It is the world's favourite chocolate spread, but a tweak to the Nutella recipe has sent fans a little nuts.
A sharp-eyed German consumer group first noticed the change, revealing that Nutella now contains 8.7 per cent powdered skimmed milk, compared to 7.5 per cent before.
The Hamburg Consumer Protection Centre also pointed out that the sticky spread now has more sugar in it - up from 55.9 per cent to 56.3 per cent.
The watchdog added: "As the colour of the new Nutella is lighter, we are working on the assumption that skimmed milk powder was added at the expense of cacao."
However New Zealand fans need not worry as a the ingredients used to make Nutella in Australia, which is distributed in New Zealand, have not changed.
Ferrero, the Italian company that makes Nutella, confirmed the changes but assured customers that they would notice no difference to the taste and quality of the product.
The firm said that other food companies frequently made similar modifications to their products.
"The quality, the sourcing and all other aspects of Nutella ingredients remain the same," Ferrero said. "The ingredients list is, as usual, displayed on the jar and on the Nutella webpage. All relevant aspects, from a diet perspective, are the same."
But that was of little reassurance to some Nutella aficionados, who expressed their irritation on social media. Some even proposed a boycott of the spread.
"If the rumours of Nutella are true and they are changing their recipe, then I'm done!" one woman wrote on Twitter. Another Twitter user posted a video of a sobbing child and the comment: "OMG no! They are changing the recipe for Nutella."
Another aggrieved consumer wrote: "If the rumours of Nutella changing their recipe are true, I'm boycotting them."
Two years ago, Nutella was at the centre of a row between Italy and France when Segolene Royal, the French ecology minister, blamed the chocolate spread for leading to deforestation in the tropics because it is made with palm oil.
"We have to replant a lot of trees because there is massive deforestation that also leads to global warming. We should stop eating Nutella, for example, because it's made with palm oil," she said in an interview on the French television network Canal+.
Italian politicians leapt to the defence of Nutella, saying many other products were made from palm oil.
Ferrero issued a statement in which it insisted that 100 per cent of its palm oil came from environmentally-certified plantations.