Much of Carolyn Ross’s work involves training people to quantify their taste. The sensory evaluation panels that she and her graduate students organize assess taste attributes in fruit and other foods and beverages such as sweetness, acidity, bitterness, and astringency. And “mouth feel,” which contributes enormously to the taste experience.
But for these panels to arrive at a consensus of, say, how sweet a given apple is, or how tart, or how much it crunches in relation to other apples, everyone must agree on the intensity of those attributes.
Before the panel members can evaluate a given food, they will train for a number of sessions, tasting slivers of the same apple, for example, then going through an evaluation procedure, assigning each attribute a score on a 15-centimeter scale, over and over. Individuals must often adjust their scores to match the group’s consensus, until finally, they pretty much agree on how tart that fruit is, how astringent, or how sweet. And then they will use those newly agreed upon standards to evaluate a given product.
Similar work is conducted throughout the cheese world. Tasting is an essential part of the WSU Creamery’s daily routine. MaryAnne Drake ’96 PhD heads the sensory evaluation program at North Carolina State University, which specializes in dairy products, and has developed a cheese flavor wheel and an exhaustive lexicon for cheddar cheese.
The object of Ross’s scrutiny may be a raspberry newly released by Puyallup breeder Patrick Moore. Or a wine aimed at a specific segment of the market. Or an apple moved forward in apple breeder Kate Evans’s trials. The sensory evaluation of Cougar Gold, on the other hand, will never produce another version, but rather ensure that it always tastes the same. Thus, the perfect pairing will endure.
So many apples…
Although the apple has found its way into thousands of preparations, both sweet and savory, the whole unprocessed apple is still its most consumed and appreciated form.
But much has changed over the last decade or so. For years, the Red Delicious ruled, particularly in Washington. Although it originated as a chance seedling in Iowa in the nineteenth century, it adapted beautifully to Washington’s growing conditions. In fact, so confident was the Washington apple industry in the “Red” that the state did not even bother with a breeding program. At its height, the Red Delicious represented more than 60 percent of the Washington apple crop. (Although it has dropped to approximately 34 percent of the state’s crop, it is still the most widely grown variety. Indeed, there are still older strains of Red Delicious, not the purest red, that are quite good.)
And then, a couple of things happened. Over the years, growers became so enamored of the Red’s color that they selected sports, mutant branches bearing redder apples, which they propagated toward a redder and redder fruit. (The original Red Delicious, the Hawkeye, had red stripes over a yellow-green background.)
A funny thing happens as an apple gets redder. Its flavor decreases.
Although others had started to grow concerned over how little flavor remained in this admittedly gorgeous apple, it was post-harvest horticulturist John Fellman who figured out what was happening.
“We proved…that as they selected for color, there’s only so much metabolite to go around. Since the pigment is in a subset structure called the vacuole in the skin, metabolite gets grabbed and stuck as color.
“As that happens, it means less of the common metabolite for aroma chemicals.”
At the same time, after years of decline in the diversity of apple varieties available in the market, people started to realize that there were indeed apple tastes other than the sweet cardboard that the reddest of the Reds offered. Marvelous-tasting apples from New Zealand started appearing in the grocery store, in late spring and early summer. Suddenly, stores that had once been limited to Red Delicious and the unrelated Golden Delicious started offering people a steadily growing choice.
Some growers became uneasy and started thinking outside the Red Delicious apple box. And Bruce Barritt, a raspberry breeder in Puyallup, moved to Wenatchee to start planting seedlings toward creating a Washington apple-breeding program.
Twenty years later, WSU’s current apple breeder, Kate Evans, sits at a large counter covered with scores of apples waiting to be tasted. Yellow, green streaked with red in multifarious combinations, red with hints of green poking through, the apples are but a small sample of the offspring of Evans’s breeding program. Every Thursday throughout the fall here at the Tree Fruit Research and Extension Center in Wenatchee, she and her laboratory assistants taste the fruits of their labor, searching for the next big thing.
The apples are a combination of seedlings, apples never tried before, apples that have been carried forward in the breeding trials, and controls. The Gala generally serves as a middle-of-the-scale control, both for production systems and sensory evaluation.
Evans is part of a large multi-scientist, multi-university, and USDA project, RosBREED, which aims to better understand the genomes of fruit throughout the Rosacea family, which includes apples, peaches, and cherries.
One of the initiatives within the project is to identify flavor gene markers. Geneticist Cameron Peace has been hunting down such markers in the apple that may eventually give breeders more control and precision in creating new varieties with desired flavors.
“The holy grail,” says Fellman, “is to have a whole suite of these markers for breeders, so they can select without taking seven years to get fruit.”
But that grail is so far undiscovered. In terms of aroma and volatiles, markers have proven elusive. However, says Evans, she does use such markers that indicate acidity.
“We have a couple of markers at a site on the genome, an area which has a lot of fruit quality traits,” says Evans. That area includes a gene for malic acid, the principal acid in apples.
“There seems also to be some control of juiciness and crispness in that area, so it’s a really interesting section of DNA that has got a fairly large contribution to fruit quality.”
Even once the markers are identified, using that knowledge does not mean a breeder can simply pick a promising gene and insert it in a seed. Rather, it is a means of better understanding what traits are in the germplasm. Evans uses the marker for acidity to weed out seedlings with insufficient acidity at the beginning of the selection process.
“We’re more interested in applying it early, so we can screen out poor material without having to spend time and money propagating and growing them out for several years, putting them out in an orchard and waiting for the fruit.
“It’s much more efficient.”
So far such selection has been at the very beginning of the process. Evans does not use the information to move a candidate from phase one to phase two of the breeding program, simply because identifying a marker is only part of the overall picture.
“But it is something that Cameron is working on in terms of what he calls ‘decision confidence,’” she says. “He’s hoping that by putting more molecular data in with data that we’re producing from tasting or instrumental measures it will help make a more complete case to industry.”
The perfect pair
To some extent, looking for the perfect apple means looking for a perfect balance between acidity (tartness) and sweetness. A merely sweet apple may please some palates, but is really quite boring. (Though I’m told there are actually people who like the Fuji.) With nothing to offset the sugar, an apple lacks depth and dimension. It is flaccid and dull.
A merely tart apple, on the other hand, can be equally unsatisfying. The Granny Smith, a New Zealand apple that gained favor with the American public when all the good American cooking apples had disappeared from the market, is also generally picked too early and is just sour.
But when an apple is balanced sweet and tart—a well-ripened Golden Delicious, the Braeburn, Pink Lady, and WSU’s new offerings, as yet unnamed—one realizes that perfection is indeed attainable here on earth. Particularly when enjoyed with our own Cougar Gold.
Cougar Gold is what we do best. In searching for a culture to offset the production of carbon dioxide in a cheddar cheese so that it might be packed in a can and sent to troops in Europe, N.S. Golding, a professor of dairy husbandry, inadvertently discovered the “magic flavor culture” that moves an otherwise solid cheddar into the highest realms of cheese possibility.
The task of keeping it Cougar Gold, which represents 80 percent of the Creamery’s sales, is not an easy one.
Russ Salvadalena, the director of the WSU Creamery, thinks of his operation as both artisanal and fairly large. What distinguishes it from many of the smaller cheese-making operations around the state is its diligent quest for consistency.
Surprise can be wonderful in an artisanal cheese. Yeast and bacteria abound, hanging out in nooks and crannies, floating through the air, waiting for the opportunity to alter a cheese’s flavor.
What sets the Creamery apart from more industrial operations, many of which obviously produce very good cheese, is not only its unique quality and flavor, particularly of Cougar Gold, but also, again, its consistency.
When an eager customer opens a can of Cougar Gold, what he or she anticipates is exactly that: the taste of Cougar Gold.
Every day the Creamery folk analyze the milk that comes in from the campus herd of Holsteins, for butterfat and protein. Butterfat content is the easier to adjust, by adding cream.
Various factors throughout the year, including the feed the cows are eating and the temperature, can affect the milk’s composition.
Once the milk is deemed appropriate, rennet, an enzyme, is added to break down part of the protein and enable the proteins to bind together around the butterfat globules.
A cheese culture of lactic bacteria is also added. This is actually one of four cultures that are rotated through the cheese-making cycle, says head cheese-maker Nial Yager. The reason the Creamery maintains four cultures, all of which do lead to the cheddar cheese that is the foundation of Cougar Gold, is their archenemies, the phages. Phages are viruses that attack the lactic bacteria and bring the fermentation of the milk to a halt.
Besides an extreme attention to cleanliness, Yager and his staff rotate the cultures, enabling them to prevent the phages, which are very specific to the individual cultures, from building up.
What sets Cougar Gold apart from an ordinary cheddar is what Yager refers to as their “magic flavor culture,” the one discovered by Golding and nurtured carefully over the past 75 years.
This culture, a trade secret, breaks down the proteins in the cheddar cheese even further, mellowing the acids and giving it that unique Cougar Gold flavor.
Yager and staff transfer the culture from the mother culture to a culture bottle every two or three days, doing so in an isolating glove box to avoid contamination.
As an emergency backup, the culture is also preserved in liquid nitrogen at an undisclosed location on campus.
An added, and essential, daily task is to taste and evaluate the flavor culture to make sure it has not changed.
Although larger, more industrial cheese producers create good cheese, it is the hands-on labor, provided by student workers, that sets Cougar Gold apart, says Salvadalena. The “cheddaring” process is labor intensive. Once the developing cheese has coagulated, salt added to slow the fermentation, the curds cut, and the whey drained, the slabs of new cheese go onto the finishing table, where the workers cut and flip them continually until ready to drain and press and place in the cans. It is this process that gives Cougar Gold the needed attention to achieve the daily consistency.
Large cheese producers make their cheddar with an automated machine called the Cheddar Master. Whereas the Creamery produces one batch a day, the larger producers may do 30. Even under the best conditions, the action of bacteria can alter over the course of a day, and each batch might be slightly different in flavor.
Now, if you may, open a can of Cougar Gold. First, slice off a small bit and chew it slowly: creamy, salty, sharp, nutty, a little bitter. You may notice little crystals, tyrosine—an amino acid and the remnant of casein, the main protein in milk—breaking down.
Now take a bite along with a sweet-sharp Washington apple. This is as good as it gets.
What is a Washington apple?
Washington’s excellence as a place to grow apples is reflected by the fact that we produce better than 60 percent of the U.S. apple market.
“Cool nights and warm days and long hours of sunlight,” says Fellman, summing up our climatic advantage. But there are subtleties involved. Because our nights get so cool during fruit maturation, he says, the carbon produced through photosynthesis during the day is preserved by the plant. It does not get used up through what is called maintenance respiration at night.
“So your net photosynthesis gain is very good, which is why things grow so well here.”
“Also, nowadays, breeders are actually tasting fruit,” he says.
“Well, that’s always been the case,” says Evans. “What happens is growers select for color.”
Even so, there is some truth in Fellman’s overstatement. Altering a plant’s genetic signature always involves some tradeoffs. An apple might be the most delicious thing in the world, but if it does not ship well or hold up in storage or if it turns to mush three weeks off the tree, that wonderful flavor alone is not going to make anyone any money.
Indeed, to an extent, such is the case with many older varieties of apples. Varieties such as Smokehouse, Wealthy, Belle de Boskoop, Calville Blanc d’Hiver, and many others have wonderful, complex, and tantalizing flavors right off the tree, making them excellent for a connoisseur’s backyard or local farm market. Indeed many older uniquely flavorful varieties are making a comeback, but if they don’t keep or travel well, no large grower with a bottom line in mind is going to plant them.
Developing an apple that tastes great and keeps well is Evans’s challenge. And that challenge has grown greater with the increasing competition, Washington- and foreign-grown, in the market.
Add to that the challenge of producing a variety for Washington growers that stands out in the market. Not only must it taste great, it must grow well here, it must look great (the wow factor), and people must pay for it.
And they will take a bite and say, that must be a Washington apple!
Evans starts her breeding from varieties that do well here, she says. Typically, more varieties do well here than not.
“We look at the parents on an annual basis, look at how the fruit is doing and how the parents are performing in our climate.”
But that is hardly straightforward. Even central Washington, where most of our apples—and grapes—are grown, is hardly homogeneous in terms of climate, soil, and other environmental factors.
Indeed, the test sites that Evans uses are fairly extreme, but they reflect the diversity of growing conditions. For Phase Two selections, sites include an organic orchard at Lake Chelan—high elevation, cold, exposed, late-blooming and late-maturing—and a site down toward Richland, which is very hot and early.
When an apple is chosen for Phase Three, which currently includes four “elite” selections, the sites become even more demanding: Brewster, Quincy, Mattawa, and Prosser.
But beyond the challenges of producing a delicious and profitable apple, Evans believes the importance of flavor is coming back.
The threats to flavor are great, prime among them mass production and consumer expectations.
“We want our fruits and vegetables all year,” she says. “We expect to have strawberries and tomatoes all year round, expect apples all year round.”
In order to satisfy those expectations, apples are treated with 1-MCP (methylcyclopropene) to retain texture throughout storage. 1-MCP inhibits apple sensitivity to ethylene, a chemical produced by the apple itself that induces ripening. 1-MCP thus delays not only softening, but aroma production.
Fruit produces flavor volatiles only when it matures, Evans says. So producing fruit on such a scale is inevitably a great compromise.
But Evans seems primed for the challenge. In spite of the odds, but also with improving horticultural and genetic tools, Washington apples will continue to prevail.
And provide the perfect complement to Cougar Gold cheese.
On the web
Taste + aroma = flavor
Taste all by itself is what you experience when you have a really bad cold clogging the pathways that sense the more elusive aromas, says sensory scientist Carolyn Ross.
Sweet, sour, bitter, salty, umami. Sure, they’re fundamental and promise seemingly endless combination potential, but a cold is a good reminder that basic tastes without the subtler flavors can get pretty boring.
Fortunately, we normally have two chances to experience flavor: before we taste and in conjunction with taste.
The initial aromas of a wine or an apple go up your nose, referred to as orthonasal olfaction.
You experience those aromas again once the wine is in your mouth, the retronasal.
You will taste the wine’s sweetness, acidity, and slight bitterness. But the true pleasure of a fine wine lies in its more subtle aromas.
Much of your experience of aroma, says Ross, is played against previous experience. Whereas taste derives from a more fundamental survival origin, the sense of smell—the detection of aroma—is more tied into the limbic system and thus more associated with memory and emotion.
“When you smell something, you might recognize it or it reminds you of something, but you can’t quite put your finger on it.
“It’s called ‘on the tip of your nose’ in the sensory literature,” she says, smiling.
Humans have about 10,000 taste buds, variously distributed, mostly on the tongue, which detect the five basic tastes. Rabbits, on the other hand, have about 17,000 taste buds. Cows have 25,000. And catfish? 100,000.
Before you feel gustatorially or evolutionarily slighted, however, you should know that the chicken has only 17.
And we might consider what these numbers are all about. Think, for example, about the catfish’s general situation. A bottom-feeder, the catfish must search through the gloom and muck for anything edible, let alone nutritious and delicious. It needs a lot of taste buds, many of them on its whiskers, to find its food in a muddy river bottom.
Given that cows consume primarily grass, one can only imagine the varieties of flavor and corresponding nutrition spread across ancestral grasslands that ultimately required that many taste buds to give cows their current discretion.
And given that humans are broadly omnivorous, feasting on an enormous range of food, from berries to pork chops, those 10,000 taste buds seem to have served us well indeed, at least from an adaptive and survival perspective.
Although we have only one or two taste receptors for sweetness, we have dozens for bitter, strongly suggesting that our tastes developed as a means of survival. Sweetness, a complex of many chemicals, indicates energy-rich nutrients, which are particularly important for feeding our brains.
Salt indicates necessary ions for electrolyte balance.
Bitter, on the other hand, generally indicates toxicity in the wild in many forms. Bitter compounds can include everything from peptides and esters to terpenes and methylxanthines like caffeine. Whereas one can taste saltiness at a concentration of one part in 400, bitterness can be detected at a concentration of one in two million.
Sour taste comes from acids, which can indicate both fermentation and rot. It can be tasted at a concentration of one in 130,000.
Umami, the most recently identified taste, indicates the presence of amino acids such as one might find in cheese or meat broth. Umami is generally savory.
For those of us who eat and imbibe for reasons beyond mere subsistence, those survival mechanisms have combined with the olfactory detection of subtler aromas and volatiles to give us flavor.