First it was Twinings Earl Grey tea, then HP Sauce - and now Flora is at the centre of a potentially costly consumer backlash over reformulation.

In January, Unilever changed the recipe after investing £29m in a new process that it claimed would enhance “the taste and health credentials” of the spread. But the new recipe, rolled out across Flora and Flora Light earlier this year, has hit a bum note with consumers, prompting calls for the original recipe to be reinstated.

On the Flora Hearts Facebook page, user Alex ‘Lexi’ Grover pleaded with Unilever to bring back “real Flora Original”, claiming the “different flavour is ruining all my meals”.

One Mumsnet user, posting as ‘achangeisasgoodasarest’, said they had been using Flora for years and had just bought the new product. “It has a different texture and smells like really cheap cooking margarine. And tastes disgusting,” they wrote. Another user claimed reformulated Flora “tastes funny in mash”, while a further reported that a recently bought tub “had, like, a pocket of liquid in the middle”.

And a user of thegrocer.co.uk complained that it “recreates the unique sliminess” of 1950s cheap marge and alleged it “either uses 25% cheaper oils, or incorporates more water”.

Unilever denied it had switched to cheaper oils. When asked whether the ratio of water to other ingredients had changed, it said: “The new Flora has a new composition, and therefore the ratio of all ingredients has changed.” The new packs state “45% vegetable fat spread”, whereas the old version used to say 59%.

Unilever would not be drawn on whether it was considering reverting to the original recipe, but it insisted tests on the new products had prompted positive feedback. “More of our current users rated the new recipe ‘excellent’ compared with the older recipe,” the company said. “We understand that some people will miss the old Flora, but the consumer research we have done reassures us that the new product is tastier than before.” said.