The British-English (later also Irish-English) noun Dutching, also dutching, denotes the practice of sending food destined for the British or Irish market for irradiation in a country, typically the Netherlands, where this process is permitted, in order to mask any bacterial contamination before it is put on sale.

The noun Dutching is from:
– the adjective Dutch, meaning relating to, or belonging to, the Netherlands;
– the suffix -ing, used to form nouns denoting an action, a process, a practice.

The earliest occurrences of the noun Dutching, also dutching, that I have found are as follows, in chronological order:

1-: From Shelf-life or death, by Judy Sadgrove, published in The Guardian (London and Manchester, England) of Wednesday 10^th May 1989:

Food irradiation has been banned in Britain since 1967. It is permitted in 36 countries, including the US and France, Belgium, Netherlands, Spain, Italy and Luxemburg. Six other EC nations forbid it but if Britain and another change over, irradiated food will be sold throughout Europe.
[…]
[…] What does irradiation do?
Food is exposed to a source of low energy ionising radiation (Cobalt 60 and Caesium 137). Low doses below 1 Kilo Gray (kGy) inhibit the sprouting of potatoes and onions, delay the ripening of fruit and kill pests in grains and spices. Medium doses (1-10 kGy) reduce yeasts, moulds and bacteria. Higher doses sterilise food.
As the chemical changes and their biological effects are invisible, it is impossible to discern fresh from irradiated food—without a label. A marketable test is essential. […]
[…]
The World Health Organisation has approved irradiation to date, presumably because it kills the pests and microorganisms that spoil food and cause diseases, such as salmonellosis, toxoplasmosis and campylobacteriosis. But the British Medical Association has pointed out that although it reduces the bacteria, it leaves behind the toxins that make people ill.
Fears have been expressed that it could be used fraudulently to camouflage contaminated food. Prawns have been refused by British port authorities and then accepted after clean-up (“Dutching”) in the Netherlands. It is also not clear whether irradiation would prevent listeriosis (dangerous in pregnant women) and there are worries that it might, by killing off competitive yeasts and moulds, encourage the emergence of deadly botulism.

2-: From He’s a one-man crusade against irradiation: Ken’s fight, by Mike Jamieson, published in the Evening Chronicle (Newcastle-upon-Tyne, Tyne and Wear, England) of Tuesday 31^st October 1989:

Britain’s most tenacious fighter against the Government’s disgraceful plans to permit nuclear irradiation of food is Newcastle’s seafood king, Ken Bell MBE and, ironically, winner last week of the Queen’s Award for Industry.
Recently the chairman of Ken Bell International has been taking his fight to the nation in multi-thousand pound advertisements in national and London newspapers.
[…]
His own view is put thus in one advert: “As responsible food processors we want to supply you with wholesome, clean, freshly frozen food.
“We do not want to compete with rejected, stale dirty and dangerous food, deodorised and embalmed using radioactive nuclear waste to reduce the bacteria of putrefaction.”
Ken Bell, Member of the Order of the British Empire, backs that statement with direct experience.
Three years ago I revealed how he had refused several offers of food consignments that had been secretly irradiated in the Netherlands to disguise contamination for illegal importation into Britain.
He said he also rejected an offer of investment in his firm in return for ending his outspoken opposition. He was subsequently warned it might be dangerous to oppose a lobby of such powerful (though minority) interests.
The contaminated food racket continues. Ken tells me he recently turned down another offer of an irradiated salmonella-contaminated consignment. (It’s known as “Dutching.”)

3-: From The law which brings a revolution in food hygiene: Safe-or-not battle over ‘magic ray’ food scare, published in the Sunday Mercury (Birmingham, West Midlands, England) of Sunday 29^th April 1990:

The biggest controversy surrounding the Food Safety Bill is the proposal to allow the sale of irradiated foodstuffs in Britain.
[…]
Critics of irradiation warn that changing the nature of an organism poses a serious food poisoning threat as you may be dealing with new and more virulent strains of bacteria.
Irradiation can also be used to “mask” unfit foodstuffs by reducing the population of bacteria in heavily contaminated foods to more “normal” levels.
This is known in the trade as “Dutching” and could be used on expensive foods like shellfish.

4-: From Irradiation: It’s Never Too Late To Chicken Out, published in The Sunday Tribune (Dublin, County Dublin, Ireland) of Sunday 3^rd June 1990, in which Helen Lucy Burke quoted “a scientist—who asked to be anonymous”:

“Already in the trade there is a term called “Dutching”. Contaminated prawns were sent to Holland for irradiation and then re-imported.”

5-: From a speech that the Labour politician David Clark (born 1939), then Shadow Minister of Agriculture, Fisheries and Food, delivered on Thursday 7^th June 1990 at the House of Commons, during a debate on food irradiation—source: UK Parliament:

Another basic objection to irradiation involves the argument that it can be used to clean up contaminated food. Conservative Members who are in favour of the technology say that that is impossible. Not only can we challenge that argument but we can give chapter and verse of food that was presented as good food when previously it had been condemned as unfit. I do not want to bore the House, but it is important to put it on the record because we are having some difficulty in persuading Conservative Members that it happened. Bad food can be dressed up as good food.
I shall cite an example that has been proven in the courts of law in this country. In 1986 Young’s found that prawns that it had imported did not match its public health standards. It sent the prawns to Gammaster’s * in Holland for a quick fix — they were irradiated — and they were then re-imported. They passed the bacteriological tests and were sold for human consumption. That is a proven case.
There are many other examples that have not yet been proved. Indeed, I informed the Minister’s predecessor of a number of specific cases. I accept that it is difficult to get the cases to stand up in a court of law. However, it is a widespread technique that is known in the trade as “Dutching”. If that sort of abuse happens when irradiation is illegal, I find it hard to believe that it would not continue if irradiation were legal.

* Gammaster International B.V. is a Dutch sterilisation service provider.