Question 1

What should never go in a dishwasher?

Accepted Answer

Dishwashers combine high temperature, prolonged wetting, and strongly **alkaline** detergent. Each damages particular materials, and the alkalinity is the part people underestimate.

**Cast iron and carbon steel.** Detergent strips the polymerised oil **seasoning** and the prolonged wet cycle causes rust almost immediately. Wash by hand and dry on the hob.

**Good knives.** Two problems: the alkaline detergent and heat can damage the edge and cause corrosion, particularly on high-carbon steels, and knives knock against other items, dulling and chipping. Handles of wood or composite also degrade.

**Wood.** Boards, spoons and handles absorb water, then swell, crack and split as they dry. The heat also breaks down glues in laminated boards.

**Aluminium** that is not anodised. Alkaline detergent reacts with aluminium, causing **oxidation** that leaves a dull grey or black finish. This is irreversible. Old aluminium pans, some baking trays and moka pots are affected.

**Copper and brass**, which discolour and lose their finish.

**Non-stick cookware.** Many manufacturers now say dishwasher safe, but detergent and heat shorten coating life regardless. Hand washing genuinely extends it.

**Insulated flasks and travel mugs**, unless explicitly rated. Water enters the vacuum seal and the insulation is permanently ruined.

**Hand-painted, gilded or antique china.** Decoration applied over the glaze is abraded off, and gold trim degrades.

**Crystal and delicate glassware**, which can etch — a permanent cloudiness caused by soft water and alkaline detergent leaching minerals from the glass.

**Anything with a sticker or label**, which comes off and blocks the filter.

**Melamine, and thin plastics** not rated dishwasher safe, particularly on the bottom rack near the element.

**"Dishwasher safe" means it will not be immediately destroyed** — not that repeated cycles are harmless. Top rack placement reduces heat exposure.

Question 2

How do I care for a cast iron pan?

Accepted Answer

Cast iron is more forgiving than its reputation suggests, and most of the strict rules people repeat are unnecessary. What actually matters is keeping it dry and maintaining the seasoning. Seasoning

Question 3

Why does my non-stick pan stop being non-stick?

Accepted Answer

Because the coating is a thin polymer layer bonded to metal, and everyday kitchen use degrades it in several ways at once. A non-stick pan is a consumable, not a permanent item, and understanding

Question 4

What do dishwasher salt and rinse aid actually do?

Accepted Answer

Two completely different jobs, and neither is a cleaning agent — which is why leaving them out produces specific, recognisable faults rather than simply dirtier dishes. Dishwasher salt. Not for

Question 5

How does a dishwasher actually clean without scrubbing?

Accepted Answer

Through a combination of high-pressure water, heat, and chemistry that is considerably more aggressive than washing-up liquid — and the chemistry does most of the work people attribute to scrubbing.

Question 6

Why does my dishwasher leave a white film on glasses?

Accepted Answer

There are two quite different causes with the same appearance, and distinguishing them matters because one is removable and the other is permanent. Mineral deposit from hard water is the common one.

Question 7

How can I remove stubborn stains from my dishwasher?

Accepted Answer

To remove stubborn stains from a dishwasher, use vinegar, baking soda, or citric acid. Regular maintenance and cleaning can prevent future stains.

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