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

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-3ratios 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 ascattle food and baby complement food. These oils have nutritive and dietetic potentialitie

Extraction and nutritional properties of Solanum nigrum L seed oil

With the aim of diversifying the lipids sources eaten by the African populations and those of Congo Brazzaville in particular, a physicochemical study of Solanum nigrum L seeds was carried out and three chemical methods (Soxhlet, Bligh and Dyer, and Folch) were used to extract the oil. The dry matter content of the seeds is 94.22%. Average lipids content varies between 34.5 and 37.5% dry matter, proteins content is 17% dry matter and crude ash content averages 7.18% dry matter and the principal mineral element is Mg (180 mg/100g). The acid value of the oil is about 2.5, saponification value varies between 157.3 and 190.1, peroxide value is low at 5.13 and iodine is 102.33.The fatty acid compositions of S. nigrum seeds oil shows that it has 67.9% of linoleic acid, indicating its high unsaturation. Apart from linoleic acid, other prominent fatty acids were palmitic, stearic and oleic acids. The following average profile is: 18: 2n-6 > 18: 1 n-9 > 16: 0 > 18: 0. The oil is liquid at room temperature and green in colour. Oil viscosity varies between 20 and 35 mPa.s at 25°C. Three activation energies which vary between 0.8 to 26.58 kJ.mol-1 were determined using Arrhenius’s equation. The melting points estimated by Differential Scanning Calorimetry were found to be between -22.0 and -12.0°C for the Soxhlet and Folch-extracted oils. Bligh and Dyer oil have three melting points at -36.2, -15.2 and 33.7°

A study on gumbo seed grown in Congo Brazzaville for its food and industrial applications

Proximate composition, energy content and mineral concentrations of okra seeds grown in two localities of Congo Brazzaville were investigated. The paper also reports the physicochemical characteristics of the oil extracted from the seeds. Ash was highest (5.84±0. 2%) in Dolisie okra seeds (DOS) followed by Brazzaville okra seeds (BOS) with a value of 5.52±0.34%. Protein ranged from 25.48±0.57% in DOS to 23.73±0.35% in BOS. Crude fat content is of 29.31±0.83% for BOS and 25.71±0.44 % for DOS. Totalcarbohydrates were generally high in all the seeds and ranged from 31.84% in BOS to 231.27% in DOS. The seeds were found to be good sources of minerals. Phosphorus (1755.95–1464.87 mg/100 g), magnesium (3895.67–2743.5 mg/100 g) and potassium (124.59-116.05 mg/100 g), were highest in two okra seeds cultivars. The physical properties of the oil extracts showed the state to be liquid at room temperature and the colour to be golden-yellow, in general. Thermal analysis show that fatty acids melting point was lowest ranged between -25°C and +6.55°C. Gas liquid chromatography revealed thatthe major fatty acid was linoleic acid (34.89-44%), palmitic acid (25.2-28.3%) and oleic acid (21.9-24.08%). Abelomschus esculentus seeds oil (AESO) content long chain poly unsaturated acids aseicosapentanoic acid (EPA) and docosahexaenoic acid (DHA) and erucic acid (1.1–4.1%). It can be inferred that the oil seeds investigated are good sources of crude fat, crude protein, ash and minerals. The oil extracts exhibited good physicochemical properties and could be useful as edible oils and for industrial applications