Determination of the peroxidative status of branded and unbranded edible oils marketed in Umuahia, Abia State, Nigeria

Abstract

Contaminated edible oil cause many disease conditions. The aim of this study was to determine the peroxidative status of frequently consumed edible oils marketed in Umuahia, Abia State, Nigeria. 100 samples of edible oils from six notable markets were bought and analyzed using acceptable physical, chemical and biochemical parameters. The highest and lowest values obtained are – density: unbranded palm oil (0.95 ± 0.05 g/ml) and branded vegetable oil (0.89 ± 0.03 g/ml); iodine value: branded soya oil (142.26 ± 24.69 g/ml) and unbranded vegetable oil (57.38 ± 14.48 g/ml); peroxide value: branded vegetable oil (4.43 ± 0.87 meqO2/Kg) and unbranded palm oil (3.58 ± 0.95 meqO2/Kg); acid value: unbranded palm oil (40.45 ± 6.62 mgNaOH/g) and branded vegetable oil (0.72 ± 0.22 mgNaOH/g); malondialdehyde value: branded soya oil (0.69 ± 0.58 mg MDA/Kg) and unbranded palm oil (0.36 ± 0.25 mg MDA/Kg); pH: branded soya oil (6.67 ± 0.28) and unbranded palm oil (3.16 ± 2.12); color: unbranded palm oil (0.68 ± 0.04 A) and branded soya oil (0.02 ± 0.01 A). The identified essential fatty acids in branded vegetable oil include eicosatetraenoic acid (1.33 %) and linoleic acid (92.50 %); unbranded vegetable oil include arachidonic acid (85.70 %), while the non-essential fatty acids in branded vegetable oils include oleic acid (73.00 %) and stearic acid (95.80 %); unbranded palm oil include palmitic acid (93.00 %). This study has revealed that unbranded edible oils marketed in Umuahia are highly saturated, adulterated, rancid, not properly refined, and unsafe for consumption.