Simulation of Multistage Extraction of Antioxidants from Chilean Hazelnut (Gevuina avellana) Hulls

摘要

The objective of htis study was to analyze the fac-tors affecting the ethanol extraction of Chilean hazelnut (Ge-vuina vaellana) hulls to obtain antioxidant compounds.The ef-fects of temperature on the kinetics of polyphenolica estraction and on the antioxidant activities of the extracts were assessed.The radical-scavenging activities of the extracts were compara-ble with that of BHA when used at the same concentfration .The optimal temperature for the antioxidant activities of the extracts was 40 deg C.A four-stage countercurrent etation was simulted,where each stage lasted 30 min.est reslts were obtained with counterdurrent extraction,which produced an extract that showed 94.4% alpha,alpha-diphenyl-beta-picrylhydazyl radical inhibition,compared with 86.2% obtained in the first stage of cross-flow extraction and 92.32% in a batch extraction that lasted 100 h.UV-vis and NIR specta of extracts from cross-flow and from the simulated countercurrent extraction revealed that the composi-tion of extracts varied along the stages and was affected by the operational strategy.