Citrus sinensis seed as a potential source of quality edible and industrial oil

Abstract

Seeds of sweet oranges (Citrus sinensis) were analyzed for oil and fatty acid composition. The crude oil was extracted by the use of soxhlet extraction. The results showed that oil content is as high as 71 %. The physico-chemical assessment gave the following results: refractive index (1.457), peroxide value (4.12 meq/kg) and iodine value (34.06 Wijs). The ATR-IR spectrum of oil showed prominent bands at 3008.6, 2921.73, 2852.7, 1742.86, 1709.23, 1460, 1167.66, 1117.39 and 1051.16 cm-1 that identified fatty acid composition. The percentage compositions of various classes of fatty acids present in the oil were polyunsaturated fatty acids (PUFAs, 39.82 %), monounsaturated fatty acids (MUFAs, 57.08 %) and saturated fatty acids (SFAs, 3.09 %). The oil has linoleic acid (18:2, n-6) as the only PUFA and the second highest fatty acid composition (25.63 %). Palmitoleic acid is the highest MUFA (56.30 %) as well as the highest fatty acid composition while capric acid (C10:0) is the lowest fatty acid (0.02 %). These results and in addition to the low compositions of erucic acid, behenic acid and lignoceric acid indicated that the seed oil of sweet orange is possible suitable for both human consumption and industrial purposes