How do you clean whisky glasses?

Yes. Choose the glass programme or a low programme of 50 to 55 degrees, place the glasses apart from each other in the top basket and use the glass holder if the machine has one.

Glass manufacturers work to the standard DIN EN 12875-1: 2005-08 and rate their glasses as dishwasher-safe for up to five hundred wash cycles. The condition is that the glass touches nothing: no other glass, no plate and no metal. Washing glasses together with aluminium items causes corrosion.

Tall stemmed glasses often do not fit in the top rack. They may only go in the bottom rack if the machine has a separate glass programme; otherwise they are washed by hand. If the glass or the leaflet says it is not dishwasher safe, or says nothing, wash it by hand. Rinse off drink residue first, because wine residue damages glass if it stays on for long.

Exactly the dose the manufacturer prescribes, no more. Glass manufacturers and makers of commercial dishwashers all warn against overdosing, of both the washing-up liquid and the rinse aid.

Too little rinse aid leaves drip marks, too much leaves a film. So keep the reservoir filled, but do not set the dosage higher than necessary. The same goes for the salt: the machine needs it to make the softener work, and an empty salt container immediately leads to limescale stains.

If you wash by hand, simply use ordinary washing-up liquid in lukewarm water and then rinse thoroughly with clean water. That rinsing is the whole point. Do not rinse with boiling water. A decanter should never get washing-up liquid: residues are almost impossible to get out again. Fill the decanter with lukewarm water and leave it overnight.

Because you smell a whisky first and then drink it. Any soap or rinse aid left in the glass therefore reaches your nose before the whisky does.

In the hospitality trade this is a well-known problem. Industry guidelines for cleaning glassware state that grease and soap residues give a musty smell that rises above the drink, and that the head on a beer collapses as soon as there are residues in the glass. With a glass of whisky you see no head to warn you; you only smell a glass that is not right and blame the bottle.

That is why a tasting glass is a piece of craftsmanship in itself. In the shop at Brink 2 in Bathmen there are 1,234 bottles of Scotch whisky between 40 and 46 percent, the bottles that usually go neat into such a glass. The narrower the opening of the glass, the more strongly it concentrates the aroma, and so also the aromas that do not belong in it.

From limescale in the tap water and from too much washing-up liquid or rinse aid. Both settle on the glass as it dries and remain visible as drip marks, haze or a white film.

How hard the water is differs per place of residence. Vitens, the water company for Friesland, Overijssel, Flevoland, Gelderland and Utrecht, supplies water between 2.0 and 15.1 degrees German hardness. One millimole per litre equals 5.6 degrees German hardness, and the Drinkwaterbesluit requires more than one millimole per litre. Ask the water company for the hardness at your own postcode and set the machine's softener accordingly, preferably around 3 to 4 degrees. Water that is too soft is not good either: glass manufacturers report that very soft water attacks the glass.

Limescale and residues can be removed with citric acid or ordinary vinegar, then rinse thoroughly. If the glass surface itself is damaged, that white haze is irreparable. That is the difference you want to establish first, before you start polishing.

Dry them with two large microfibre cloths. Water that dries in the glass leaves behind exactly the limescale and detergent residue you wanted to wash out.

Do not use a tea towel: it leaves lint and a fibre smell. Wash the microfibre cloths at 60 degrees with unscented soap, without fabric softener, because fabric softener leaves a greasy film that you then polish into the glass. Microfibre does not go in the tumble dryer either.

Do not leave glasses to dry upside down on a metal rack, as it damages the rim. After the programme, open the dishwasher door so the steam can escape, because steam that lingers promotes glass corrosion, and take the rack out as soon as possible.

Upright and apart from each other, in a cupboard without strong-smelling goods. Glass absorbs odours from its surroundings, and you smell that odour again as soon as you pour whisky.

So do not place the tasting glasses next to spices, coffee, cleaning products or an open jar, and not in a cupboard above the hob. A closed display cabinet or a shelf of their own is better than a full kitchen cupboard.

If a glass has stood for a long time, give it a sniff before you pour. If it smells of the cupboard, rinse it with lukewarm water and dry it with a microfibre cloth. That takes half a minute and saves a whole dram.