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What items should you not put in the dishwasher to avoid regret?

07/08/2026

Although household dishwashers are considered a “savior” for women, helping them reduce the burden of housework. However, not all items can be washed in a dishwasher. If you do not understand and are not clear about this, it can easily lead to damage to the items, which can also be the cause of the dishwasher malfunctioning. Let’s explore with Kocher which items should not be used in the dishwasher.

What items should you avoid putting in the dishwasher to prevent regret?

Table of Contents

1: Lacquered items

Lacquered items have poor heat resistance, and the lacquer can easily chip off when exposed to high temperatures or sudden temperature changes. Therefore, washing lacquered items in the dishwasher can cause them to be damaged due to the temperature and water pressure.

2: Copper and gold-plated items

Items made from these materials are very prone to oxidation, tarnishing, and fading when exposed to high temperatures and detergents in the dishwasher. Therefore, if you wash them in the dishwasher, the sparkling beauty of those items will definitely no longer be beautiful.

3: Aluminum items

Aluminum items can technically still be used in the dishwasher. However, after a long period of use, aluminum is very likely to tarnish and lose its original shine. So, you should also be cautious when placing them in the dishwasher.

4: Premium glassware

Premium glass items are very thin and fragile due to the strong impact of water force and temperature. Moreover, the detergents in the machine can cause them to become cloudy after a long period of use.

5: Thin plastic or synthetic fiber items

Because the water temperature in the dishwasher can be quite high, sometimes reaching 70°C, placing these items inside can easily cause deformation or produce harmful substances that affect health. Even harder items like plastic cutting boards or premium plastic bowls should not be placed inside as they will still tarnish.

6: Wooden items

Wooden items such as cutting boards, spoons, and wooden-handled knives should not be placed in the dishwasher because over time, the detergents used in the machine will wear down and scratch the wood. Furthermore, the heat during the drying cycle may cause the wood to warp or crack. Therefore, wooden items should be cleaned by hand to ensure long-term use.

7: Non-stick coated utensils

For utensils with a non-stick coating such as pots and pans, you should not put them in the dishwasher. This is because, to clean them, the dishwasher must operate at high temperatures, with strong water jets under high pressure and high concentrations of detergent, which can cause the non-stick coating to peel off, affecting health after prolonged use. For these utensils, it is best to clean them by hand to ensure safety and longevity.

8: Knives and scissors

Detergents can corrode the blades of knives and scissors, making them no longer sharp as they were initially. Moreover, hot water and high drying temperatures can loosen the handles of knives and scissors over time.

9: Bottles, jars, and containers with small openings

Items such as bottles, jars, and glass containers with small openings may not be completely cleaned by the dishwasher. This is because the water jets may not reach inside the containers.

10: Thermos bottles or cups

The temperature in the dishwasher is quite high, so washing thermos bottles or cups can reduce the insulating properties inside them. If you want to wash them, it is best to place them on the top rack, away from the heating element of the machine to ensure safety.

For high-end dishwashers, being equipped with special features and advanced modern technology will help protect items in the best way possible. Therefore, you can completely rest assured to clean all types of plates, bowls, and cups without worrying that they will crack or be damaged during the machine’s operation. In addition to this comprehensive cleaning solution, optimizing efficiency and coherence for the cooking space with smart European-standard devices is also something many families aim for. In the kitchen appliance sector, Köcher proudly leads in Vietnam by bringing German technology into induction cookers, creating a safe, economical, and modern cooking space for every family.

Thank you for taking the time to read this article. I hope the information and technological solutions I share will be helpful to you in building and using a convenient kitchen.