Making sweet corn sweeter is on the plate of Iowa State researchers

Summer is the smell of cut grass, weekend barbecues and — especially in Iowa — the taste of sweet corn, which few people know better than Alan Myers.

He’s made a career out of investigating the Midwest summer staple.

“I’ve been working on corn specifically for 35 years,” said Myers, an Iowa State University professor of biochemistry, biophysics and molecular biology since 1987, who has made it his “maize” mission to amplify the experience by making sweet corn sweeter.

“What I'm trying to do is change the quality of the sweet corn,” Myers told The Gazette. “Like the way the kernels taste when you bite into it, how desirable it is to consume it.”

Sweet corn is being celebrated this weekend at the annual St. Jude’s Catholic Church Sweet Corn Festival in northwest Cedar Rapids, where volunteers have shucked some 18,000 ears of corn to prepare.

Festivities include carnival rides, entertainment, games and food — including, of course, hot buttered ears of sweet corn.

Myers for years has been collaborating with corn-researching colleagues nationally to improve the genetic foundation of sweet corn, address supply chain issues and get more of the crisp yellow kernels into the hands and mouths of consumers.

“I’ve been collaborating with these same groups for like 15 to 20 years,” he said, pointing to the U.S. Department of Agriculture’s National Institute of Food and Agriculture as the funding source, offering competitive research grants for a wide range of crops like tomatoes and blueberries.

“But there’s also one for sweet corn,” he said.

The most recent USDA-funded sweet corn research, run through the University of Florida, offered scientists $8 million to — among other things — develop new breeding tools, improve early-season tolerance and determine factors driving consumer preference.

The $800 million in American sweet corn grown annually accounts for about 1 percent of the country’s corn production — which is dominated by field corn. Sweet corn consumption has been trending down for decades.

“The economic analysis will identify the breeding technologies and traits that have the highest potential return and (will) educate breeders, growers, and processors on the most promising innovations,” according to a USDA project summary of the research that identifies sweet corn as the fifth most popular vegetable in the country.

“Breeders need to be able to address emerging challenges for the crop,” according to the USDA. “For example, the percentage of fresh market corn that is shipped across the country is increasing and sweet corn needs to have a longer shelf-life.”

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'High sugar content’

Distributed from the primary $8 million grant are subcontracts, and ISU has two of about a dozen, according to Myers. “About 10 percent of the total government grants to work on sweet corn are coming to Iowa State labs,” he said.

The collective corn research is broad — from genetic changes to grocery store marketing.

“I'm at the very beginning part, trying to change around how the kernel tastes,” he said. “After that, breeders would take that information and try to breed it into the sweet corn lines to continually improve the quality, in terms of the way it tastes.”

Myers’ specific work looks into how kernels store the sugar transferred from an ear’s leaves — noting sweet corn owes its sugary appeal to a genetic mutation stopping the glucose collecting in its kernels from turning into an insoluble starch.

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Kernels packed with soluble glucose are sweet and juicy, rather than the hard and crunchy field corn version. A second type of sweet corn developed about 20 years ago doesn’t have the same texture as traditional roadside sweet corn — making it better for freezing and canning.

“What we really want is to combine that favorable mouth feel with high sugar content,” Myers said.

His team is investigating what enzymes affect the corn kernel architecture, using gene-editing tools to make adjustments. Although the main mission is to sweeten the crop, the research also could help combat pest and disease threats.

“Finding different changes in the biochemical process to produce sweet corn would secure the crop against future challenges,” Myers said. “We may never need to deal with that, but we want to be prepared.”

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'Big acceleration’

Separate from his work, Myers’ colleague and ISU agronomy professor Thomas Lubberstedt — with the university’s second sweet corn-related USDA grant — is taking the corn-improvement baton into the field.

“He has a method of breeding corn that speeds up, by like four years, how fast you can get a line from its initial construction, which is what I do,” to the field, Myers said.

And if his team develops a good variety with the right combination of genes, he said, “then it has to get into a production line that a farmer can use to produce it and bring it to market. And Thomas’ research is a method to speed that process up from like five years to two years. It’s a big acceleration.”

To the question of whether Americans can expect a sweeter version of sweet corn on their plates at some point in the future, Myers said, “Yes, definitely.”

“Whether it will come directly from my own research, I can’t say,” he said. “It's possible. But the overall effort is really improving the crop.”

Vanessa Miller covers higher education for The Gazette.

Comments: (319) 339-3158; vanessa.miller@thegazette.com