8 Things You Should Never Put in the Dishwasher (and Why)
If you’re like many of us, you love the convenience of a dishwasher. It’s a modern marvel that saves time and energy after a long, busy day. But there’s a catch: not everything is dishwasher safe. If you place the wrong items in the machine, you risk ruining your favorite kitchenware, damaging the appliance, and even leaving behind pesky sticky residues.
This isn’t just scaremongering; understanding what scientists and culinary experts say about dishwasher safety can help you protect your investment and ensure your machine runs efficiently for years to come. Let’s shine a light on what not to put in your dishwasher and how to care for these delicate items.
The golden rule: When in doubt, always check the manufacturer’s label. If it says “Hand wash only,” believe it. The intense heat and high-pressure water jets of a dishwasher are much harsher than careful hand washing.
1. Sharp Knives and Wooden Utensils
It may come as a surprise, but placing your sharp kitchen knives in the dishwasher is a big no-no. High water pressure can force knives against other items, quickly dulling their blades. The extreme heat and harsh detergents may also cause wooden handles to crack, warp, or peel away from the blade. Plus, reaching into a dishwasher loaded with sharp knives poses a safety risk.
How to maintain them: Clean knives and wooden utensils by hand using warm, soapy water right after use. Dry them immediately to avoid rusting, especially for carbon steel, and store them safely in a knife holder. Occasionally rubbing wooden handles with food-grade mineral oil will help maintain their finish. Even if labeled “dishwasher safe,” hand washing will keep your knives sharper for longer.
2. Refined Crystal and Fine Porcelain
Your beautiful crystal glass and fine porcelain deserve special treatment. In a dishwasher, high-pressure jets can cause fragile glass to break or shatter. Harsh detergents and extreme heat can permanently damage the surface, making crystal look cloudy instead of dazzling. Delicate gold or silver plating can fade or chip off completely.
How to care for them: Line a plastic container with a towel to prevent slipping, and gently wash these treasures by hand using mild detergent and lukewarm water. Rinse thoroughly, and let them air dry on a rack or pat dry gently with a lint-free cloth. Never stack heavy items on top of delicate pieces.
3. Cast Iron Pans
Cast iron pans are kitchen workhorses that don’t belong in the dishwasher. The harsh detergents and high temperatures strip away the seasoning— the polymerized layer of oil that gives cast iron its natural nonstick properties. Without this protective layer, cast iron is prone to rust.
Care Instructions: Hand wash cast iron with hot water and a stiff brush (soap is rarely needed). Dry it completely on the stovetop over low heat and lightly oil it after each wash to maintain its nonstick coating. Avoid soaking cast iron pans for extended periods to preserve their quality.
4. Non-Stick Pans
It seems logical that non-stick pans, designed for easy cleaning, would be dishwasher safe, but they’re not! The harsh conditions of a dishwasher can damage non-stick coatings like PTFE or Teflon, causing chipping and reducing effectiveness over time. This means you’ll need to replace your pans sooner than expected.
How to care for them: Wash non-stick pans by hand using a soft sponge and mild detergent. Avoid abrasive pads like steel wool. Always let them cool completely before washing to prevent warping. While some newer ceramic-coated pans claim to be dishwasher safe, hand washing always prolongs their lifespan.
5. Anything with Adhesive Labels
We’ve all faced the frustration of trying to scrub a sticky sticker off a plate after a dishwasher cycle. The heat and water cause labels to break down, leaving stubborn residue on both dishes and inside the dishwasher. Worse, this glue can clog your dishwasher’s filter, diminishing its cleaning efficiency.
How to maintain them: Always remove all labels before putting items in the dishwasher. For stubborn labels, soak them in warm, soapy water to loosen adhesive, and carefully use a razor blade to scrape away any remaining residue.
6. Insulated Travel Mugs and Thermoses
Insulated mugs are fantastic for keeping drinks hot or cold, but they can be damaged in the dishwasher. High heat can ruin the vacuum seal between the double walls, making them less effective. Also, plastic lids and rubber seals might warp, leading to leaks, and harsh cleaning agents can leave behind an unpleasant taste.
Care: Hand wash insulated mugs and lids in warm, soapy water. Use a bottle brush for thorough cleaning inside. Always let the bottle dry completely without the lid to prevent mold growth, and follow the manufacturer’s instructions for maintenance.
7. Copperware
Copper pots and pans are stunning kitchen essentials, but they require special care. The heat and detergents of a dishwasher can tarnish the beautiful finish and hasten darkening and staining. Some detergents can even chemically react with copper, leading to corrosion.
Care: Hand wash copperware with mild soap and warm water, and always dry it immediately to prevent water spots. Regular polishing with a copper cleaner or a simple homemade mixture of lemon juice and salt will keep them gleaming.
8. Antique or Valuable Porcelain
If you own old or hand-painted porcelain dinnerware or bowls, it’s best to keep them out of the dishwasher. The sensitive nature of these items means they can be easily damaged by the harsh conditions inside a dishwasher.
Care: Hand wash these pieces meticulously in lukewarm water with a gentle detergent, and avoid stacking them to prevent chips. Dry them carefully with a lint-free cloth to maintain their beauty.
Conclusion
Knowing what to keep out of the dishwasher can save you time, money, and frustration in the long run. By following these guidelines, you’ll not only protect your valuable kitchenware but also ensure your dishwasher remains in its best working condition. Remember, a little extra care can go a long way in preserving your items for many years to come! So, make that commitment to hand wash your delicate items, and enjoy the peace of mind that comes with knowing your kitchen tools are safe.
