Completely banishing trans fats will be a challenge for Minnesota's food companies, but like much of the industry they've made significant progress over the past decade.

General Mills, Hormel and other firms hit the labs hard as science groups and regulators — notably the Food and Drug Administration — have made clear their disdain for trans fats.

The companies have made considerable progress. A General Mills spokeswoman said more than 90 percent of the Golden Valley company's retail products are now labeled as zero grams trans fat.

But spokeswoman Kirstie Foster said in an e-mail that Thursday's announcement by the FDA that it wants all trans fats out is a major development that companies will need to "quickly consider and respond to."

Trans fats still show up in some of General Mills' Betty Crocker cake mixes and frostings, as well as in its venerable Bisquick brand. One line of Pillsbury refrigerated biscuit dough has trans fats, as does the company's Gardetto's original snack mix.

Austin-based Hormel Foods said its branded, retail food portfolio is 97 percent free of trans fats. However, Hormel's Mary Kitchen corned beef hash contains some, as do a few iterations of its Simple Ideas line of refrigerated meat entrees.

Marshall-based Schwan Food Co., maker of ice cream and Red Baron, Tony's and Freschetta's pizza, says 96 percent of its offerings have no trans fats. None of its products sold to schools — Schwan's is a major school vendor — have trans fats, said Karen Wilder, the company's director of scientific and regulatory affairs

Removing trans fats "has not been an easy proposition," Wilder said. "It's been a technological challenge."

The FDA in 2003 issued a regulation that by 2006, food manufacturers had to list trans fat content on the "Nutrition Facts" panel on almost every retail food label.

During 2006, New York became the first U.S. city to ban trans fats in cooking oils used in restaurants.

Fast-food behemoth McDonald's got religion early, announcing in 2007 it would switch to trans fat-free oils in its French fries. Minnetonka-based agribusiness giant Cargill, a big processor of canola, soybean and palm oil, played a key role in developing McDonald's reborn fries.

"For a decade or so, we have been working with food manufacturers to reduce trans fats," said Mark Klein, a Cargill spokesman. "The number of customers that buy them has dwindled."

Mike Hughlett • 612-673-7003