SCIENCE AND CULTURE

Vegetable breeders turn to chefs for flavor boostCarolyn Beans, Science Writer

Last August, four chefs sat around a table in aMadison, WI, restaurant, each with small samplesof 10 tomato varieties. With nary a word spoken, thechefs tasted each morsel, then rated the flavoralong dimensions represented by axes drawn onpaper. Tomatoes high in sweetness and acidity fellon the right. Those high in umami, a savory flavor,were grouped in the bottom left.

Tomato flights aren’t the latest food trend, andJulie Dawson, the woman overseeing this event, wasnot administering a culinary exam. Dawson, a plantbreeder at the University of Wisconsin–Madison, isone of a small but growing number of breeders whoare harnessing the power of the chef’s palate to pro-duce more flavorful vegetables.

Most of the tomatoes the chefs tasted that day werevarieties in the making. The chefs’ input helped deter-mine which varieties hit the seed catalogues, which werebred with others to improve flavor, and which were

dropped from production altogether. “Chefs can articu-late what tastes good andwhat needs to be fixed in waysthat others can’t,” says Dawson.

Breeder–chef partnerships vary in approach fromquantitative analyses to informal conversation, but allare centered on the basic idea that when breeders andchefs unite they can revolutionize the quality of produce.

Flavor Lost and FoundPeople have crossed plants and selected the mostproductive, disease-resistant, attractive, and flavorfuloffspring for millennia. But as we came to rely on foodgrown at a distance, taste dropped out of the equa-tion. “People have been breeding for durability dur-ing shipping and shelf life, so they haven’t put theeffort into consideration for flavor,” says plant breederand geneticist Jim Myers of Oregon State University.

Many breeders care about flavor but can’t affordthe time and money necessary to select for it. A single

Fig. 1. Chefs with expert palates are helping plant breeders revolutionize the flavor of produce. The owners of theOregon-based, organic seed company, Adaptive Seeds—Andrew Still (Second from Right) and Sarah Kleeger (Left)—walk their fields with Oregon State University agricultural researcher Lane Selman (Right) and local chef Timothy Wastell asthe team develops new varieties of kale. Image courtesy of Shawn Linehan (photographer).

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breeder may need to taste hundreds of different linesof a particular crop each year. Or a breeder may relyon sensory panels, groups of 10 or more people wholearn a common vocabulary to provide precise de-scriptions of flavor components, such as acidity, sugar,and umami, a process that can last weeks or months.

Chefs can make the selection process easier forbreeders because they have experience assessingflavor. “Chefs have highly trained palates,” saysMyers. “They’re used to tasting foods and decon-structing them so they understand flavors and nu-ances.” And chefs have much to gain from gettinginvolved. “I want better tasting, better performingvegetables to use,” says Timothy Wastell, chef atAntica Terra winery in Oregon. “Food is only as goodas the ingredients you are using, so it’s a no brainerthat the food will get better when the produce getsbetter.” Food also tastes better when it is fresh fromthe farm, says Wisconsin-based chef Tory Miller,who works with local breeders, in part to help themdevelop a greater variety of crops suited to thelocal climate.

Chefs and Breeders UniteChef Dan Barber was one of the first to recognize thepower of the chef–breeder partnership. In 2013, heinvited Dawson, Myers, and about a dozen otherbreeders to attend a summit along with about 60 chefsat the Stone Barns Center for Food and Agriculture inPocantico Hills, NY, a nonprofit education center thatis partnered with Barber’s onsite restaurant, Blue Hillat Stone Barns. There, Barber laid out a vision for howchefs, breeders, and farmers could work together toproduce vegetable varieties that are both highly pro-ductive and flavorful. And maybe, if vegetables tastedbetter, people would eat more of them.

Vegetable breeder Michael Mazourek of CornellUniversity helped organize the event. He and Barberstarted collaborating in 2009 after Barber hosted adinner for Cornell plant breeders and served one ofMazourek’s squash varieties. The dish’s flavor andpreparation so impressed Mazourek—Barber cookedthe squash hotter and longer than cookbooks oftenadvise—that Mazourek decided to start selecting for avariety that best fit this culinary technique. Mazoureksays he valued working with someone who appreci-ated the more creative aspects of plant breeding—selecting for unusual colors and textures, flavors, andshapes. He wanted that experience for other breedersas well. “I had all these peers that were working on alltheir coolest projects, but they weren’t showing othersbecause the [produce] wasn’t mainstream enough,”Mazourek says.

Dawson returned from New York and teamed upwith Tory Miller of L’Etoile Restaurant, who alsoattended the summit, and a handful of other localchefs. Together the group started the Seed to KitchenCollaborative, now in its fourth summer. Each year,breeders from across the country give Dawson seedsfor as many as 40 different candidate varieties each ofabout a dozen different crops. The varieties are alldeveloped through traditional plant crosses, because

many will be grown on organic farms that don’t allowgenetically modified seed.

Dawson plants the seeds and monitors them fordisease resistance, yield, and cold tolerance. Afterharvest, about 10 to 20 university students rate the va-rieties on a scale from 1 to 5 for characteristics such assweetness, bitterness, and acidity. Dawson then incor-porates the students’ responses into a principal com-ponent analysis (PCA), a statistical technique that allowsher to group varieties with similar combinations of flavorcomponents while determining which components aremost important for setting varieties apart. She chooses

a sampling of varieties that span the flavor spectrumand presents these to chefs during a monthly tasting.

The chefs sometimes create flavor maps as theydid for tomatoes last year. They also fill out ques-tionnaires with open-ended questions, such as “Whatis the best trait of this variety?” The chefs then discusswhich varieties they’re excited about. During lastyear’s tomato tasting, Miller was wowed by the “in-credible amount of umami” in some varieties.

The results give those tired of bland tomatoesreason for hope. In each tasting, Dawson adds anexisting modern variety and an heirloom variety ascontrols. Some of the new lines developed bybreeders who select for both flavor and productivityare beating the heirlooms in the flavor category.“There might not be as much of a tradeoff as we

Fig. 2. By offering feedback at vegetable tastings hosted by University ofWisconsin–Madison plant breeder Julie Dawson, chefs in Madison, WI, influencethe flavor profiles of vegetable varieties in the making. Pictured Left to Right:Jonny Hunter, Julie Dawson, Tory Miller, and Dan Bonanno. Image courtesy ofGerhard Fischer (University of Wisconsin–Madison, Madison, WI).

“What we are trying to do in a nutshell is to force thegrowers to grow more good-flavored stuff because theconsumers are demanding it, and that’s where the chefsbecome really powerful.”

—Henry Klee

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thought between production and flavor,” Dawsonsays. “We just have to select for both.”

Getting to MarketAlready, Dawson’s group has helped convincebreeders to move forward with commercial varieties.One success, ‘Garden Gem,’ is a cross between amodern, high-yielding tomato and an heirloom. To-mato breeder and molecular biologist Harry Klee ofthe University of Florida developed the tomato andformed a 100-person consumer taste panel. He foundthat its flavor rivals the heirloom parent but with two tothree times the yield. When Klee trialed the ‘GardenGem’ in Dawson’s program, the chefs rated it highly.Citing the chefs’ approval helped Klee win over onlinegrocer Fresh Direct, which contracted with a Penn-sylvania farmer to grow the tomato. “What we aretrying to do in a nutshell is to force the growers togrow more good-flavored stuff because the con-sumers are demanding it, and that’s where the chefsbecome really powerful,” says Klee.

In another chef–breeder collaboration, Mazourekworked with Barber to create the ‘Honeynut’ squash, across between butternut and buttercup squash varie-ties. Barber promoted the hybrid at his restaurant; itthen spread to farmer’s markets, Trader Joe’s, andBlue Apron. Mazourek likes to cut a squash in half,taste one side, and ship the other to Barber. They thenchat about what qualities work well and what couldbe improved.

Myers, after collaborating with Oregon State agri-cultural researcher Lane Selman and garnering chefinput, is nearly ready to release a haba~nero pepperthat boasts flavor without heat. “While we haveworked closely with farmers to make sure that weget their input into the breeding process, we didnot originally have much effort on evaluating tasteand quality,” says Myers, who is the project directorof the Northern Organic Vegetable ImprovementCollaborative, a program to breed vegetables fororganic farmers.

Selman now runs the Culinary Breeding Network(CBN), a group of plant breeders, seed growers,farmers, chefs, and produce buyers. Since 2014,she’s hosted the annual CBN Variety Showcase, atasting event where chefs pair with breeders to

present novel varieties and preparations to foodenthusiasts. “The breeder will get more feedback inthat evening than they will for the rest of the year,”says Selman. At last year’s event, chefs from TomDouglas’ restaurant group impressed guests by fla-voring soda with Myers’mild haba~nero peppers. Thisyear, Selman expects 500 attendees and 25 breeder–chef teams.

Selman also works with the organic seed com-pany Adaptive Seeds to select new varieties of kalethat have attractive leaves and unique flavors anddo well on organic farms. Chef Wastell walks thefields with the company’s owners, tasting the leafygreens as he goes and noting which are sweet,tangy, or pleasantly bitter.

The Human ElementBut Klee is more interested in catering to the publicthan to chefs. To make the perfect supermarket to-mato, he’s taking a molecular approach, identifying13 key flavor chemicals and the underlying genesthat modern tomato varieties lack (1). He is nowsystematically crossing plants to breed those genesback in while maintaining the traits that make thetomato profitable for farmers. Klee says he prac-tices traditional plant crossing, as opposed to ge-netic engineering, in part because he doesn’t feelhe could recover the expense associated with get-ting government approval to release a geneticallymodified crop.

Dawson also wants to incorporate genetic analysesinto her breeding process. But instead of homing in oneach precise gene that contributes to a flavor profile,she’s attempting to correlate collections of genes withinformation about flavor taken from surveys. Matchinggroups of genes with particular flavor profiles could,for example, yield a sort of genetic fingerprint for adelicious carrot; that signature could then, Dawsonsays, help weed out some obviously unpalatable va-rieties early in the breeding process.

But Dawson doesn’t think this molecular approachcould ever replace her chef collaborators. “I think thata lot of good flavor can be in some surprising placesand I’m not sure if an algorithm or even genetic pre-dictions could actually capture what tastes good,” shesays. “You’ll always need that human element.”

1 Tieman D, et al. (2017) A chemical genetic roadmap to improved tomato flavor. Science 355:391–394.

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