UV light may boost antioxidants in carrots
January 6, 2011
by Jeff Gelski
ALBANY, CALIF. — A moderate, 14-second dose of UV-B, one of three kinds of ultraviolet light in sunshine, may boost the antioxidant capacity of fresh, sliced carrots by about three-fold, according to U.S. Department of Agriculture researchers at a Western Regional Research Center in Albany. The energy-efficient dose does not significantly heat or dry the carrots. Antioxidants are natural compounds that may reduce risk of cancer and cardiovascular disease.
Exposing plants to UV-B may cause stress. Plants respond to the stress by increasing production of two natural enzymes, polyphenylalanine ammonia-lyase and chalcone synthase. Levels of phenolics, some of which are antioxidants, also increase since they are compounds synthesized by the two enzymes.
Tara H. McHugh, a research food technologist with the U.S.D.A.’s Agricultural Research Service, led the study. Results appear in the January 2011 issue of Agricultural Research magazine. Previously, Ms. McHugh worked with Monterey Mushrooms, Inc., Watsonville, Calif., in using UV-B to increase vitamin D levels in mushrooms.