Light-proof bottles claimed as a world first by Fonterra have been used by dairy companies overseas for more than a decade.
But Fonterra has defended the claim, saying the packaging is used overseas for UHT or flavoured milk, rather than fresh milk and cream.
A 2002 report by US industry journal Dairy Foods detailed the milk producers already using light-blocking packaging.
They included the "LightBlock Bottle" developed in 1997 by HP Hood in Massachusetts, and another, described as a three-layer bottle with a black carbon layer, made by Morningstar Foods for Hershey's milk.
The new Anchor bottle also has three layers, the middle one coloured black.
Fonterra group marketing manager Craig Irwin said triple-layer bottles were already in use for flavoured or UHT milk, but not for fresh white milk and cream.
Mr Irwin said the Anchor bottle applied the multi-layer technology to larger and more complex milk bottles.
"UHT and flavoured milk containers tend to be round in shape and therefore quite easy to manufacture."
Fresh milk was also being packaged in opaque bottles overseas, but Mr Irwin said these used pigmented plastic and were not 100 per cent light-proof.
"We've been clear from our launch that we believe the Anchor bottle is a world first in fresh white milk."
Fonterra's triple-layer bottles have also drawn criticism from recycling companies which described them as a "lower quality" product, and the bottles have been nominated 17 times for this year's Unpackit Worst Packaging Award.
However a packaging authority has defended the new bottle.
Packaging Council of New Zealand acting chief executive Sharon Humphreys said anything that enhanced the shelf life of a product meant less of the product was wasted.
"The product waste is far more environmentally damaging than the packaging," she said.
The bottles were "100 per cent recyclable", she said, just like the previous see-through bottles.
Marketing Association chief executive Sue McCarty said the response to the changed packaging was "testament to how strong the brand is".
Reader responses to the light-proof bottle:
Clive: Don't you love it when marketing people come up with a solution to a non-existent problem.
Liddy: Now have milk that takes much longer to get cold (has anyone else noticed that?), we can't see how much is left and the bottle is not as easily recyclable.
Heather: Unless your fridge is faulty, the light goes off when you shut the door so why waste the money on a fancy bottle?
Read more: Do you like Anchor's new milk bottles?