A vegetarian restaurant owner’s decision not to accept the new £5 note because it contains traces of meat byproducts has come under fire from vegetarians and omnivores alike.

Sharon Meijland, who has run the Rainbow cafe in Cambridge for three decades, said she would not allow customers to pay with the polymer note because the animal byproduct tallow is used during the production process.

The businesswoman said she had been shocked and frightened by some of the online reaction to her decision, but that customers had supported her stance.

“Our own customers who are actually in the restaurant in Cambridge have been very favourable, but it is people on Facebook – there’s been a good deal of charming comments such as ‘I hope this comes back to bite you in the ass’,” she said.

On Twitter, Stephen Coltrane said he had eaten at the Rainbow cafe and enjoyed it, but that Meijland’s stance was an “over-reaction”.

Robbie Weir tweeted: “Pretty hypocritical when the food on your menu … contains animal products.”

Denise Venn tweeted: “I’m veggie and I find this so embarrassing. We’re not all this stupid.”

Others accused Meijland, 66, of seeking publicity, but she rejected the claim and said some people were reacting in such a way “because I made a stand”.

Meanwhile, former Smiths frontman Morrissey has hit out at the animal fat contained in the fiver.

The Meat is Murder singer said on his True To You fan site: “If it had been revealed by the Bank of England that the new British five pound note contained slices of cat or dog, the country would be in an uproar.

“But because we have been trained to accept the vicious slaughter of cows, sheep and pigs, the UK media can only make light of the use of tallow in the new British fiver because animal slaughter is thought to be outside of the human grasp and concern.”

He suggested anyone who did not take issue with the revelation that traces of tallow are used in the production process should donate their own bodies for “decorative use in future £5 notes”.

More than 125,000 people have signed a petition calling on the Bank of England to remove tallow from the new notes.

After signing it, Meijland said she spoke with staff and they decided they could not justify handling the notes.

“We all said we all felt very uneasy about handling it. We thought the only way round this is to just not accept them.”

Vowing to stick with the decision, she added: “I am shocked and frightened at my age to get such hatred [online].”

She said the cafe had been runnerup in the best ethical restaurant category in the Observer Food Monthly awards for the last five years.

Polymer bank notes, which last far longer than their paper equivalents, were developed in Australia.

Prof David Solomon, who led a CSIRO team that created the notes, said this week that the tallow controversy was “absolutely stupid”, adding: “There’s trivial amounts of it in there.”

As well as being robust and difficult to forge, Solomon said polymer notes were also more hygienic.

The Bank of England said this week that Innovia, which makes the polymer fiver, was considering “potential solutions” to the problem.

“Innovia is now working intensively with its supply chain and will keep the Bank informed on progress towards potential solutions,” it said.

The £5 note – the first to be printed on polymer by the Bank of England – was introduced in September and is likely to signal the beginning of the end for paper money.