ARS | Publication request: Effect of UV-B light on soluble phenolic compounds and antioxidant capacity of various specialty crops and pomaces

Submitted to: Institute of Food Technologists
Publication Type: Abstract Only
Publication Acceptance Date: February 18, 2010
Publication Date: N/A

Technical Abstract: UV-B treatment is the basis of a novel value-added processing method that enhances the nutrient content of specialty crops by increasing the synthesis of terpenes, polyphenolic compounds, and nitrogen-containing compounds. Whole fruits and vegetables and thin layers of peel and pomace by-products were exposed to different total energy doses and peak irradiances UV-B light and then incubated at 15 °C for 72 h to allow the samples to respond. Whole carrots and carrot peels exhibited an 85% and 22% increase in total soluble phenolics (TSP) after exposure to UV-B light, respectively. Antioxidant activity increased as UV-B dose increased. Strawberries showed a significant but slight increase in TSP. Whole grapes, blueberries, and industrial pomaces from baby carrot manufacture, cold-break tomato paste process, wine grape processing, and cold-press olive oil extraction did not benefit from UV-B exposure. Leaching of soluble polyphenolic precursors and mechanical cell damage during processing are likely responsible for the lack of response of industrial pomaces to UV-B treatment.