31/10/06 CHICAGO (AP) -- KFC's announcement that it will eliminate trans fats from its cooking oil puts more pressure for alternatives on companies that make and distribute the oil.

So far, no single, all-purpose product has been developed to replace the hydrogenated oil that once seemed the answer for the packaged- and fast-food industries.

Amid the continuing outcry about the evils of trans fats, why has it taken so long to get them out of products?

Oil producers have been experimenting with new versions for years but have been slowed by the complexities involved, according to Robert Reeves, president of the Institute of Shortening and Edible Oils, a trade association representing the refiners of edible fats and oils. He said it takes at least eight years to develop new seed varieties.

But he added: "You'll see more and more of these oils in the future. Given another five years, the conversion will be largely complete."

Numerous alternatives have emerged, including the trans fat-free soybean oil that KFC said Monday it will be using in its U.S. restaurants by April. Palm oil, cottonseed oil, high-oleic canola and sunflower oil and low-linolenic oil all have been developed with the anti-trans fat trend in mind. But not enough are on the market to meet heavy demand.

"It's a rather sophisticated and complex process to remove these fats," Reeves said. "There are structural and functional characteristics that must be maintained in the products you're trying to mimic and substitute for. And there are supply considerations that have to be made."

Most importantly, companies must be sure that consumers will accept the change. In 2002, McDonald's Corp. pledged to switch to a healthier cooking oil for its french fries but delayed the plan indefinitely a few months later, citing product quality and customer satisfaction as priorities.

Hydrogenated oil is a $1.5-billion-a-year business in the United States, so large manufacturers have a lot at stake.

Archer Daniels Midland Co. has been touting its NovaLipid, a no-trans-fat cooking oil it launched in 2003. Cargill Inc. and Bunge Ltd. have cited their focus on developing soybean varieties that yield less trans fat than hydrogenated oils. Archer Daniels Midland and Bunge did not return calls Monday when asked for comment about the KFC announcement.

Cargill spokesman David Feider said the Minnesota-based company has been researching the issue for a decade or more. In addition to searching for new oils, the company has explored eliminating trans fats through alternative processing techniques and reformulating existing oils, Feider said.

"We can't overemphasize how challenging this undertaking is," he said. "Reducing trans fats while maintaining the taste and texture consumers want involves trade-offs for food companies in terms of functionality, taste, texture and cost. There is no drop-in solution."

But the packaged-food industry is pushing hard for replacements as it introduces scores of new products designed to meet accelerated consumer demand. Mintel International Group, a Chicago-based consumer research firm, says there have been 1,021 new products introduced in the U.S. this year featuring low, reduced or no trans fats, compared with 689 for all of last year and 365 in 2004.

Mintel analyst Maria Caranfa, a registered dietitian, called the KFC announcement a step in the right direction.

"It's going to bring out some innovation in the fats and oil companies," she said.