The days of picking little stickers off fruit and veges may soon be over.

Supermarket owner Progressive Enterprises, which operates the Woolworths, Foodtown and Countdown chains, is to test new laser technology to tattoo produce before Christmas.

Progressive's division manager of fresh produce, Stuart Johnston, said this season's stone fruit - due to hit the shelves in about four weeks - would be the first to bear tattoos instead of sticky labels.

Peaches, nectarines and plums would all be part of the trial in 10 central Auckland supermarkets.

"It's for the consumer's benefit: it's non-intrusive, it's not adding anything, it's totally edible," he said.

The technology uses a laser to etch information into the very top layer of the skin of a piece of fruit or a vegetable, visible because of the contrast with a paler layer below.

Its inventor, Canadian Greg Drouillard, said the laser was tuned to ensure it affected only the pigment, even on an undulating surface.

Vegetable dye could be added to the tattoos on lightly pigmented fruit such as lemons.

He said such marking was more convenient for consumers, cheaper for produce packers, and popular with environmentalists because it produced less waste than stickers.

Mr Drouillard, in Auckland this week to help with the trial, said he got the idea for the fruit tattoo when, as a particle physicist at the University of Florida, he accidentally sat in on a produce-packing conference where the talk was how the industry could rid itself of labels.

In the United States, citrus fruit-marketing co-operative Sunkist is among those to have adopted the technology.

The New York Times reported this year that the Government-approved process, called safe by the produce industry, was part of growing efforts to identify and track everything Americans eat - whether for profit or security.

The trial pre-empts a decision on a proposal by Food Standards Australia New Zealand to require country-of-origin labelling on loose produce in New Zealand, including on seafood and pork.

Consumer acceptance of the new process - and whether any aesthetic concerns over tattoos outweigh the inconvenience of stickers - will be the key.

Natural Light Technology, a New Zealand company owned by local produce wholesaler Freshmax, has become the Australasian agent for the technology.

It estimates tattoos could save a packhouse using a two-lane fruit sizer to process 125,000 cartons of apples up to $25,000.

Mr Johnston said Progressive's involvement was not about savings but about "doing the job smarter".

Label technology could ensure stickers on only about 70 per cent of produce, stickers could be swapped and unlabelled fruit priced incorrectly at the checkout.

"It's only a trial at this stage but we see it going mainstream very quickly."