COLUMBIA, Mo. -- Here's a mouthful about how we savor ice cream flavors, courtesy of Seo-Jing Chung, a doctoral candidate at the University of Missouri:
"When you masticate food, essentially, flavor volatiles come out from the food matrix to the head space and it moves over to your nasal cavity."
Translation from 12-year-old Sterling Wyatt, licking a scoop of chocolate ice cream on a 96-degree day: "Heavy. Rich. Yummy. Mmmmmmmm!"
July is National Ice Cream Month, celebrating one of summer's simple pleasures.
But the way ice cream flavors are achieved is anything but simple.
A tiny adjustment in fat content or tweaking one of dozens of chemicals in flavor components can thrill or turn off an ice cream devotee.
At the University of Missouri-Columbia, Chung, 27, and other researchers are trying to create a low-fat strawberry ice cream that tastes as satisfying as the full-fat version.
It's an elusive goal. But there is enough interest in finding answers that the U.S. Department of Agriculture has provided a $108,000 grant to finance two years of study on the subject at Missouri, which through its dairy operations has a rich tradition in ice cream research.
That tradition reached a new level with the creation in 1987 of an endowment by ice cream researcher Wendell Arbuckle within Missouri's Department of Food Science and Nutrition.
In 1989, the school opened its own campus retail outlet nicknamed for Arbuckle, Buck's Ice Cream Place. All of the ice cream sold at Buck's is manufactured fresh on campus in a well-equipped kitchen that can crank out 30 gallons per hour.
"It's a classroom, it's a laboratory, it's a commercial ice cream plant," said Buck's manager, Rick Linhardt.
The house specialty is Tiger Stripe, a French vanilla tribute to the school's mascot, its pale gold color adorned with stripes of dark chocolate fudge. A five-ounce scoop of Tiger Stripe contains nearly 7 grams of fat and 200 calories.
While Buck's hosts ice cream fans on hot summer days, upstairs in the school's research labs the recipes are manipulated over and over, in search of that elusive quality in low-fat ice cream - the flavor of full fat.
"Fat is the flavor carrier in ice cream, and it's hard to improve on that flavor," said Ingolf Gruen, a professor specializing in flavorings who oversees ice cream research at Missouri.
The challenge is evident in ice cream sales statistics. Sales of zero-fat ice cream were down 23 percent in 2000, the latest numbers available from the International Dairy Foods Association. Low-fat and reduced-fat ice cream sales declined 8 percent for the same period, while sales for full-fat ice cream were up more than 7 percent.
"Consumers are really picky when it comes to a national icon like ice cream, and they just enjoy the full, richer flavor that the fat ice creams have. They look at ice cream as sort of an indulgence and they get that with the higher fat levels," said David Landau, spokesman for the Washington-based trade association.
That cultural preference for full-fat taste motivates researchers like Chung, who has spent about two years dishing samples of ice cream into a glass device that imitates the workings of a human mouth.
She introduces an enzyme that mimics human saliva, while a magnet moves around a 2-inch sliver of Teflon-coated metal, imitating movements of the tongue.
The flavors of each sample - the "volatiles" to which Chung refers - are forced out of the ice cream into the artificial mouth by infusions of nitrogen gas.
These microscopic bits of flavor rise until reaching an absorbent strip, which is removed for computer analysis.
That analysis, one of dozens Chung will examine each day, finally appears on a yellow computer screen as green peaks and valleys, each jagged point representing a bit of flavor.
"Ice cream is a very complicated matrix," Chung said.
"Of course, the human element in ice cream sampling can never be eliminated," Gruen added with a shrug.
Of course, how could a mechanical device account for the lusciousness of full-fat ice cream?
Humans must be part of the research, bringing their prejudices and preferences. Gruen said the mechanical mouth helps refine the samples subject to human taste-tasting.
At the school, human ice cream testers line up in small cubicles. Samples of ice cream are pushed through windows. Sometimes colored lights illuminate the samples. Other times, test subjects wear breathing devices that propel flavor volatiles through their noses into research receptacles.
All this to get to the result Sterling Wyatt articulated thusly during his visit to Buck's: "Mmmmmmmmmm."
His mother, registered nurse Sherry Wyatt, licked at her scoop of butter pecan and said she would appreciate a lower-calorie version. But it's a matter of taste, "and the low-fat ice creams just don't have it."
"I'll be waiting on the research," she said, "because everybody likes ice cream, and everybody wants to be thin. Now how do we do that?"
On the Net:
Buck's Ice Cream: http://www.fse.missouri.edu/bucks/index.html
MU Food Science Program: http://www.fse.missouri.edu/foodscience/
|Ice cream at a glance:|
Total U.S. production in 2000: 1.6 billion gallons, or about 23 quarts per person.
Total U.S. sales in 2000: Nearly $20 billion.
U.S. households consuming ice cream: More than 90 percent.
Full-fat ice cream's share of the market: 80 percent.
Top five ice cream flavors based on 2001 U.S. supermarket sales: Vanilla (28 percent), chocolate (8 percent), Neapolitan (7 percent), butter pecan (4.5 percent) and chocolate chip (3.5 percent).
Source: International Dairy Foods Association and U.S. Department of Agriculture.