Lesser known Nigerian edible oils and fats II.—Ito seed oil

The seeds of Cucumeropsis edulis (Hook, f.) Cogn., family Cucurbitaceae, are a common component of the average Nigerian diet and a rich source of oil. This study shows the oil to be very suitable for edible purposes, since it possesses good keeping qualities, and has a high content of linoleic and oleic acids, which together make up about 64% of its total fatty acid content. the main characteristics of the oil are described.     

Lesser known Nigerian edible oils and fats. I.—Characteristics of melon seed oils

Some of the characteristics of a melon seed oil, which is shown to be of the semi-drying type containing mainly linoleic and oleic acids, are described.     

Lesser known Nigerian edible oils and fats. 3. Fatty acid compositions as determined by gas-liquid chromatography

The seeds of Parkia filicoidea, Treculia africana, Mucuna flagellipes, Telfairia occidentalis, Citrullus lanatus and Cucumeropsis edulis are commonly used in Nigerian cooking. The component acids of the oils of these seeds have been investigated qualitatively and quantitatively by gas-liquid chromatography. Some of the seeds are shown to be a rich source of oil.     

The Nigerian diets: Distribution of protein,carbohydrate, fat,fibre and minerals

Nigerian diets consumed by population groups in the Calabar Metropolis were analysed for protein, carbohydrate, fat, fibre and mineral constituents. The crude protein content ranged between 5·4% and 26·3% (dry weight), 9·5% and 24·4% and 7·2% and 25·5% for breakfast, lunch and dinner diets, respectively. The ranges of values for carbohydrate, crude fat, crude fibre and total cholesterol were 32–83%, 9–39%, 1·3–3·9% and 54·8–1046 mg (per 100 g dry weight) respectively, for breakfasts; 43–75%, 12–30%, 1·8–3·4% and 452–900 mg, respectively, for lunch diets and 47–78%, 11–28%, 1·5–3·5% and 98·5–863 mg, respectively, for dinners. Typical Nigerian diets provided 25% of total food energy from fat. The mineral analysis provided data on twelve minerals and their distribution in the diets.The results indicate that diets consumed in the Calabar Metropolis contain moderate protein, low fat and cholesterol, high carbohydrate and dietary fibre, but the diets of elite groups approximate those of western nations in composition.     

Intramuscular fatty acid composition of lambs fed diets containing alternative protein sources

Thirty male Merinizzata italiana lambs were divided into three groups after weaning according to live weight. The diet of the three groups differed in the main protein source used in the concentrate, soybean meal for treatment SBM, faba bean for treatment FB and peas for treatment PEA. Lambs were fed ad libitum and slaughtered at about 160 days of age. Meat from the PEA group had higher proportions of the essential fatty acids C18:2 ω-6 and C18:3 ω-3 than from FB and SBM lambs and consequently its derivatives, C20:4 ω-6 and C20:5 ω-3 respectively, were higher in meat from PEA animals, compared to SBM and FB ones. The total n-3 fatty acids were highest in meat from PEA lambs and consequently PEA lambs showed a more favourable n-6/n-3 ratio. In conclusion the use of legume seeds such as peas in lamb diets positively affected intramuscular fatty acid composition.     

Saponin content of some Nigerian foods

Saponins have been extracted and purified from millet (Pennisetum typhoideum), beans (Phaseolus vulgaris), guinea-corn (Sorghum vulgare) and groundnut (Arachis hypogaea). Beans were found to contain a considerable amount of saponin—245.0 mg kg^?1, while millet, guinea-corn and groundnut contained 194.7, 72.7 and 48.8 mg kg^?1 dry weight basis respectively.     

Protein quality of some Nigerian feedstuffs. II. Biological evaluation of protein quality

The protein quality of some Nigerian protein concentrates were studied by conventional protein quality techniques using weanling albino rats of the Wistar Strain. The true digestibility of the concentrates were between 90 and 98% for most of the feedstuffs examined, except the cashew nut scrap kernel meals I and II, (84.6 and 84.3%); the African locust bean seed only (75.9%); the African locust bean seed and pulp (81.6%); and the palm kernel meal (74.2%) which showed significantly lower values than the others. The animal protein sources examined (milk powder, casein, fishmeals and egg) were found to show superior p.e.r., n.p.r., p.r.e., n.p.u. and b.v. values to those observed for the cashew nut samples, African locust bean seed, groundnut and palm kernel meal. Blood meal, however, could not support the growth of rats and showed poor protein quality indices: ?2.46, 0.83, 16.1, 18.9 and 19.3 for the p.e.r., n.p.r., p.r.e., n.p.u. and b.v., respectively. The cashew nut scrap kernel meal samples I and II with protein values in the range 0.76 to 1.12, 2.86 to 3.13, 45.7 to 50.1, 41.3 to 46.7 and 48.9 to 55.3 for p.e.r. n.p.r., p.r.e., n.p.u. and b.v., respectively, were poorer compared to the good grade kernel meal with values of 2.01, 4.01, 64.2, 63.0 and 68.6 for p.e.r., n.p.r., p.r.e., n.p.u. and b.v., respectively, probably as a result of more severe heat damage. The African locust bean seed samples could not support the growth of rats, gave negative p.e.r. (?3.19 to ?2.54); low n.p.u. and b.v. (19.8 to 20.9 and 22.3 to 23.7). The palm kernel meal, despite its apparent balance of amino acids showed poor protein quality indices: 1.27, 2.62, 42.0, 44.1 and 56.7 for p.e.r., n.p.r., p.r.e., n.p.u. and b.v., respectively, attributable to its high fibre content and a concomitant lowering of the digestibility.     

Nutritional evaluation of some Nigerian wild seeds

Some wild seeds, namely Parkia biglobosa, Tetracarpidum conophorum, Pentaclethra macrophylla, Irvingia gabonensis, Afzelia africana, Prosporis africana and Monodora myristica, were randomly collected from various parts of Nigeria and analyzed with regard to their proximate, mineral, antinutrient composition and zinc bioavailability. The results revealed that the seeds had high protein (6.5-24.2%), fat (19.0-58.5%), mineral (Mg, Fe, Zn, Mn, Ca, Na, K, P) and phytate (1043.6-2905.2 mg/100 g) contents, while the cyanide content was low (3.7-6.4 mg/kg). However, Co, Pb and Ni were not detected in all the samples. The calculated [Ca] [phytate]/[Zn] molar ratios (which is the best index for predicting Zn bioavailability) for all the seeds revealed that Parkia biglobosa, Irvingia gabonensis and Prosporis africana had a calculated molar ratio above 0.50 mol/kg (critical level), thus indicating reduced bioavailability of Zn to a critical level. In view of the high fat, protein, mineral and low cyanide contents, the high phytate content would not be expected to reduce bioavailability of Zn in some of the wild seeds (Afzelia africana, Pentaclethra macrophylla and Monodora myristica). These wild seeds could be good nutrient sources if integrated fully into human and animal nutrition. However, further studies will be carried out on the protein quality and toxicological potentials of these wild seeds.     

Alternative protein sources in Western diets: Food product development and consumer acceptance of spirulina-filled pasta

Spirulina (Arthrospira platensis) is currently being increasingly researched for its usability and suitability in human nutrition. The inclusion of alternative protein sources, such as spirulina, in familiar products is a possible strategy to nudge consumers towards dietary change in Western societies. Filled pasta variants with three levels of spirulina-soy-extrudate in the filling (10%, 30% or 50%) were developed and investigated for their sensory characteristics and consumer liking. Recipe development was based on the concepts of flavor-flavor learning (beet-ginger or tomato) and masking (lemon-basil) to account for the musty and earthy notes of the alga. Consumer tests were conducted in Germany (n = 139), the Netherlands (n = 137) and France (n = 144), and conventional sensory profiling was accomplished with trained panelists (n = 12). Consumers preferred the lemon-basil flavor over tomato and beet-ginger flavored fillings. As expected, liking decreased with increased extrudate content, regardless of the flavor. For all flavors expected liking was higher than liking after product exposure; for the lemon-basil flavor the gap was the smallest. It was shown that low general food neophobia and familiarity with spirulina promoted consumer liking. The sensory profiling revealed that the spirulina-soy-extrudate content affected all sensory attributes identified across all flavors, but for the tomato flavor the most. Overall, this study confirms that it is important to consider differences in consumer motivation as well as the product’s conceptual and intrinsic sensory characteristics in new product development.     

Nutritive value of some Nigerian edible mushrooms

Samples of Termitomyces robustus, T. clypeatus and Pleurotus tuber-regium were analysed for their nutrient and toxic substances. The Termitomyces spp. contained as much as 31% proteins and about 32% carbohydrates, of which at least 26% were reducing sugars. Pleurotus tuber-regium contained 14·6% protein and 18·6% carbohydrates, of which only about 2·9% were reducing sugars. There was little difference in their crude fibre and ash content, while the fat content of T. robustus was a little higher than those of the other samples. The ascorbic acid content of each of the Termitomyces spp. (10 mg% and 14·3 mg%) was much higher than that of Pleurotus sp. (3·3 mg%). All the mushroom samples were low in hydrocyanic acid (HCN) and oxalate contents.     

Effect of tannic acid on in vitro enzymatic hydrolysis of some protein sources

The pH‐stat system has been used to assess the effect of tannic acid (TA) on solubility and in vitro enzyme hydrolysis of different proteins. Added TA (from 10 to 50 g kg^?1) decreased the extent of hydrolysis of bovine serum albumin. Enzymic hydrolysis of casein, pea meal, soybean meal, and haemoglobin (HB) was increased, as measured by total amino acids released and by the degree of hydrolysis. SDS‐PAGE confirmed the results of the in vitro enzymatic hydrolysis. These findings suggest that, under in vitro conditions, when simulating the gastrointestinal environment of domestic mammals, the negative effects of TA described from in vivo experiments are not necessarily due to reduced hydrolysis of proteins. Copyright © 2003 Society of Chemical Industry     

Composition of some recommended Nigerian commercial cottonseed varieties

Three Nigerian commercial cottonseed varieties, Samaru 71 (S71), Samaru 72 (S72) and Samaru 77 (S77), and composite cottonseed from three locations, Funtua (CSF), Mallumfashi (CSM) and Kano (CSK) were assayed for proximate, mineral and amino acid composition. Crude protein averaged 37·4% for the varieties and 36·2% for the composite seed. The oil content ranged from 33·6% to 35·1% for the varieties, and averaged 32·7% in the composite seed. Crude fibre, ash and nitrogen-free extracts did not vary between or within seed type. The mineral levels were relatively high, and phosphorus was the most abundant, averaging 1·34% and 1·28% in the varieties and composite seed, respectively. The mineral levels were generally lowest for S72 and CSM within their respective seed categories. Amino acid levels obtained for both cottonseed types were higher than, or comparable with, those reported by other workers for cottonseed elsewhere. Amino acid levels were, in general, lower in composite seed than in the seed varieties. Varietal and locational factors appeared to influence the chemical components in cottonseed.     

Moisture sorption isotherms of some Nigerian food grains

A fluidized bed apparatus that can be used to determine moisture sorption isotherms of granular food products is described. This apparatus was used to obtain moisture sorption isotherms for maize, cowpeas, groundnuts and soyabeans at temperatures of 30, 40 and 50°C. Hysteresis was observed in the isotherms for the four products and the equilibrium moisture content was lower for the oily grains (soyabeans and groundnuts) at the same value of relative humidity. The Hailwood and Horrobin equation was used to correlate the experimental data and the values of the correlating constants are tabulated. The Brunauer, Emmett and Teller equation was also used to obtain estimates of the monolayer water content for the four grains.     

Trypsin inhibitors in some lesser known seeds in Nigeria

Trypsin inhibitors (TIs) were extracted and determined spectrophotometrically from seed meals of African breadfruit (Treculia africana), African walnuts (Coula edulis Bail), Calabash (Lagenaria sicerania) and Castor (Ricinus communis). The TI activities were for Castor 1319 × 10⁻⁴, African breadfruit 620 × 10⁻⁴, and Calabash 28·4 × 10⁻⁴ and for African walnuts only a trace of TI units per milligram protein of the extract. The total protein content and in vitro protein digestibility for the four seed meals were also determined and observed to be quite high for Calabash seeds.     

Levels of some trace elements in hospital diets

Composite diets served to patients at the University College Hospital, Ibadan were collected and analysed for their concentration of zinc, copper, iron, manganese and cadmium. Data collected indicate that the concentration of zinc for breakfast foods was highest in bread and fried egg and lowest in bread alone. Copper was highest in yam and corned beef stew but not detected in any of the bread-containing breakfast foods. Iron and manganese were highest in hot pap and moinmoin and lowest in yam, stew and meat.For lunch and dinner diets, the concentration of zinc was highest in dodo, stew and meat and lowest in dodo alone; copper was highest in eba, melon soup and meat and was non-detectable in jollof rice and meat, pounded yam, melon soup and meat. Iron was highest in amala, melon soup and meat and lowest in dodo alone. Manganese was highest in agidi, vegetable soup and fish and was non-detectable in pounded yam, okro soup and fish. The levels found appear sufficient to meet daily dietary requirements.     

Effect of transglutaminase on some properties of cake enriched with various protein sources

ABSTRACT:  The effect of transglutaminase (TG) enzyme addition (0% and 0.09%) on batter and cake properties, prepared with different protein sources (nonfat dry milk [NFDM], soy flour, and soymilk) and flour types (type A with 11.4% protein and type B with 8.6% protein), was investigated. Specific gravity and pH of cake batters were determined, and physical and chemical analysis of the cake samples was performed. Soy products improved cake weight, volume, softness, protein, and fat contents. NFDM increased the crust redness and crumb lightness more than the other protein sources. TG enzyme addition affected the volume, softness, crust, and crumb color of the cake samples significantly ( P < 0.05). The combination of TG enzyme and flour B with lower protein gave more puffed, symmetrical, and softer cake samples. TG had a potential application with different protein sources in cake production. Especially interactions between TG with soy flour and TG and wheat flour with high protein content were important in cake formulations due to the softening effect on crumb.     

Ileal amino acid digestibility of some novel dietary protein sources for growing chickens

The apparent ileal digestibility coefficients of amino acids in five high‐protein ingredients (casein, isolated soyprotein, maize gluten meal, spray‐dried bovine plasma (SBP) and spray‐dried porcine plasma (SPP)) and soybean meal were determined using 3‐week‐old broiler chickens. The amino acids in casein were highly digestible. Isolated soyprotein was also well digested by the birds, but the digestibility coefficients of all amino acids in isolated soyprotein were lower (P < 0.05) than those in casein. The amino acid digestibility coefficients in isolated soyprotein were greater (P < 0.05) than those in soybean meal, which may be reflective of reduced concentrations of anti‐nutritive factors, particularly indigestible oligosaccharides. The digestibilities of amino acids in maize gluten meal were higher (P < 0.05) than those in soybean meal, except for the digestibilities of arginine, histidine, threonine and aspartic acid, which were similar (P > 0.05) between the two protein sources. The ileal digestibilities of all indispensable amino acids in SBP and SPP were lower (P < 0.05) than those in casein and isolated soybean meal but higher (P < 0.05) than those in soybean meal. No differences (P > 0.05) were observed in the digestibility of amino acids between SBP and SPP. The overall mean amino acid digestibility coefficients of casein, isolated soyprotein, soybean meal, maize gluten meal, SBP and SPP were 0.955, 0.888, 0.823, 0.849, 0.860 and 0.856 respectively. Copyright © 2006 Society of Chemical Industry