Dog rose and pomegranate extracts as agents to control enzymatic browning

To demonstrate that two natural products obtained with minimal processing can be used as antibrowning agents, extracts of dog rose hips and pomegranate arils were assayed for inhibition of tyrosinase and polyphenol oxidase activity. The efficiency of antibrowning activity was evaluated in terms of absorbance and polyacrylamide gel zymograms. In addition to the in vitro studies, melanosis in foods such as artichokes, mushrooms and pear juice was evaluated. The results revealed that dog rose hip extract was more effective than pomegranate aril extract. Moreover, high performance liquid chromatography analysis showed that extracts from both sources had many potential inhibitors of polyphenol oxidase and tyrosinase activity. (C) 2011 Elsevier Ltd. All rights reserved.