On a sunny spring day in southern California, a handful of factory workers are scurrying around in heavy black winter parkas. At the Dreyer's ice cream plant in Bakersfield--where they turn out such treats as Drumstick cones, Push-Up pops, ice-cream sandwiches and flavors like double-fudge brownie and rocky road--it's never time to be wearing short sleeves. These days, the temperature is dropping even more. In some of the largest freezers, set at 7 degrees, Dreyer's is producing a new kind of lower-fat ice cream that the company says tastes like the regular artery-clogging good stuff. Plant manager Mark McLenithan opens a chocolate tub and offers a taste. "You can't tell, can you?"

Well, call us skeptical. Light ice cream, with half the fat or at least a third fewer calories, has been around since the 1980s. But most palates haven't been impressed. When you cut down on fat, ice cream tastes more like ice and less like cream. Now Dreyer's, the largest ice-cream maker in the United States with $1.6 billion in sales last year, says it's licked the problem. Its new line of light ice cream is prepared in freezers with lower temperatures and at higher pressure--Dreyer's won't explain the process any further, citing trade secrets--so fat molecules are broken up, flattened out and given a larger surface area. The result, the company says, is a creamier texture. "We can make an ice cream with 5 grams of fat taste as rich as ice cream with 14 or 15 grams," says T. Gary Rogers, the company's CEO, who purchased Dreyer's in 1977.

By limiting more-costly ingredients like milk and cream, Dreyer's can still keep prices steady (a 1.75-quart carton sells for about $5.50), even if the process takes longer and requires freezers twice as large. Dreyer's challenge is to figure out the best way to market this line that it launched last year. How do you entice picky taste buds that have already rejected light ice cream? The solution, Dreyer's hopes, comes in a name change. When the product was first unveiled, it was called Grand Light. But that sounded too much like a meal offered by Jenny Craig. Packages on grocer's aisles now come with a snazzier moniker, Slow Churned--a brand that plays off the fact that the new ice cream is mixed at a slower speed than its higher-fat counterpart. "It evokes a natural, homey recipe rather than a diet food," says Nell Newton, an analyst covering the ice-cream industry.

There are other marketing pushes as well. Dreyer's (which is known as Edy's on the East Coast, so it's not to be confused with its competitor Breyers), is holding an essay contest to give away 1,500 ice-cream parties to neighbors who want to try Slow Churned together. Investments like this, combined with a new ad campaign and R&D, have cost Dreyer's more than $100 million--but they're betting on big returns. The company hopes sales of Slow Churned will rival its regular ice-cream flavors by 2007. Says Rogers: "Over time, as consumers understand full-fat ice cream doesn't taste any better, why would they continue to buy it?" (But not all consumers are equally fooled; taste tests conducted by Dreyer's found that two out of 10 people noticed a difference.) And Dreyer's is banking that it can introduce the same Slow Churned process into its other lines. In March, Hagen-Dazs (which is made in the United States by Dreyer's) unveiled its first light ice cream in rich-sounding flavors like cherry fudge truffle.

At stake for Dreyer's is a larger portion of the $20 billion U.S. ice-cream industry. Sales are hard to boost--the business tends to be stagnant and seasonal. And apart from kooky flavor names (thank you, Ben & Jerry's), creativity is hardly prized. Dreyer's other new product this year, Dibs, is essentially just a smaller version of the chocolate-covered bonbon. Back at the Bakersfield plant, McLenithan can't stop raving about Slow Churned. He predicts it will be the company's "version of Bud Light." That's an ambitious goal but a good one, since it proves that a "lighter" version of an old product need not cannibalize it. It also shows that even if Dreyer's diet ice cream doesn't taste exactly like the original, it might be close enough for people to ask for a second scoop. That would be sweet success.