In teaser adverts promoting its "Whopper Virgins" challenge, the fast food chain describes how it sought out farmers in rural Romania, Thai villagers and residents of Greenland's icy tundra to compare its signature burger with arch rival McDonalds'.

"What happens if you take Transylvanian farmers who have never eaten a burger and ask them to compare Whopper versus Big Mac in the world's purest taste test?" one of the adverts asks. "Will they prefer the Whopper? These are the Whopper Virgins."

The "undeniable" results of the chain's "unbiased" global research – which involved "13 planes, two dog sleds and one helicopter" – will be unveiled in a documentary next week, according to whoppervirgins.com, the website promoting the campaign.

"If you want a real opinion about a burger, ask someone who doesn't even have a word for burger," states the site to a haunting theme of drums and pan pipes. "Watch the whopper virgins take their first bite."

"It's outrageous," Sharon Akabas of the Institute of Human Nutrition at Columbia University, told the New York Daily News. "What's next? Are we going to start taking guns out to some of these remote places and ask them which one they like better?"

Marilyn Borchardt, development director for Food First, called the campaign insensitive.

"The ad's not even acknowledging that there's even hunger in any of these places," she told the Daily News.

The campaign has also stirred up a welter of online commentary. Brian Morrissey, writing on Adfreak.com, likens the campaign to colonialism and declares it "embarrassing and emblematic of how ignorant Americans still seem to the rest of the world."

"It doesn't get much more offensive than this," noted The Inquisitor blog. "If visiting poor people in remote locations, some who would be at best surviving on below poverty levels and throwing a burger in their faces isn't bad enough, it gets better, because they also ask the Whopper Virgins to compare the taste of the Whopper to a McDonalds Big Mac as well.

"It's hard to place exactly where this begins on the level of wrongness."