Updated

For years there have been warnings about how unhealthy fast food is for consumers.

Now in an attempt to put a fresh and healthy face on the french fry, the world's No. 2 hamburger chain is launching a new crinkle-cut french fry on Tuesday that it says has about 20 percent fewer calories than its regular french fries.

Burger King says a small order of the new "Satisfries" clocks in at 270 calories because of a new batter that doesn't absorb as much oil. By comparison, a small order of its regular fries, sans crinkles, has 340 calories.

The concept of taking an indulgent food and removing some of the guilt isn't new, of course. Supermarkets are filled with baked Lay's potato chips, 100-calorie packs of Oreos and other less fattening versions of popular treats. Such creations play on people's inability to give up their food vices, even as they struggle to eat better. The idea is to create something that skimps on calories, but not on taste.

Burger King executives say people won't be able to tell that Satisfries are lower in calories. It says they use exactly the same ingredients as its regular fries — potatoes, oil and batter. To keep kitchen operations simple, they're even made in the same fryers and cooked for the same amount of time as regular fries.

The difference, Burger King says, is that it adjusts the proportions of different ingredients for the batter to block out more oil. The company declined to be more specific. Another difference, the crinkle-cut shape, is in part so workers will be able to easily distinguish them from the regular fries when they're deep frying them together.

"You need to make things as simple as possible," says Eric Hirschhorn, Burger King's chief marketing officer.

As per capita consumption of french fries has declined over the years, frozen potato suppliers have been working on ways to reduce fat and calories in french fries, said Maureen Storey, president and CEO of the Alliance for Potato Research & Education, an industry group.

"It's actually not an easy thing to do to because consumers want the same taste and the same texture," she said.

Alex Macedo, head of North American operations at Burger King, said the chain worked with one of its potato suppliers, McCain Foods, to develop the lower-calorie fries. He said McCain can't sell the fries to other fast-food clients and that different suppliers might have a tough time imitating them.

Burger King took great pains keep the launch of Satisfries under wraps. Last week, reporters were invited to preview a "top secret new product" at a New York City hotel, where they were asked to sign non-disclosure agreements. Attendees were each served a carton of the fries on a plate that looked and tasted like any other fries, even leaving the familiar grease stains in their paper cartons.

Burger King led off its presentation by comparing the fries to the "leading french fries," which are made by rival McDonald's. On a pound-for-pound basis, executives noted that the new fries have 30 percent fewer calories than those served at the Golden Arches.

The comparison to McDonald's may prove to be confusing for some, since fast-food chains each have their own definitions of what qualifies as a small, medium or large.

A small serving at McDonald's, for example, weighs considerably less than a small order at Burger King. As a result, a small order of McDonald's fries has 230 calories — which is still less than the 270 calories for a small serving of Burger King's Satisfries. A "value" order of Satisfries at Burger King — which is closer in weight to the small size at McDonald's — has 190 calories.

Satisfries is the latest gambit by Burger King Worldwide Inc. to revive its image after a series of ownership changes in recent years. 3G Capital, the Brazilian private investment firm that bought the chain and took it private in 2010, kicked off a campaign last spring with a revamped menu and star-studded ad campaign.

The splashy moves came just before 3G announced a deal to take Burger King public again. The deal was structured in a way that let 3G more than recoup the $3.26 billion it paid for the chain, while still maintaining a majority stake. Burger King's stock price is up 37 percent over the past year and trading close to $20 per share.

The company has continued to press ahead with new menu items in hopes of pushing up soft sales, but the efforts haven't yet yielded results. For its second quarter, sales at restaurants open at least a year slipped 0.5 percent in the U.S. and Canada, where it has about 7,200 locations. The metric is a key gauge of health because it strips out the volatility of newly opened and closed locations.

Still, Burger King is betting Satisfries will be so popular that people will even be willing fork over more money for them. The suggested price for a small order of Satisfries is $1.89, compared with $1.59 for regular fries. That's a 19 percent markup.

Based on reporting by The Associated Press.

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