Paddington Bear has had some adventures since he was found on a station platform by Mr and Mrs Brown at the start of his first book 49 years ago.

Much has changed for the duffel coat-wearer from Darkest Peru since he came to London, but one thing has remained a comforting constant for nearly half a century: marmalade sandwiches. Until now, that is. Paddington has forsaken his favourite filling in order to advertise Marmite.

From today, television viewers will witness Paddington spotting an advert for new, squeezy bottles of Marmite (themselves an alarming move away from the traditional glass jars) and deciding to try them. He tucks into a sandwich – loving its unusual, taste, then shares it with a pigeon, who is distinctly unimpressed, reflecting the yeast extract spread’s “love it or hate it” slogan.

The adverts are the first time in 20 years that Michael Bond’s creation will appear as an animation, rather than in cartoon or print forms.

Unilver, the makers of Marmite, which dates from 1902, hope the campaign will play on the nostalgia factor for older viewers while also encouraging younger viewers to give it a try.

Cheryl Calverley, Marmite brand manager, said: “We are really excited to be working with Paddington Bear. Both the Marmite brand and Paddington bear are British institutions and bring back warm nostalgic childhood memories”.

Karen Jankel, managing director of Paddington and Company, the copyright owners, said: “I think fans might be perturbed is they thought he was giving up marmalade, but they should know that he’s not. He just wanted to try something different.”

The books have sold more than 30 million world-wide, and have been translated into 30 languages, but they are just one strand in a mammoth merchandising operation which has seen everything from prints to pyjamas.

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