A snack bar for his daughter's lunchbox turned out to contain more protein than Brent Charles was expecting.
As he popped the Mother Earth snack into the box, 8-year-old Brooke spotted a moth larva and its silky web inside the wrapper.
"There was a very nice live maggot in there," Mr Charles, of Paraparaumu, said. "It was very much alive and by no means small.
"Its name implies it's all very healthy, but it's not the sort of protein I wanted to come across. If I wanted a protein bar, I would have bought one."
He complained to manufacturer Prolife Foods after buying the pack of eight apple and raspberry fruit sticks at Pak'n Save in Paraparaumu last week.
Prolife had the bar analysed and responded by "pointing the finger" at Pak'n Save owner Foodstuffs, he said. But he believes the manufacturer is passing the buck, and "opting themselves out of the problem".
He was told the factory was treated weekly for pests such as moths and larvae, and had monitoring and killing stations to detect, attract and kill any flying insects.
But it had no control over the storage of products in Foodstuffs' warehouses, and an unusually warm summer would cause more infestation than normal.
Prolife said that, if the product was the problem, it would have expected more complaints.
However, Mr Charles said he believed the contamination must have come before packaging, since the creature was inside an airtight packet.
"I'm really not happy with the way it's been handled. It's just been dismissed," he said of his complaint.
"Somewhere along the line, people need to stand up and take notice if things aren't right."
Prolife chief executive Andrew Smith said the common pantry moth larva was not dangerous, but it was hard to know when infestation began, since the larvae were microscopic when they began life, and could burrow into packets.
He said he had not intended to blame Foodstuffs, but "we know it wasn't in the bar when we produced it".
The matter was taken seriously, and Mr Charles had been given apologies and a gift basket.
"It's very rare, but there are lots of these moths out there at this time of year all through the supply chain.
"I'm really disappointed that the consumer saw something unpleasant."
A Foodstuffs spokeswoman confirmed the Pak'n Save store had "facilitated the communication between the customer and the supplier and made every effort to ensure his concerns were remedied".
She said Foodstuffs had an excellent 20-year relationship with Prolife Foods.
"We do appreciate the customer's concern around Prolife's response, but we have every confidence that Prolife will resolve this issue directly with the customer."
- The Dominion Post