Last fall, when the “Gastropod” podcast came to UW–Madison to participate in the 2018 Wisconsin Science Festival, hosts Cynthia Graber and Nicola Twilley asked Irwin Goldman PhD’91 to be a guest on the live show. A professor and chair in the horticulture department, Goldman is a plant breeder and geneticist who focuses on carrots, onions, and beets, and outreach is a regular part of his job. Naturally, he said yes.
Many people enjoy learning about vegetables, and Goldman loves talking about them — and he’s good at it, always ready to serve up fun facts and stories with a dash of science. He’s a popular teacher and a sought-after media expert. You may have heard him on the radio — he’s been a regular guest on Wisconsin Public Radio’s “Garden Talk” for decades, one half of the veggie expert duo known as the “Vicars of Vegetables.”
To help prepare for his “Gastropod” appearance, Goldman met up with Graber and Twilley at the UW Carrot and Beet Lab, where he stores the materials and tools for his plant breeding programs. As they sampled a variety of carrots — the focus of the upcoming show — the conversation shifted to the subject of beets.
“Cynthia told me that she doesn’t eat beets,” recalls Goldman. “She said, ‘I hate beets. I can’t stand them.’”
For Goldman, who loves beets right down to the center of their “beet-y” little hearts, it’s a discouraging sentiment. But it’s one he’s heard many times before. If one of Goldman’s vegetables needs a champion, it’s definitely the beet. It’s a rather polarizing plant.
To many children, beets are pickled horrors that should be avoided at all costs. To some, they constitute peasant food, a steaming bowl of magenta borscht. To others, they are the star attraction of a gourmet salad, roasted to perfection and tossed with arugula and goat cheese in a vinaigrette dressing.
“If you talk to consumers about beets, you’ll find a few people that say they love them and can’t get enough of them, but you’ll find many more who say, ‘I can’t stand them because they taste like dirt,’” says Goldman.
And so they do.
Beets contain geosmin, a compound with a distinctly earthy smell and flavor. It’s the same molecule responsible for the aroma of freshly plowed fields and newly turned garden beds.
Geosmin has been associated with beets since the beginning of time, notes Goldman. His beet breeding program, however, has come up with some new options for people who don’t dig the earthy pungency of the typical beetroot. And it’s developing more.
These options are the result of a career that has taken some surprising turns over the years. After starting with a focus on serving the traditional beet industry, Goldman’s program abruptly expanded to include culinary beets for gourmands and foodies. He set out to develop an un-beet-y beet, something a kid could like, and then went on to crack a long-standing beet mystery central to the vegetable’s earthiness.
At the Carrot and Beet Lab, Graber tried some of these new un-beet-y varieties. “I cut them up, and Cynthia could not get enough of them,” says Goldman. “We just chowed an entire beet, and she was like, ‘This doesn’t taste like a beet.’” Indeed. It’s meant to be something entirely new.
Beet were originally cultivated in the Mediterranean region as a leaf crop. The plant’s greens were harvested for salad while the small, bitter roots were largely ignored. Over time, pushed by the need for crops that could overwinter in more northern latitudes, people selected for larger and larger root size, eventually creating the swollen, durable root of the modern table beet.
Table beets are a healthy food, high in fiber, folate, and vitamins A and C. Eastern Europeans brought beets with them when they immigrated to North America in the 1800s and early 1900s, along with carrots, onions, and other root vegetables.
“Root vegetables are the simple, staple peasant food of Eastern Europe,” says Goldman, whose own family tree goes back to rural Belarus. “They are really like part of my family.”
Goldman grew up in Skokie, Illinois, a suburb of Chicago. He always had a proclivity for nature and science. In his teens, he fell hard for the theory of evolution, which continues to be his “favorite idea of all time.” During his undergraduate years, he happened upon a course about plant breeding — which he quickly identified as the perfect profession.
“It dawned on me that evolution is totally analogous to plant breeding — those things are parallel,” Goldman says. “It’s just that plant breeding is driven by humans and the direction they want things to go. I remember getting so excited about that.”
After doing graduate work in soybean and pea breeding and postdoctoral research focused on corn genetics, Goldman joined the UW–Madison horticulture faculty in 1992. As the new person in charge of breeding and genetics of cross-pollinated vegetable crops, Goldman was given the choice of what vegetables to work on. He opted to follow in the footsteps of his predecessor, Buck Gabelman, a pioneer of modern vegetable breeding who was the first person to apply certain hybrid corn technologies to vegetables crops, including developing the first beet hybrids.
“There was just this wealth of germplasm developed by my predecessor on beets and carrots and onion, and they’re all biennial crops important to Wisconsin, so I decided I just wanted to keep those breeding programs going,” says Goldman. “Also, there were very few people in the country doing those crops.”
Wisconsin has a long history of vegetable canning, including peas, corn, cabbage, snap beans, and beets. Today, Wisconsin is the nation’s top producer of table beets. State producers grow more than 50 percent of the country’s crop, and the majority of the harvest is processed for canning.
In terms of acreage, however, it doesn’t add up to much. There are only around 5,000 acres of beets grown in the state, compared to 2.3 million acres of soybeans, 3.9 million acres of corn, and 68,000 acres of potatoes.
This makes beet a minor crop, and, as such, there aren’t many plant breeders working to improve it. Right now, Goldman is the nation’s only plant breeder at a public institution who works on table beets, making UW–Madison a key resource for all things beet research and breeding. This includes the development of new and improved varieties and serving as a repository for one of the world’s best collections of beet seeds.
“If you go to the store and buy a beet, or you order a beet dish in a restaurant, it’s almost certain to have its origin here in our program, which is cool,” says Goldman. “And it’s not that the [finished] varieties were bred by us, necessarily, but that we supplied the parent materials that companies used to make their commercial varieties.”
One constant since the beginning of Goldman’s career has been his work on agriculturally relevant projects to support the beet industry. One of his first projects involved continuing Gabelman’s efforts to develop high-pigment beets for the production of natural food dyes, a collaborative project with UW–Madison food scientist Joe von Elbe BS’59 MS’60 PhD’64. Goldman and von Elbe, with the guidance of the Wisconsin Alumni Research Foundation (WARF), went on to found a spin-off called Phyto Colorants to make these pigment-saturated beets available to industry. Dyes derived from the company’s beets are now used by national food companies to color ice creams, yogurts, chips, and candies, among other products.
A new project involves developing table beets that are resistant to Rhizoctonia, a soil-borne fungus that is considered a major scourge of the beet industry. Infected beets develop areas of black, dead tissue, which leads to a lot of food waste during processing.
“[Processors] take the beets and peel away the skin. And the deeper the fungus has penetrated, the more tissue they have to take off,” says Katharina Wigg, a plant breeding and plant genetics graduate student who is part of the Rhizoctonia research team.
The project, funded primarily by the Midwest Food Products Association, involves using traditional plant breeding to take a known source of genetic resistance from sugar beets and incorporate it into popular commercial table beet varieties. At the same time, Wigg and Goldman are searching far and wide for a table beet that already has some level of resistance, which, if found, could help speed the breeding effort.
It’s the perfect project for a public plant breeding program. While industry is eager for the fungus-resistant beets, it may take 10 years or more to complete the project, well beyond Wigg’s Ph.D. work.
“We can take on riskier and more long-term projects here, things that private companies can’t do because they need a more immediate return on investment,” notes Goldman.
Goldman’s beet program took an unexpected turn in the late 1990s — thanks in part to the preferences of a celebrity lifestyle guru.
“Martha Stewart began incorporating beets into her recipes, and then it was in Gourmet magazine and Bon Appétit and Cook’s Illustrated,” says Goldman, who shortly thereafter started fielding phone calls about beets — where to buy them, how to grow them, how to cook them.
“[There developed] a whole community of people interested in beets,” he says. “I think about beets as this old-fashioned root vegetable, as peasant food. But now they’ve got this high-end, fancy culinary thing going on,” he says. “There’s been this beet renaissance, and it’s still happening. It’s been wonderful.”
Goldman quickly adjusted his program to meet the new demand for specialty beets, developing new and improved fresh market varieties for restaurants, farmers markets, stores, and home gardens. He’s been working to improve the seed quality of yellow beets so they germinate and emerge better. He’s also nearly finished creating a beet with an entirely novel hue: solid orange.
“You can almost paint these however you like by crossing and using the [pigment] genes that are available. I often feel like I’m playing, like this is an art project,” says Goldman. “But these beets still benefit our farmers. The whole culinary world has exploded for beets, and our farmers want to grow things that people want to eat, so I’m working to develop [more options].”
When this renaissance started, Goldman decided that he wanted to try to develop a beet that his own kids, as well as other beet-averse folks, would enjoy. This launched a 15-year odyssey to develop his Badger Flame series of beets — Badger Flame, Badger Torch, and Badger Sunset — which were released as finished varieties in 2012. These beets, developed in partnership with UW–Madison vegetable breeder Nick Breitbach, are oblong with vibrant yellow, orange, and red interiors. And they’re designed to be eaten raw.
“When you give somebody the Badger Flame beet, you can peel it, and you can just chomp on it like a stick of jicama,” Goldman says. “It’s sweet and crunchy with about as much earthiness as spinach. So you get that hit of sucrose and not the hit of the soil.”
This is the beet that Goldman served to a pleasantly surprised Graber from “Gastropod.”
Badger Flame beets are proving quite popular as far as culinary beets go. The seeds are available for purchase through Row 7, a specialty seed company founded in 2018 by Dan Barber, award-winning chef at Blue Hill at Stone Barns in New York. In February, The New York Times featured the company, which led to a boost in seed sales.
Goldman works with WARF to release the new beet varieties he develops that have commercial potential as well as new inbred lines that seed companies may want to use to produce new hybrid varieties. When companies license his germplasm, the resulting royalties help support more research and breeding.
The Badger Flame project showed Goldman that earthiness can be dialed down in beets. This got him thinking about what’s going on with geosmin in his favorite root vegetable. He wondered: Where do beets get their geosmin? Is it from the soil that they grow in, or do beets produce it themselves?
Soil microbes, particularly certain strains of Streptomyces bacteria, produce geosmin in vast quantities. That’s what makes the soil smell earthy.
“We always thought that [beets are earthy] because they live in the ground and that the soil bacteria were maybe living inside the skin of the beet or something,” says Goldman. “But we didn’t know.”
The effort to solve this mystery started with Amy Freidig BS’07 MS’10 MS’13, one of a series of talented graduate students in the Plant Breeding and Plant Genetics program to work on this long-term project.
Freidig tapped into a new, shared campus resource: a gas chromatograph mass spectrometer, which can measure volatile compounds such as geosmin. She was able to show — in a quantifiable way — that geosmin is cultivar-specific. In other words, different beets have different levels of geosmin.
Next came Lynn Maher BS’11 PhD’17.
“When I joined, the next question was, ‘Can we breed for this?’” Maher says. “The biggest part of my project was to see if we could select for geosmin as a trait.”
While Goldman had already had success with his Badger Flame beets, Maher needed to quantify the geosmin throughout the breeding process to show it changing over time. Maher started crossing high-geosmin lines with other high-geosmin lines and low-geosmin lines with other low ones, trying to increase and decrease geosmin levels, respectively.
And it worked. Very well. For the high-geosmin lines, they raised geosmin levels by more than 50 percent. For the low, the levels basically “hit the floor.”
“As an emerging plant breeder, it was exciting to see that selection really works,” says Maher, who now works for Bejo Seeds, Inc., the U.S. subsidiary of a Netherlands-based vegetable seed company.
Next, to rule out the possibility that some environmental factor could be involved, Maher grew various beet lines in sterile tissue culture. Grown in an isolated, microbe-free environment, the beet-y beets still managed to produce earthy roots. The results, published in HortScience in 2018, were the final proof.
“[We showed that] beets produce geosmin on their own, endogenously,” says Maher.
After Maher graduated, doctoral student Solveig Hanson picked up the reins. On the research front, Hanson is looking for the genetic markers associated with beets’ geosmin genes. On the breeding side, she leads a participatory breeding effort to improve culinary beets with ongoing, direct input from local chefs, farmers, and consumers.
The project, supported by the U.S. Department of Agriculture, is heading toward more diverse beet flavor profiles, including both high-geosmin and low-geosmin beets with various levels of sweetness.
One way Hanson solicits consumer feedback is through tasting events. Last fall, she helped staff the beet table at the UW Farm to Flavor dinner, which features promising vegetables from the university’s various breeding programs prepared by local chefs into gourmet amuse-bouche fare. At the beet table, participants sampled an assortment of roasted roots and filled out a survey about their perceptions and preferences, including selecting from a list of 20 taste-related terms for each beet they tried: caramel, dirt/soil, grass, herbal, mineral, musty, stewed meat, white sugar, and so on.
“We want to come up with a flavor lexicon — a flavor vocabulary — that helps people describe flavors and tell varieties apart,” says Hanson, who plans to organize the top terms into a “flavor wheel,” a handy descriptive graphic. “We hope this will help farmers describe flavors to their customers and help plant breeders describe flavors to farmers looking for seeds to buy.”
At the recent Farm to Flavor dinner, Hanson found it interesting that beet table visitors seemed to like the high-geosmin and low-geosmin varieties about the same. And, whether earthy or not, people consistently expressed a preference for sweeter-tasting beets. Overall, she takes it to mean that there’s room for all kinds.
“What things are pointing to is that there are a range of appealing flavor profiles in beets, which is really exciting for the specialty beet marketplace,” says Hanson. “I think there’s an explosion of diversity in beet that is still to come, and I think there’s space in the market — and space in people’s palates — for it.”
Goldman, who sees himself as a steward of beets for the public good, is committed to pushing the field in new and promising directions. He’s proven that he’s willing to do what needs to be done to ensure his beloved root vegetable has a bright future — including, in certain cases, expunging the very essence of what makes a beet a beet. And he has made peace with that.
“Initially, I felt bad about creating something that was un-beet-ish, because it seemed like that was the opposite of what my job should be, in a certain way,” he says. “But it has been very gratifying because more people have gotten into this vegetable, more people have started experimenting with it. It’s like a vegetable gateway drug to enjoying other beets.”
Plant Breeding: ‘The Slowest of the Performing Arts’
The table beet is a biennial plant. That means, left to its own devices, a beet plant takes a full two growing seasons to complete its life cycle — from a seed planted to a new seed produced. Fortunately for Irwin Goldman, professor and chair in the horticulture department, there’s a low-tech way to go from seed to seed in a single year. Read more.