K-State researchers find the right words to design better tasting foods for consumers
Thursday, September 8, 2005
MANHATTAN, Kan. - Ten professional tasters dressed in white lab coats are seated around a circular table, each ready to spear dice-size chunks of mystery cheese with a wooden toothpick.
"Think about what words you're going to use to describe Limburger," says Edgar Chambers IV, director of the Kansas State University Sensory Analysis Lab. "It's not a cheese that most people think of in positive terms."
Although the word "stinky" immediately comes to mind - even elicits a few belly laughs - this is serious work. The tasters have been charged with developing a lexicon, a vocabulary of carefully chosen descriptive words designed to help the consumer identify the taste attributes of various types of cheese.
Since 1982, the professional tasters employed by the lab have literally tasted everything from soup to nuts. Whether it's cheese, green tea, ice cream or - eeeuuwww! - dog food, their senses are trained to evaluate the flavor, texture, appearance, odor and aftertaste of food and beverages in a way other lab tests cannot.
"A machine can tell you what a product is - the chemical or physical mechanics," Chambers says. "But it can't tell you what it tastes like or feels like."
As the first, oldest and largest applied sensory research center in the world, the Sensory Analysis Lab's client list reads like a food industry who's who, including giants General Mills, Frito-Lay, Kellogg's, Keebler, Con-Agra and Kraft. The lab has studied portion control for the U.S. Department of Agriculture. It also has sent its tasters to work on assignments in Italy (ice cream), Germany (cheeses), Thailand (fruit, snack foods) and Korea (green tea, soy milk and kimchee).
"The advantage we see at K-State, compared to other schools, is the depth of experience the panel brings," says Petros Levis, a technology manager in the research and development department at General Mills. "It is a program that has been built over many, many years." Flavor profiles
Chambers has a black-and-white photo dating to 1907. It shows a group of blindfolded panelists tasting and smelling eggs. "We have a long history - at least 100 years - of doing sensory analysis on products," he says.
Sensory analysis got its start as a field of study in the 1940s. Soldiers were losing weight after refusing nutritious but tasteless meal rations. Looking for ways to modify the meals, the U.S. government approached the food industry.
"They said, 'Wait a minute! We don't have a clue how to test food. We know if something is good or bad, but what happens when we add salt? Or MSG?'" Chambers says.
A pioneer in the study of sensory analysis, Jean F. Caul, a retired K-State professor and Chambers' mentor, helped to develop the flavor profile. A flavor profile determines the intensity of each ingredient. K-State typically uses a standard 15-point scale, plotting different levels of sensation perceived by most people. The scale links a specific set of words to a chemical reference and intensityso that a "nutty" note in cheddar cheese for one taster is the same intensity of "nutty" to another.
A consumer taste test panel can tell researchers only whether they like or dislike a product, essentially whether something is considered "good" or "bad." A sensory analysis panel is able to dig deeper, identifying positive and negative attributes that affect taste, such as whether an ingredient has been changed in a product, whether a "new" and "improved" product is likely to have consumer acceptance or how long a product can sit on a supermarket shelf before it goes stale.
Although the lab also tests personal care products, paints and textiles, 60 percent of its work comes from food and beverage manufacturers who pay a few thousand dollars to $200,000 per project. Business is going "gangbusters," up more than 25 percent over 2004,according to Chambers.
Levis at General Mills rates Cornell University, the University of California-Davis and K-State as the top three schools providing the food industry with sensory analysis data. He adds that K-State stands out for its ability to quickly switch between the needs of academia and industry.
In the ever-more-competitive battle for market share, a fast turnaround is a plus. "Twenty-five years ago, Cheerios and cornflakes was all that was in the aisles. There is four times the number of cereals today," Levis says.
Back in his office, Chambers pulls a maroon suede box off a bookshelf. It contains 54 vials, each containing a liquid scent. Without revealing the contents, Chambers holds a bottle to my nose. As a scent wafts up, he asks me to describe the smell. The best I can come up with is "citrus-y."
"That's one level," Chambers says. "But we can train you to recognize (the smell as) apricot. Then we can get down to whether it's cooked or uncooked apricots."
Most people can recognize certain smells by memory - even if they can't quite put a name to them. For instance, clove is a difficult scent to identify, but many people who can't name the smell say it reminds them of a Christmas ham. Likewise, many people can't tell the difference between lime and lemon oils, but they may be able to say it smells like floor wax.
The K-State lab employs 30 professional tasters, but they are not the legendary super tasters, that 25 percent of the population who have more taste buds on average and perceive bitter tastes more intensely than the rest of us.
Instead, Chambers starts with a field of average tasters who can describe what they smell. In a four-month training session, he can teach average taste buds to recognize, and eventually accurately name, the individual compounds.
"Food is like musical notes," Chambers says. "Depending on the way you put them together, you know it's an Oreo or someone's goat cheese."
Margo Fick has been lending her highly trained taste buds to science since K-State's lab opened in 1982. "It gets me out of bed and gets me going," says Fick, a retiree who lives in Manhattan. "It's a good part-time job, but you can't make a living at it."
Professional tasters at K-State work from 9 a.m. to noon, five days a week, 45 weeks a year. Because of the part-time hours, the job attracts stay-at-home moms and retirees.
A dozen tasters are trained to replace any who decide to leave the ranks when their three-year stint ends. But turnover is low. A war of words
It doesn't necessarily take a professional taste tester to identify butyric acid in dairy products. The fatty acid is found in rancid butter. A strong whiff of the stuff smells like - I'm not making this up - baby vomit.
"But sometimes you need it in your cheese," says Janine Beucler, a project manager for Spectrum Designs, a New Jersey-based consulting firm that applies sensory techniques to consumer products. "Sometimes it really stands out, but when it's integrated in a matrix of other flavors it can be just what your cheese needs."
Fortunately, butyric acid means nothing to the average consumer. Instead, they might choose a word like "creamy" to describe the buttery notes in goat cheese.
But which creamy? There are at least three meanings for the same word: creamy, as in the flavor of cream; creamy as in smooth like mayonnaise; and creamy, as in it melts smoothly, like ice cream.
"Consumers use the same word to describe three different phenomena," Chambers says. "We're known for developing lexicon. We try very hard not to use those words that are consumer friendly, but are somewhat meaningless to the researcher."
Which often leads the professional tasters to a war of words. For the next three hours they nibble on cheese and quibble over words such as "strong," "dairy sour" and "astringent." At the end of the day, the group must come to a consensus on the five words they choose to describe each sample.
"Being assertive is definitely a perk in this job," says Kat Caster, a homemaker from nearby Fort Riley. Caster has been a professional taster for four years. She answered an ad for the job and discovered she had a knack - and the stomach - for it. Although, as Caster points out, tasters don't have to swallow.
"I've always considered myself a foodie, and I knew I was outspoken," says the former elementary school teacher.
Although Caster's knowledge of cheese might come in quite handy at a cocktail party, most of the lexicon is developed for academic use. Still, there's a trickle-down effect. As soon as the research is published, it is available for use by industry. "It becomes part of the language," Chambers says. "That's the public institution part of us."
From there, anyone - from the small farmer to the giant food conglomerate - can "design" a product to enhance its flavor profile. For instance, the lexicons might be used by Frito-Lay to develop a new snack food, by banana growers to develop new varieties with a flavor profile similar to the ever-popular Cavendish, or by a small artisanal goat cheese producer to enhance a "strong" flavor characteristic.
"Ultimately, the whole goal is to provide better products to consumers," says Chambers.
The over-50 snacker
Students from around the world are coming to the Sensory Analysis Lab at Kansas State University to learn the research skills that will help them develop new products for the world's supermarket shelves.
Last spring, a team of six K-State graduate students majoring in food science and human nutrition developed a snack that addressed the needs of consumers over age 50. Their project - a hollow, high-fiber pretzel rod packaged in a resealable container with two dipping compartments - won first place and a $5,000 scholarship in the international Elaine Skinner Sensory Design competition sponsored by Sensory Spectrum, a New Jersey-based private consulting firm specializing in sensory analysis.
The K-State students on Team "Back to the Future" included Alicia Jenkins, a research assistant in human nutrition and graduate student in food science, from Manhattan; Ellen Hill, a graduate student in food science from Knoxville, Tenn.; Ziad Matta, a graduate student in human nutrition from Lebanon; Martin Talavera, a graduate student in food science from Peru; Jeehyun Lee, a graduate student in human nutrition from South Korea; and Gaewalin Oupadissakoon, a graduate student in human nutrition from Thailand.
The students determined this age group wanted a snack that was nutritious, easy to chew, easy to open and portable enough to eat on the run. The team also chose a "retro" snack, since older consumers tend to be nostalgic for their childhood.
"Their project was awesome," says Julianna Van Visco, a project manager at Spectrum Design and coordinator for the competition. "They used some processes they would be using if they analyzed the data while working for the company. They were very creative in their use of resources."
And that's good news for these future job seekers.
"I think the companies are beginning to see just how important sensory analysis is," Talavera says.
Just how green is green?
Green tea should be, well, green.
A no-brainer, you say?
Maybe, but professional tasters at Kansas State University's Sensory Analysis Lab are finding some green teas aren't all that green. While teas from Japan are the greenest in color, green teas from Korea range between yellow and green. And green teas from China actually tend to be brown.
To develop a lexicon, or a scientific language to describe green teas, the tasters use paint chip references to accurately measure the intensity of color for 137 different samples of tea from countries around the world, including major producers such as Japan, Korea and China, and tiny producers, such as Kenya.
Words to describe green tea include brown, green, asparagus, Brussels sprouts, celery, green beans, green herb-like, parsley, spinach, seaweed, straw-like and tobacco. Each word used to describe a particular quality in a food or drink is matched with a taste reference - a product, flavor or odor with an assigned an intensity rating that allows the results to be reproduced.
Words to eat by
Want to speak the lingo? Here's a sample of words from various food lexicons developed at K-State's Sensory Analysis Lab. Some of the word associations might surprise you. Who knew some types of fish have a corn-like flavor?
- Corn-like: Aromatics typical of canned sweet corn
Reference: Libby's canned whole kernel corn; Intensity (on 10-point scale): 10
- Dairy: Aromatics commonly associated with cow's milk
Reference: 2-percent milk; Intensity: 6
- Metallic aromatic: A mouth feeling associated with an oxidized silver utensil when it is rubbed inside the mouth.
Reference: 0.15 percent solution of ferrous sulfate in water; Intensity: 7
- Cooked milk: The combination of sweet, brown flavor notes and aromatics associated with heated milk
Reference: Dillon's whole milk; Intensity (on 15-point scale) 4.5
- Butyric: Aromatic that is sour and cheesy, reminiscent of baby vomit
References: Butyric acid (in propylene glycol), Kraft 100- percent Romano cheese; Intensity: 6 for aroma; 9 for flavor
- Sauerkraut: Aromatics associated with fermented cabbage
References: Dimethyl disulfide in propylene glycol, Food Club sauerkraut in juice; Intensity, 9.5
Green Tea Lexicon
- Brown: A sharp, caramel, almost burnt aromatic
References: Sethness AP100 Caramel, place 4 drops of caramel color on a cotton ball and place in a medium brandy snifter and cover; Intensity (on a15-point scale): 7
- Green: Sharp, slightly pungent aromatics associate with green plant/vegetable matter, such as asparagus, Brussels sprouts, celery, green beans, parsley, spinach, etc.
Reference: Fresh parsley water, weight 25 grams of fresh parsley, rinse, chop and add 300 milliliters water. Let is sit for 15 minutes. Filter and serve liquid part. Intensity: 9
- Tobacco: The brown, slightly pungent aromatic associated with cured tobacco.
Reference: Camel Filters (Turkish and domestic blend); Intensity 7
- Dairy impression: A general term associated with products made from cow's milk.
Reference: Philadelphia brand cream cheese; Intensity (on a 15-point scale): 7 for flavor
- Dairy sour: The fermented sour aromatic associated with dairy products such as buttermilk or cream cheese
Reference: Philadelphia brand cream cheese; Intensity 4.5 for flavor
- Tongue numbing: A feeling of a decrease of loss of sensation on the tongue
Reference: Pepsi Cola; Intensity: 3
K-State researchers find the right words to design better tasting foods for consumers By Jill Wendholt Silva, The Kansas City Star. Edgar Chambers IV, director of K-State's Sensory Analysis Lab