Campaigners have urged the government to stop tobacco companies adding chocolate and other similar ingredients to cigarettes.
There are hundreds of ingredients in cigarettes
It follows reports that British American Tobacco has been carrying out tests on chocolate and alcohol-flavoured cigarettes.
The company says the tests are part of a long-running programme to improve the flavour and casing of cigarettes.
But campaigners say it could encourage children to smoke.
Scientists from BAT have been testing the impact of 482 different ingredients on cigarettes.
These include chocolate, cocoa, wine, sherry, maple syrup and vanilla. Some of these are already use in its cigarettes.
"The tests were carried out at an independent laboratory in Canada," a spokeswoman for BAT told BBC News Online.
"BAT like every other tobacco company uses different substances to enhance the flavour of cigarettes. We are not alone in this and we make no secret of it."
She dismissed suggestions the company was trying to encourage children to smoke.
"BAT does not market to children and we don't want children to smoke."
However, campaigners have criticised the company and have called on ministers to act.
"We would question the whole purpose of these additives," said a spokeswoman for Action on Smoking and Health (ASH).
"Why are they using things that are known to be attractive to children.
"It is possible that some of these things may make smoking even worse for people's health. We don't know."
She added: "We need an independent regulatory authority to oversee this research. It is time for the government to act."
Those views were echoed by the British Medical Association.
"It is disgusting that the tobacco industry is trying to find new ways to
tempt children to start smoking," said a spokeswoman.
"Cigarettes are engineered to be as highly addictive as possible and it is time the government took serious action to tackle this."
The Department of Health said the UK had the strongest cigarette regulations in Europe.
A spokeswoman said that even if tobacco firms added chocolate and other similar ingredients to cigarettes they would not be able to market them as say "chocolate-flavoured cigarettes".
She said a review of the European Directive on the issue could see tighter rules imposed across the European Union.
"We hope the directive will bring everyone up to the same standard," she said.
The Tobacco Manufacturers' Association dismissed claims that adding chocolate and other ingredients to cigarettes would entice children to smoke.
"It is complete nonsense," said Chris Ogden, its director of trade and industry affairs.
He added that manufacturers are only allowed to use ingredients approved by the Department of Health.
"We don't add anything that is not on that list," he said.