caa a22 4500 606243526 CHVBK 20210128101325.0 cr unu---uuuuu 210128e20151201xx s 000 0 eng 10.1007/s11694-015-9265-0 doi (NATIONALLICENCE)springer-10.1007/s11694-015-9265-0 Physicochemical characteristics and oxidative stability of de-acidified lampante high acid olive oil [Elektronische Daten] [Mohamed Hassanien, Mahmoud Dohim, Ahmed Abdel-Salam, Mahmoud Sitohhy] The aim of this investigation was to enhance the quality of high free fatty acid olive oil (HFFAO). Silica gel (SG) was used as adsorbent by applying filtration and stirring techniques. Alkali treatments with NaOH and Ca(OH)2 were also conducted to neutralize high acidity of HFFAO. The levels of linoleic acid (C18:2) in neutralized oils were lower than in reference olive oil. Untreated and treated HFFAO samples were stored under oxidative conditions for 30days at 60°C. The progress of oxidation was followed by measuring acid value (AV), the formation of oxidative products [i.e., peroxide value (PV) and p-anisidine value (AnV)], total phenolic compounds (TPC), radical scavenging activity toward 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and inhibition of β-carotene in a linoleate model system. The results indicated that SG and alkali treatments were effective in reducing the acidity of HFFAO. Alkali treatments reduced the AV of HFFAO, while treatments with SG induced variable degrees of reduction in HFFAO acidity. The percentage of reduction in the PV for HFFAO using SG was in the range of 10.5-47.3%. Filtration with SG had a significant effect on AnV. Levels of TPC were reduced (ca. 70%) with alkali treatments, while treatments with SG resulted in reduction of about 22-48%. After 60min incubation with DPPH, 78% of DPPH radicals were quenched by control sample, while HFFAO treated with SG or alkali were able to quench from 48 to 56%. SG and alkali treatments were not effective in inhibiting the oxidation of linoleic acid and the subsequent bleaching of β-carotene in comparison with control oil. During autoxidation experiments the same trends of results were noted for both control and treated oils. The results stated that SG with permitted high adsorbing capacity reduced free fatty acids levels in HFFAO and the effect was close to that induced with chemical treatments which are used commercially in a large scale to improve oil quality. Springer Science+Business Media New York, 2015 Silica gel nationallicence Alkali treatment nationallicence High acid olive oil nationallicence Free fatty acids nationallicence De-acidification nationallicence Oxidation nationallicence Phenolic compounds nationallicence Hassanien Mohamed Biochemistry Department, Faculty of Agriculture, Zagazig University, 44519, Zagazig, Egypt aut Dohim Mahmoud Biochemistry Department, Faculty of Agriculture, Zagazig University, 44519, Zagazig, Egypt aut Abdel-Salam Ahmed Biochemistry Department, Faculty of Agriculture, Zagazig University, 44519, Zagazig, Egypt aut Sitohhy Mahmoud Biochemistry Department, Faculty of Agriculture, Zagazig University, 44519, Zagazig, Egypt aut Journal of Food Measurement and Characterization Springer US; http://www.springer-ny.com 9/4(2015-12-01), 564-574 2193-4126 9:4<564 2015 9 11694 https://doi.org/10.1007/s11694-015-9265-0 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s11694-015-9265-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Hassanien Mohamed Biochemistry Department, Faculty of Agriculture, Zagazig University, 44519, Zagazig, Egypt aut NATIONALLICENCE 700 1- Dohim Mahmoud Biochemistry Department, Faculty of Agriculture, Zagazig University, 44519, Zagazig, Egypt aut NATIONALLICENCE 700 1- Abdel-Salam Ahmed Biochemistry Department, Faculty of Agriculture, Zagazig University, 44519, Zagazig, Egypt aut NATIONALLICENCE 700 1- Sitohhy Mahmoud Biochemistry Department, Faculty of Agriculture, Zagazig University, 44519, Zagazig, Egypt aut NATIONALLICENCE 773 0- Journal of Food Measurement and Characterization Springer US; http://www.springer-ny.com 9/4(2015-12-01), 564-574 2193-4126 9:4<564 2015 9 11694