Physico-Chemical Characteristics and Level of Some Selected Metal in Edible Oils

Abstract

The physico-chemical properties and level of some essential metals of four edible oils, two imported (Viking and Avena) and two processed in Ethiopia (Selam and Nur) oil samples, were analyzed using classical wet chemical method and flame atomic absorption spectroscopy techniques, respectively. The result of physico-chemical properties shows that acid value in Avena and Viking oils which is 0.091±0.0042 mgKOH/g and 0.082±0.0047 mgKOH/g, respectively, from palm oil variety and in Selam and Nur oils 0.276±0.0056 mgKOH/g and 0.188±0.0050 mgKOH/g, respectively, from noug oil variety, saponification value in Avena and Viking oils which is 190.27±3.528 mgKOH/g and 189.80±3.528 mgKOH/g, respectively, and in Selam and Nur oils 187.00±5.668 mgKOH/g and 143.05±8.527 mgKOH/g, respectively, iodine value in Viking and Avena oils which is 97.545±0.6345 g and 53.807±1.0150 g, respectively, and Nur and Selam oils 116.410±0.3863 g and 88.153±0.5300 g, respectively, and peroxide value in Viking and Avena oils which is 1.413±0.0808 meq/kg and 1.233±0.0305 meq/kg, respectively, from palm oil variety and in Selam and Nur oils 0.893±0.0503 meq/kg and 1.460±0.0600 meq/kg, respectively, from noug oil variety were obtained. The level of essential metals in edible oil samples was analyzed after wet digestion. The results show that levels of Cu in Viking and Avena oils that were 0.62±0.022 mg and 0.28±0.004 mg, respectively, and in Selam and Nur oils 0.86±0.003 mg and 0.42±0.005 mg, respectively, and the levels of Zn in Viking and Avena oils that were 1.58±0.154 mg and 1.27±0.255 mg, respectively, and in Selam and Nur oils 1.19±0.160 mg and 1.47±0.567 mg, respectively, were obtained. The physico-chemical properties and level of essential metal revealed that four edible oils were acceptable to human consumption.