For the past four years, University of Missouri researchers have been changing the color of corn to see whether purple breeds can provide potential health benefits.
Working with a dark purple South American variety known as maiz morado, the researchers have discovered that its kernels have more antioxidants than blueberries, as well as other nutritional compounds that could be beneficial to health.
Now these researchers are working to extract a red dye from purple corn to replace the petroleum-based Red 3 dye that has been banned by the FDA.
It could also replace another synthetic food colorant called Red 40 that has faced heavy regulation in states such as California because of health concerns in children. Those concerns include allergies, migraines and attention-deficit/hyperactivity disorder, or ADHD.
Pavel Somavat, an assistant professor of food and biological engineering at MU, is one of the leaders of the research project.
Somavat expects a market for natural red dyes to become more pronounced as a backlash against artificial dyes becomes more widespread. This could open a market for Missouri and other corn growers.
“With the changes taking place in California, I do foresee more and more interest,” Somavat said.
Robert Kennedy Jr., the Health and Human Services secretary, told food industry leaders earlier this month that he wants them to remove artificial color additives from their products by the end of his time in office.
Somavat’s research focuses on the corn’s pericarp, or the outer layer of the kernels. Pericarp is often discarded as a byproduct, but a recent study by Somavat’s group shows a way for the pericarp of purple corn to be used to create natural red dyes.
“The corn industry is interested in the endosperm, which contains starch and protein,” Somavat said. The endosperm is the white filling inside the corn kernel.
This variety has an intense shade of purple or red, owing to the abundance of a group of antioxidants called anthocyanins in the pigment. It has been extracted and used for traditional food products, including corn tortillas.
Somavat’s study used different milling techniques with 18 varieties of purple corn and analyzed the results to see which ones had the best potential industrial applications. The uses could include coloring beverages, sweets and dairy products.
Using purple corn as a dye could also have health benefits, such as acting as a source of fiber. The same study found that purple corn is a good source of antioxidants and polyphenols, which have been linked to healthier hearts and immune systems.
With natural dyes, “food is actually getting fortified in terms of nutrition,” Somavat said.
Somavat’s team also explored the corn extract’s use in fortifying an edible film made from various food proteins. Given the corn’s antimicrobial and pest-deterrent properties, the team believes the film could be an alternative to plastic food packaging, which has faced scrutiny in recent years regarding microplastics.
“Microplastic is an emerging danger for human health,” said Sumit Singh Sheoran, a collaborator on Somavat’s project.
A major issue the researchers face is growing purple corn. Because the corn is commonly found in South America, the group has been working with a USDA research geneticist to cross-breed purple corn with more Midwestern varieties.
The solution would move color genes from one variety to a plant that is better adapted to its current environment.
Persuading local farmers to cultivate purple corn could also prove challenging, Somavat noted. Growing corn for its red dye would have to compete with a large market for corn-based ethanol, where yellow corn remains dominant due to its high yield.
“So far, the U.S. corn farmers have been getting very high yields, and the processing industry is oriented toward yellow corn, so people didn’t feel a need … to look for alternates other than yellow,” Somavat said.
Despite America’s preference for yellow corn, Somavat is optimistic that a purple variant, whether as a natural dye, a nutrient-rich food or as a substitute for plastic packaging, will catch on.
“Change is always hard for people to digest,” he said.
COLUMBIA MISSOURIAN