Carrots' antioxidant value boosted by ultraviolet light

January 6, 2011 By Marcia Wood
Carrots' antioxidant value boosted by ultraviolet light
Sliced carrots exposed to UV-B ultraviolet light can have higher levels of antioxidants. Credit: Roberto Avena-Bustillos.

Exposing sliced carrots to UV-B, one of the three kinds of ultraviolet light in sunshine, can boost the antioxidant activity of the colorful veggie. That's according to preliminary studies by U.S. Department of Agriculture (USDA) research food technologist and research leader Tara H. McHugh. She is with the Agricultural Research Service (ARS), USDA's chief intramural scientific research agency.

Found primarily in fruits and vegetables, antioxidants are that may reduce risk of cancer and .

The carrot investigation, conducted by McHugh, postdoctoral associate Wen-Xian Du, and others at the ARS Western Regional Research Center in Albany, Calif., suggests that a moderate, 14-second dose of UV-B can boost fresh, sliced carrots' antioxidant capacity by about 3-fold. The dose is energy-efficient and does not significantly heat or dry the carrots.

Scientists have known for at least a decade that exposing plants to UV-B may cause what's known as abiotic stress. That's what probably happened with the sliced carrots.

Plants respond to the stress by revving up their production of two natural enzymes, one with the tongue-twisting name of polyphenylalanine ammonia-lyase, and the other known as chalcone synthase. As production of those enzymes increases, levels of —antioxidants synthesized by the enzymes—also increase.

Despite this and other knowledge about plants' responses to stress and to UV-B, the idea of using UV-B to quickly, safely, and conveniently enrich the antioxidant heft of fresh produce has not been extensively studied, McHugh notes. The carrot research is helping fill in that knowledge gap.

Explore further: Mushrooms as good an antioxidant source as more colorful veggies

More information: Read more about the research in the January 2011 issue of Agricultural Research magazine.

Related Stories

Edible food wrap kills deadly E. coli bacteria

November 16, 2006

Researchers have improved upon an edible coating for fresh fruits and vegetables by enabling it to kill deadly E. coli bacteria while also providing a flavor-boost to food. Composed of apple puree and oregano oil, which acts ...

Genetically modified carrots provide more calcium

January 14, 2008

A specially developed carrot has been produced to help people absorb more calcium. Researchers at Texas A&M AgriLife’s Vegetable and Fruit Improvement Center studied the calcium intake of humans who ate the carrot and found ...

Radical Scavengers in Red Smear Cheeses

December 15, 2008

( -- Carotenoids not only give carrots and red smear cheeses, such as Munster, Limburger, and Romadur, their characteristic red color, but they also protect organisms from oxidative stress. A research team headed ...

Carrots cooked whole contain more anti-cancer compound

June 17, 2009

Chopping up your carrot after it has been cooked boosts its anti-cancer properties by 25 per cent, scientists at Newcastle University have found. The study, carried out by Newcastle University’s Dr Kirsten Brandt and researcher ...

Recommended for you

'Hog-nosed rat' discovered in Indonesia

October 6, 2015

Museum of Natural Science Curator of Mammals Jake Esselstyn at Louisiana State University and his international collaborators have discovered a new genus and species on a remote, mountainous island in Indonesia. This new ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

3 / 5 (1) Jan 07, 2011
I hope they are also checking to see what the effect is on beta carotene whilst they're busy looking at the other anti-oxidants.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.