A Matter of Taste

Chinese noodles should glide through the lips with a satisfying slurp. Orange juice should taste sweet at first, then slightly tart. A swallow of beer should carry a tiny nip of bitter, not a puckering bite.

A matter of opinion, you say? The experts at Oregon State University's Sensory Science Laboratory might reply "Yes, it is; consumer opinion." For more than 40 years, researchers at the Sensory Science Lab in OSU's Department of Food Sciences and Technology have devised ways to translate matters of individual taste into usable, measurable data.

In a booth at OSU's Sensory Science Lab, a member of an evaluation panel checks out a coffee sample. Photo: Bob Rost

Sensory Science Lab research projects recently have identified the most desirable characteristics for orange juice, green beans, hand lotion, after-dinner teas and fruit-flavored rum. They all have given manufacturers valuable data to answer that age-old question: What does the public want?

"If a company is going to create a winner, it has to have a product idea that satisfies (consumers') wants and needs and meets their taste expectations, said OSU food science and technology professor David Lundahl.

As well as identifying what consumers prefer, OSU's sensory lab helps manufacturers refine their products. Mina McDaniel, who has headed the Sensory Science Lab since 1983, said an upcoming research project may help food processors solve a long-time dilemma: How to neutralize the sour taste of acids added as preservatives in products such as salad dressings.

"We are planning to see which sweeteners and salts work best on which acids," McDaniel said. "And then we'll go the manufacturers to propose additional research."

Experience has taught McDaniel that food manufacturers are eager to back projects aimed at solving production problems. That has been the case since McDaniel started working in the food sciences industry in 1968. "Sensory testing was wide open then," she said.

In OSU's sensory lab, a volunteer rates samples by answering questions on a computer screen. Other food tasters prefer to offer their opinions the old-fashioned way, on a printed form. Photo: Bob Rost

Thirty years later, the demand for sensory professionals far outstrips the number of students graduating each year with a sensory specialty. Lundahl said at least eight universities in the nation offer a sensory science lab where companies large and small can present research questions. They include the University of California at Davis, the University of Nebraska, Kansas State University and a large program at Cornell University in New York. "OSU definitely is a pioneer in the field, and has one of the largest graduate programs," he said. Program graduates often are recruited by industry while still students. They usually have their pick of jobs afterwards.

Lue-Lih Yeh, a native of Taiwan and a 1998 graduate of the Sensory Sciences program, had offers from overseas companies but wanted to remain in the United States. Yeh recently accepted a position with a New Jersey-based food company whose representatives were impressed with her work developing a new scale for measuring food preferences of both Western and Asian consumers.

During international taste tests at OSU involving more than 200 Korean, Chinese, Taiwanese, Japanese and American students, Yeh and Lundahl proved what already had been suspected: Asian students, whose culture stresses polite behavior, are often reluctant to select the "extremely dislike" or "dislike very much" options at the negative edge of the standard nine-point hedonic scale. Commonly used in Western cultures, the hedonic scale records reactions from extreme aversion to strong appeal.

Mina McDaniel, left, head of OSU's Sensory Science Lab, and food science professor Dave Lundahl with examples of products tested at the facility, which has operated for more than 40 years. In the food science industry, the demand for sensory professionals outstrips the number of graduates, says McDaniel. OSU has been a pioneer in the sensory field, says Lundahl. Only about eight universities have labs where companies can test food products. Photo: Bob Rost

Yeh tested the students' reaction to 17 Asian and American snack foods. She demonstrated that although Asian students may loathe cheddar cheese and tart raspberry-flavored snacks, they avoided giving these flavors strongly negative responses.

By contrast, American students and Asian students who had lived in the United States for a while had no trouble expressing extreme dislikes for some snack choices. For example, when asked their reaction to seaweed chips, cuttlefish peanut balls or spicy chicken feet, many Americans readily marked the "strongly dislike" option.

"Some (Americans) refused to even sample the chicken feet," Yeh said. Yeh's research did more than prove what had been suspected, however. She developed a new cross-cultural scale that used numbers to indicate degrees of preference and generated a genuine response, regardless of the tester's nationality.

Volunteer testers are key to the success of OSU's sensory science lab. Some are recruited just to give their off-the-cuff reaction to products, as with Yeh's research. Others, such as OSU food sciences major Dawn Bittner, go through training to teach them how to detect the subtle tastes and smells of the particular product being tested. Bittner is a trained volunteer taster participating in Judy Briggs' thesis technology. Briggs' research is far from strictly academic, however: It is sponsored by a large coffee manufacturer.

The company-which wishes to remain anonymous-has commissioned OSU's sensory lab to rate how storage conditions of roast, ground and packaged coffee ultimately affect the coffee's taste in the cup.

Husin Husurianto, an undergraduate in OSU's Department of Food Science and Technology, prepares coffee samples for sensory evaluation. Food samples are coded so only researchers can identify them. Photo: Bob Rost

For her research, Briggs first trained Bittner and the other volunteers to recognize and rate the nuances of coffee's flavor, aroma, "mouth feel" and aftertaste. The tasters identified coffee qualities ranging from a chocolate undertone to "doused campfire" or "burnt cigarette."

The volunteer tasters neither see nor speak to each other during testing sessions, but their training has made their responses remarkably consistent. Of course, some individual differences arise. "Some people have a tough time detecting bitter," Briggs said. "It's just a genetic thing."

Bittner said the volunteers take the research project rules very seriously, even though they work almost for free. They are compensated in coupons, a little money, pastries and the satisfaction of helping someone complete their research. Bittner, an undergraduate who plans to pursue a career in either wine-making or microbrewing, said she has learned a great deal from being a tester, including how to recognize subtle qualities of some Oregon wines and Brazilian rum that were tested at the lab.

However, such testing is for science, not for fun. Any samples are diluted to 20 percent alcohol because it is difficult to detect flavors at higher alcohol percentage levels. Once the tasters sniff, sip and swirl the samples, they spit them out. "You are encouraged to expectorate so that you don't dull your sensory responses," Bittner said. The sampling method also ensures that nobody leaves the lab with a buzz.

Refresher training: The smells of these items—chocolate, fruity, papery, etc.—represent standard characteristics of coffee, explains OSU food science graduate student Judy Briggs. Taste panelists smell them just before they evaluate coffee samples as a reminder of what to look for. Photo: Bob Rost

The companies that commission this sort of research use the findings in a variety of ways. For example, although the coffee project sponsor will remain anonymous, the results of the research will be available once Brigg's thesis is published, McDaniel said.

Beer manufacturing giant Anheuser-Busch encourages publication of some of its research findings into the sensory properties of hops.

A project testing for the most desirable properties of Asian noodles has better positioned Oregon wheat farmers to complete for their share of the Asian wheat market. Mark Kruk, laboratory manager for the Oregon Wheat Marketing Center, said the sensory lab, funded by a grant from the U.S. Department of Agriculture, conducted testing to find out what flavors, textures, colors and "mouth feel" Asian consumers prized in their wheat noodles.

McDaniel, who directed the three-year project, said wheat growers learned that most consumers like a creamy-white, non-gummy noodle that slithers smoothly as it is eaten from a bowl and has a pleasing "al dente" bite. Such information is important to Oregon wheat farmers competing with Australia and Canada for a share of the multi-billion-dollar Asian noodle manufacturing market. It is such testing that illustrates the value of measuring specific matters of taste.

Food tasters' training: Volunteers learn sensory evaluation "concepts" before serving on a tasting panel. They are, left to right: Patty Boonprason, Christina Edwards Van Muijen, Anton Selivanchick and Titia Thorp. Some assignments at OSU's Sensory Science Lab are yummy, researchers point out. But others, such as participating in studies of the shelf life of frozen foods, may be less appetizing. Photo: Bob Rost

With up to 25 varieties of Oregon wheat to choose from, growers can tailor their planting decisions to their chosen market.

"The bottom line for the grower is whether that variety will consistently perform well," Kruk said. "OSU filled a void (by determining) what it is about a noodle that is acceptable or unacceptable."