Abstract

STABILIZATION OF EDIBLE OIL BY ONION PEEL AND RATAN JOT EXTRACT ON STORAGE TO PREVENT HUMAN HEALTH HAZARD

Lubna Mobin*, Syed Asad Sayeed, Rashida Ali, M. Abdul Haq, Dr. Zaid Pirzada and DR. S.M. Ghufran

Abstract

Edible oil can be oxidatively stabilized using natural phenolic extracts. The oxidation of oil eliminates health benefits of edible oil. They produces reactive species in it that cause many human health hazard. The phenols ring structure defines its antioxidant activity in oil medium. Onion peel and ratan jot have been reported to contain the phenols of different nature (or structure). This study aims to delay oxidation in edible oil on storage by adding aqueous methanolic extract of onion peel and ratan jot in it. Total phenolic content (TPC) as determined by Folic-Ciocalteu method in onion peel was found to be 48.02 and 33.64 gm of gallic acid per kg in ratan jot extract. Antioxidant capacity (AC) as determined by DPPH radical scavenging activity method was found to be 87 % in onion peel extract and 55 % in ratan jot extract. The extracts were added in three different concentrations (300, 600 and 900 mg/kg) to preheated edible (sunflower) oil. Treated and untreated (control) oil samples were then stored in dark at ambient temperature (approx. 360C) for eighty days. The samples were then analyzed periodically with an interval of ten days for lipid oxidation parameters, peroxide value (PV), free fatty acid (FFA) and para anisidine value (P-AV). Both extracts showed dose dependent antioxidant activity and were effective in preventing formation of hazardous compound in edible oil. However, Onion peel extract due to stabilized the edible oil againts detrimental spoilage for longer period than the ratan jot extract at all the concentrations.

Keywords: Human Health, Plant Phenols, Edible oil, Oxidation, Total Phenolic Content, Antioxidant Capacity