African Journal of Biotechnology Vol. 5 (11), pp. 1095-1101, 2 June 2006   

ISSN 1684–5315 © 2006 Academic Journals        

Full Length Research Paper

Extraction, chemical composition and nutrional characterization of vegetable oils: Case of Amaranthus hybridus (var 1 and 2) of Congo Brazzaville

J. R. Dhellot¹*, E. Matouba^1,2, M.G. Maloumbi¹, J.M Nzikou^1,2, D.G. Safou Ngoma¹_,  M. Linder², S. Desobry² and M. Parmentier²

¹ENSP – Laboratoire de Valorisation des Agro ressources (LVAR) BP 69 Brazzaville, CONGO.

²ENSAIA – Laboratoire de Physico-chimie et Génie Alimentaires 2, avenue de la forêt de Haye, 54505 Vandoeuvre-lès-Nancy

*Corresponding author. E-mail: dhellotjoce@yahoo.fr; Tel.: +2425560450.

Abbreviations: DHA, docosa hexaenoic acid; DSC, differential scanning calorimetry; FAME, fatty acid methyl ester; IV, iodine value; L, linoleic acid; Ln, linolenic acid; O, oleic acid; P, palmitic acid; PUFA, poly unsaturated fatty acid; PV, peroxide value; S, stearic acid; SFA, saturated fatty acid; SV, saponification value; TAG, triacylglycerol; and UFA, unsaturated fatty acid.

Accepted 5 May, 2006

Amaranthus hybridus is a vegetable which is eaten in Congo Brazzaville and in other countries.  Two varieties of A. hybridus seeds (var 1 and 2) were selected for this study. Average oil content varies between 11 and 14%. A. hybridus seeds are also rich in proteins (17%) and minerals. Red oils obtained have a high saponification value (130-190) and the iodine value is between 100 and 113. The quantity of unsaponifiable matter (5 - 7%) in these oils is important. The fatty acids composition gives the following average profile: 18: 2n-6 > 18: 1 n-9 > 16: 0 > 22: 6n-3 > 18: 0. A. hybridus seeds oils also have long chain poly unsaturated fatty acids such as DHA (5.63-21.46%) and the results indicated that the n−6/n−3 ratios were 1.48 to 5.63. The triacylglycerols analysis shows that oils extracted by Bligh and Dyer method contains 6 major TAGs in A. hybridus var1: LLnLn › OLL › POL. › OLL › PLL › LLL and Amaranthus hybridus var2: LLnLn › OLL › PLL › POL. › OLL › LLL. The A. hybridus seeds can be used as cattle food and baby complement food. These oils have nutritive and dietetic potentialities.

Key words: Amaranthus hybridus oil, Congo Brazzaville, TAG, chemical methods extraction.