply that the dishes are safe from any type of heat or cleaning. Along the rim or base of an aluminum pan, pot or utensil, you can find symbols that signify if the cookware is dishwasher safer or not.

Based on that, you can wash your cookware. Since not all symbols are internationally accepted or recognized, you might want to hand wash any cookware items if you’re still unsure about whether they belong in the dishwasher or not.

A symbol of a shower with slanted straight lines implies that the pot or pan can only be run through the dishwasher cycle on the top rack only.

Dishes or cookware with a symbol of a plate in the rack with water drops slanting over the top in a small rectangle shape implies that the dish can easily bear the high heat of a normal dishwasher.

Remember to keep these signs in mind before you add your cookware in the dishwasher.

Advice on Putting Aluminum Pans in the Dishwasher

Before throwing a pan in your dishwasher, make sure to read the manufacturer’s instructions, given on the packaging, to know if the pans are safe or not for dishwashers.

Always follow the manufacturer’s recommendations as this will save you money in addition to protecting other dishes in the dishwasher. The damage done to aluminum pans may not be very evident at first as it takes time for the surface to break down and for tarnish to form on it.

This means that if you want, you can wash the aluminum pan once in the dishwasher and decide if it’s safe or not. However, it’s just better to avoid doing so.

The rule of thumb is to not place any sort of aluminum cookware such as pans in the dishwasher.

Regardless of the type of aluminum, the dishwasher will most definitely cause damage to them. In case you don’t care about damaged flimsy aluminum pans, still don’t put them in the dishwasher as they harm the items and dishes near them as they move around during the washing cycle.

On the other hand, stainless steel pans and cookware can be put inside the dishwasher, but don’t forget to check the manufacturer’s instructions beforehand. Try rinsing the pans if you’re not running it in the dishwasher immediately.

The Environment of the Dishwasher

Dishwashers can heat water up to more than 140 degrees. This environment created inside a dishwasher is necessary for the dishes to be washed properly.

The heat inside the dishwasher is mandatory for melting the detergent and removing any grease and grime that is stuck to the dirty dishes.

The detergent used for dishwashing also contains very harsh chemicals to help clean the dishes more effectively.

When the hot water is combined with this harsh dishwashing detergent inside the dishwasher, it leaves cloudy stains on aluminum pans that are very hard to remove.

Proper Cleaning of Aluminum Pans

When aluminum cookware such as pots or pans are being washed in a dishwasher, they can react and darken because of the high mineral content of the hot water, the harmful chemicals of the detergent, or the high heat from the dish dryer.

Aluminum pans or cookware that aren’t safe for dishwasher safe should be washed in the kitchen sink with mild dishwashing detergent and warm water.

You should avoid the use of any abrasive pads or hard scrapers on the aluminum pans as they can damage them. Unless approved by the manufacturer, these pads or scrapes can scrape up or scratch off the metal and non-stick coatings.

The pans need to be rinsed thoroughly after cleaning.

In case your aluminum pans meet a sad fate and get all tarnished, you can use natural elements such as lemon juice, vinegar or tartar cream to get rid of the discoloration and get fast and great results without any damage to the metal.

Acidic items such as lemons are a great option to get rid of tarnish from aluminum pans. Here’s how you can clean your damaged aluminum pan after it has been in the dishwasher:

  • Initiate the process with water. Fill the aluminum pan or pot with water until it’s nearly brimming. Just make sure you spare just enough room so that the water doesn’t boil and spill over onto the stovetop as this will create a big mess.
  • For every quarter of water, add three tablespoons of lemon juice, white vinegar, or cream of tartar. Let the solution boil for about 10 minutes before removing it from the stove and draining it.
  • Take a steel wool pad that has been soaked in warm water. Now, use that to get rid of any mineral layers that have lifted from the surface of the pot or pan due to the boiling process. Rinse the aluminum pan or pot thoroughly to get rid of any remaining soap residue.
  • Take a clean cloth and dry up the pan to avoid any moisture from clinging on to it.

You can also apply the metal polishing paste on the oxidized area of the aluminum pan. Not only will it rid the pan of oxidation, but it will also make the surface of the aluminum pan shiny.

Just apply some to the oxidized area and let it work its magic.

Problem Stains on Aluminum Pans

If the pans are burnt with food or grease, you need to remove as much food as possible using a spoon or spatula. A wooden spoon is a great choice for those food items that are really hard to scrape off.

Once you are done the scraping, fill the pan with hot water and allow it to remain there for about an hour. End the cleaning process by washing the pan with warm soapy water and a sponge.

Once that’s over, wipe the pan with a clean cloth to prevent spotting over time.

Additional Tips when cleaning aluminum pans:

  • In case you can want to wash your aluminum pots and pans in the dishwasher while avoiding stains, you can try changing up your dishwashing detergent. You can look for one that is bleach-free and eco-friendly. You can find such detergents at a healthy food or organic store. A detergent packed with enzymes is a good option for you to use.
  • The best way to wash aluminum cookware in order to avoid getting any stains is by washing it by hand in the sink. Make sure that you choose a pH-neutral dishwashing liquid. A majority of dishwashing liquids are alkaline, which can darken the aluminum pans.
  • Check your anodized aluminum pan and see if you notice traces of gold or copper. In case it appears to be copper or gold, then it won’t be safe for washing in the dishwasher as there is a high chance that the coating will be removed.
  • Even though salt can be used as a mild abrasive for cleaning as a substitute for a piece of wool, we suggest that you be careful. Salt can only be used on certain items and should not be used on aluminum cookware as it can cause some serious pitting. Avoid any tips that tell you to wash your aluminum pan with salt.
  • Aluminum cookware is affordable and a great conductor of heat, but it can suffer from discoloration if it is exposed to certain chemicals, minerals, and conditions. Placing aluminum pans in a dishwasher can have a detrimental effect on it. The high heat of the dishwasher along with the mineral content of water can lead to darkened aluminum cookware.

The Bottom Line 

The bottom line is that aluminum pans can suffer a detrimental fate if they are put in a dishwasher.

Cookware made of anodized aluminum is rather expensive, and you don’t want to spend a considerable amount of money replacing your anodized aluminum pan again.

Hence, you should be wary of adding it to the dishwasher. Secondly, if you have pressed or cast aluminum pans, they may cause damage to other dishes and utensils in the dishwasher.

So, if you care about your aluminum cookware, then the best choice is to avoid using the dishwasher to clean them.

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