Scientists unveil new method that extracts antioxidant nutrients from corn processing waste
The academics claimed a process for extracting nutritious antioxidant dietary fibres from cornstarch production waste could turn tonnes of nearly-worthless bran into a valuable, circular resource.
Corn bran is rich in the potent antioxidant, ferulic acid. Unfortunately this anti-inflammatory is trapped in an insoluble material matrix that humans can’t digest.
Researchers at KTH Royal Institute of Technology, however, have reported a way to unlock soluble ferulic acid-rich dietary fibres from this insoluble matrix, and they developed a hydrogel that delivers it to the intestines where it can prevent cell oxidation and improve gut health. The method was published in the scientific journal, Green Chemistry.
Due to its insolubility, corn bran is a low-value sidestream from corn starch production, which is otherwise discarded or sold off for animal feed. But instead of letting it go to waste, the researchers used a method called subcritical water extraction to isolate the soluble fiber part of the bran that contains ferulic acid.
Francisco Vilaplana, Associate Professor in the Division of Glycoscience at KTH Royal Institute of Technology, said the next step is to create a hydrogel by crosslinking this soluble ferulic acid-rich dietary fibre part using natural enzymes (laccase and peroxidase). The hydrogel can be digested as a prebiotic for gut health, or even used as a treatment for wounds, since it counteracts oxidative stress and contributes to healing.
The global market for cornstarch is estimated at more than 120 million metric tonnes, and is expected to increase to 160 million metric tonnes by 2026. In cornstarch processing, as much as 15 percent of the kernel is discarded as fibre, or corn bran, Vilaplana says. “That’s a huge industrial sidestream.”
He says the new technique addresses the worldwide concern about food waste, in terms of sustainability and greenhouse gas emissions.
“We showed that we can upgrade a food side stream into a valuable material for both food and biomedical applications that could mitigate inflammatory processes.”
Hydrogels with protective effects against cellular oxidative stress via enzymatic crosslinking of feruloylated arabinoxylan from corn fibre