Proximate composition,amino acid content and haemagglutinating and trypsin‐inhibiting activities of some Brazilian Vigna unguiculata (L) Walp cultivars

Seeds of Brazilian Vigna unguiculata (L) Walp cultivars (EPACE 10, EPACE 11, Pitiuba, TVu 1888, IPA 206 and Olho de Ovelha) were analysed to establish their proximate composition, amino acid content and presence of antinutritional and/or toxic factors. The seed protein, carbohydrate and oil contents ranged from 195 to 261 g kg⁻¹ dry matter, from 678 to 761 g kg⁻¹ dry matter and from 12 to 36 g kg⁻¹ dry matter respectively. EPACE 10, EPACE 11, Pitiuba, TVu 1888, IPA 206 and Olho de Ovelha cultivars are rich in glutamin/glutamic acid, asparagin/aspartic acid and phenylalanine + tyrosine. The essential amino acid profile compared with the FAO/WHO/UNU scoring pattern requirements for different age groups showed that these seeds have methionine + cysteine as the first limiting amino acid for 2–5‐year‐old children. However, only Pitiuba, IPA 206 and Olho de Ovelha are deficient in methionine + cysteine for 10–12‐year‐old children. The contents of threonine, valine, isoleucine, leucine and methionine + cysteine of all cultivars were lower than those of hen egg. Haemagglutinating activity measured against rabbit erythrocytes was found to be present in the six cultivars, but only after the red cells were treated with proteolytic enzymes. All cultivars displayed protease inhibitor activity which varied from about 12.0 to 30.6 g trypsin inhibited per kg flour. Urease and toxic activities were not detected in any of the studied cultivars. © 2000 Society of Chemical Industry     

Diversity in nutritional composition of wild jack bean (Canavalia ensiformis L. DC) seeds collected from south India

Nine accessions of the wild jack bean (Canavalia ensiformis L. DC) seeds collected from nine different locations of south India were analysed for proximate composition and mineral profiles. The major findings of the study were as follows: crude protein ranged from 28.9 to 35.0%, crude lipid 3.4–4.7%, crude fibre 7.0–10.7%, ash 3.0–5.8%, carbohydrates 46.1–54.5% and energy levels 1469–1574 kJ 100 g⁻¹ DM. Significant (P<0.05) diversity was observed in crude protein and carbohydrate contents among the accessions collected from different locations based on analysis of variance (ANOVA) analysis. Potassium was the most abundant mineral, which ranged from 634 mg 100 g⁻¹ in Dasukuppam accession to 1017 mg 100g⁻¹ in Valacode accession. Sodium and magnesium levels are generally low with mean values of 63 and 250 mg 100 g⁻¹, respectively. In the present study, in all minerals, significant diversity was observed among the accessions collected from different locations.     

Chemical composition and nutritional evaluation of an underexploited legume,Acacia nilotica (L.) Del.

Nutritional and antinutritional characteristics and biological value of Acacia nilotica (L.) Del. seeds were investigated. The mature seeds contained 234 g kg⁻¹ crude protein, 126 g kg⁻¹ crude fibre, 66.6 g kg⁻¹ crude fat, 39.7 g kg⁻¹ ash and 534 g kg⁻¹ carbohydrates. Potassium, phosphorus, magnesium, iron and manganese occurred in high concentrations. The essential amino acid profile compared well with the FAO/WHO recommended pattern except for cystine, methionine and threonine. Cystine and methionine were the first limiting amino acids. When compared with the globulin fraction, albumins appeared to be a richer source of cystine, methionine, threonine, lysine and tryptophan. Oleic and linoleic acids constituted the predominant fatty acids (66.9%). Both dry-heating and autoclaving reduced the antinutritional components significantly. The in vitro protein digestibilities of raw, dry heat-treated and autoclaved seeds were 61.2%, 77.4% and 80.2%, respectively. Biological value, true digestibility and net protein utilization were significantly higher in processed seed than in raw seeds. The utilizable protein difference was insignificant between raw and processed seed samples.     

Chemical composition of mature seeds from different cultivars and lines of Vicia faba L.

Whole mature seeds and cotyledons (testa and embryonic axes having been removed) from 30 cultivars or lines of Vicia faba were analysed for their chemical composition. Cultivars and lines showed variation in crude protein (26–38%, cotyledons; 26–39%, whole seeds), starch (41–58%, cotyledons; 35–53%, whole seeds), ethanol-soluble sugars (5–9%, cotyledons; 6–11%, whole seeds), uncombined amino acids (0.73–1.5%, whole seeds) and uncombined arginine (0.34–1.34%, whole seeds). Crude protein and carbohydrate (i.e. starch plus ethanol-soluble sugars) were inversely related. The large-seeded cultivars and lines (above 700 mg fresh weight) had a lower concentration of starch but a higher concentration of ethanol-soluble sugars than small-seeded ones with an equivalent protein concentration. Significant correlations were found between the protein concentration and that of uncombined amino acids and of arginine.     

Physico- Chemical Characteristics and Functional Properties of Starch and Dietary Fibre in Grass Pea Seeds

Physico-chemical and functional properties of starch and fibre in raw and processed grass pea seeds were evaluated. Whole grass pea seeds were found to contain 41 % starch and 17% total dietary fibre (2% soluble and 15% insoluble) on dry matter basis. Examination by using scanning electron microscopy revealed oval shaped starch granules with an average width of 17 μm and length of 25 μm. Raw sample had a gelatinization onset temperature of 62°C and two endothermic transition peaks at about 73°C and 94°C, in addition the starch isolated from grass pea flour was shown to have a transition enthalpy (ΔH) of 10 Jg⁻¹. The viscosity of the raw sample (using a Brabender amylograph) reached peak maximum at 80–95°C, decreasing during the 30 min holding time (at 95°C) followed by an increase during cooling to 50°C. Raw whole seed flour was shown to have a water absorption and water solubility index (WSI) of 3 and 16%, respectively. Samples that had been cooked for 60 min had a lower WSI than those cooked for 30 min; this was further reduced in the samples cooked after soaking. The carbohydrate extracted from raw flour was found to be mainly high Mwt carbohydrate (55%), eluted at Kav < 0.2.     

Effect of processing on the content of β-N-oxalyl-α, β-diaminopropionic acid (gb-ODAP) in grass pea (Lathyrus sativus) seeds and flour as determined by flow injection analysis

The effect of cooking, roasting, autoclaving and fermentation on the content of β-ODAP in the whole seeds and flour of grass pea (Lathyrus sativus) were studied at different levels of temperature, time, pH, degree of soaking and moisture content. The method of determination used was flow injection analysis, with immobilised glutamate oxidase and horseradish peroxidase. The whole seeds flour was found to contain about 922 mg 100g⁻¹ β-ODAP in dry weight basis. The reduction of β-ODAP content, in samples which were cooked for 60min and roasted (150 °C for 60min) was 57% and 82%, respectively. The content of β-ODAP in dry seeds autoclaved for 30 min also showed a significant (p = 0.05) reduction by 39%, as compared to that of raw whole seeds. Similarly, by cooking of presoaked seeds the content of β-ODAP was reduced by up to 67%. Neither the back-slopped fermentation process nor the spontaneous fermentation were effective in reducing the content of β-ODAP. Whereas roasting and autoclaving of the milled samples caused significant (p = 0.05) reduction in the content of β-ODAP up to 30% and 50%, respectively, compared to that of raw whole seeds.     

Characterisation of peptides in silages made from perennial ryegrass with different silage additives

The effects of applying either formic acid (5.4 g kg⁻¹), a mixture of formic acid (2.7 g kg⁻¹) and formaldehyde (1.5 g kg⁻¹, 81 g kg⁻¹ herbage crude protein) or two concentrations of a cysteine peptidase inhibitor, cystamine (5 or 50 g kg⁻¹), to perennial ryegrass (Lolium perenne) on the nitrogen (N) distribution of the resulting silages were investigated, with emphasis on changes in concentration, composition and molecular weight of silage peptides. Herbage (156 g dry matter kg⁻¹ and 141 g water‐soluble carbohydrate kg⁻¹ dry matter) was ensiled in triplicate in laboratory silos for 100 days. Formic acid and the formic acid/formaldehyde mixture reduced soluble non‐protein N and ammonia N concentrations (P < 0.01); in addition, formic acid increased peptide N concentrations (P < 0.05). Cystamine at 50 g kg⁻¹ reduced ammonia N concentrations (P < 0.01) and increased peptide N concentrations (P < 0.05), but when applied at 5 g kg⁻¹ had little effect. Gel filtration of silage extracts on Sephadex G‐25 suggested that a small proportion (0.06–0.11 g kg⁻¹ peptide N) of silage peptides had a chain length of 7–9 amino acids, but remaining peptides were smaller with chain lengths of 2–6 amino acid residues. Amino acid analysis of silage peptides indicated that additive treatment had little effect on peptide amino acid composition but that peptides with a chain length of 7–9 amino acids contained lower proportions of isoleucine and arginine. © 2000 Society of Chemical Industry     

Nutritive value of a mixture of tigernut tubers (Cyperus esculentus L.) and baobab seeds (Adansonia digitata L.)

The seeds of baobab (Adansonia digitata L.) and the tubers of tigernut (Cyperus esculentus L.) were analysed chemically for their proximate composition and amino acids. The tubers contained 47.9% digestible carbohydrates, 32.8% oil and 3.8% crude protein. The baobab seeds contained 24.1% digestible carbohydrate, 29.7% oil and 28.4% crude protein. A mixture of the vegetables was prepared from three parts of the tigernuts and one part of baobab seeds, by weight, such that a 10% crude protein meal was obtained. The chemical score of the mixed vegetable was 51%, based on limiting amino acids, i.e. those which contain sulphur. The level of antinutritive substances, such as tannin and tryptic inhibitors, in the raw vegetables were reduced by soaking or boiling.     

Non-structural carbohydrate partitioning in Phaseolus vulgaris after vegetative growth

This study provides information on the concentration and quantity of starch, reducing sugars, total sugars, and non-reducing oligosaccharides in the organs of the common bean plant (Phaseolus vulgarisL cv Jamapa) during growth. The following observations were made: (1) the root, stems and branches were temporary carbohydrate storage organs; (2) until 80 days after sowing (DAS), the leaves were the major contributors to the non-structural carbohydrates of the whole plant; (3) during the developmental period studied, non-structural carbohydrate content in the rachis and pulvinus changed frequently; (4) the pod walls contained between 5 and 8% of total sugars at 72 DAS and by maturity soluble sugars diminished to less than 1%; (5) during seed growth (until 80 DAS), the pod walls contained between 11 and 18% starch (dry weight basis) and by maturity this carbohydrate had decreased to 2% of dry weight; and (6) starch represented the major non-structural storage carbohydrate in mature seeds (29%), as opposed to soluble sugars, which amounted to 2·3% of the dry weight.     

Effect of cultivar and seed maturity on amino acid content in fresh and canned broad bean (Vicia faba v. major)

The content of dry matter, total nitrogen, and amino acids (except for tryptophan) in fresh and canned broad bean (Vica fabav. major) seedswas determined, in the canned product whole seeds or cotyledons without hull being analysed. Two Dutch bred cultivars, Comprimo RS with large seeds and medium sized Threefoldwhite, were investigated at four stages of maturity defined by the content of dry matter at levels of about 25% (stage I), 30% (II), 35% (III), and 40% (IV). Amino acid content in 100 g fresh weight was similar in the two cultivars, rapidly increasing with maturation. The value of protein expressed by the EAA index was almost the same for the investigated cvs, usually being slightly higher in the case of more mature seeds. Whole seeds from canned product contained slightly less amino acids than the raw material while the EAA index showed similar or slightly lower values for whole seeds than for the raw vegetable. The content of all the amino acids (except for tyrosine) was greater and the EAA indices were higher in the cotyledons of canned broad bean than in whole seeds. Methionine with cystine were the limiting amino acids in fresh and canned seeds.     

An evaluation of protein quality of fenugreek seeds (Trigonella foenumgraecum) and their supplementary effects

The chemical composition and the nutritional value of protein of whole as well as solvent-extracted fenugreek seeds were determined. Fenugreek seeds are rich in protein (25·5%), fat (7·9%), unavailable carbohydrate (48%), mucilaginous matter (20%) and saponins (4·8%). The replacement of casein diet up to 10% by fenugreek seeds (extracted) did not produce any deleterious effect on protein quality of casein as assessed by protein efficiency ratio (PER), protein and dry matter digestibilities and net protein utilization (NPU). Further increasing the level of fenugreek did reduce these parameters. The extraction of seeds improved, and cooking did not alter the quality of fenugreek seed protein.     

Content of amino acids in fresh and frozen and cooked broad bean seeds (Vicia faba var major) depending on cultivar and degree of maturity

In broad been seeds (cultivars Comprimo RS and Threefoldwhite) harvested at four stages of maturity, which corresponded to dry matter content at the levels of I—25%, II—30%, III—35% and IV—40%, the content of amino acids was determined (g 16 g N⁻¹). The determinations concerned raw broad bean and frozen products cooked for consumption. The content of total and essential amino acids was similar in the two cultivars. With increasing maturity the content of total amino acids and essential amino acids varied, showing a tendency to increase between maturity stages I and IV in all the amino acids, except aspartic acid and alanine in Threefoldwhite. In both cultivars the content of cystine and glutamic acid showed the most rapid rise. Compared with raw broad beans, intact seeds cooked for consumption contained more total amino acids. In products of Comprimo RS the total content of amino acids and essential amino acids was similar in intact seeds and in the dehulled seeds. In products from Threefoldwhite the content of total amino acids and essential amino acids was higher in intact seeds than in dehulled seeds except in the most mature sample where these values were similar. The limiting amino acids were methionine with cystine in both raw broad bean and cooked seeds. © 1999 Society of Chemical Industry     

Non-volatile flavour components of Ganoderma tsugae

Ganoderma tsugae Murrill are currently popular and used in the formulation of nutraceuticals and as functional foods. The non-volatile components in the form of mature and baby fruit bodies (Ling chih), mycelia and fermentation filtrate from submerged culture were studied. Mycelia and filtrate contained significantly higher moisture contents (10.3% and 19.8%) and higher contents of carbohydrates, reducing sugars, crude ash and crude protein. Four forms of G. tsugae contained from 7.65% to 10.1% dry weight of total soluble sugars and polyols. Total free amino acid contents ranged from 2.50 to 149 mg g⁻¹ dry weight and in the descending order of filtrate, mycelia, baby Ling chih and Ling chih. Contents of monosodium glutamate-like components ranged from 0.16 to 26.0 mg g⁻¹ whereas, contents of sweet components ranged from 0.50 to 24.6 mg g⁻¹. The bitter components were predominant. Contents of total and flavour 5^′-nucleotides were high in filtrate (5.48 and 3.10 mg g⁻¹, respectively). The umami intensities were expected to be in the descending order of filtrate, mycelia, baby Ling chih and Ling chih.     

Effect of maturation on nutrient composition of selected vegetable legumes

Five legume vegetables harvested at the immature green and mature stages were analysed for weight and nutrient composition. In some types the seed weight increased up to seven-fold in the last 10 days of maturation. The protein, fat, carbohydrate and thiamin contents increased on maturation. However, the proportional increase varied widely from 10 to 100 % in the case of protein and carbohydrates. The changes observed in the nutrient composition and weight of vegetable legume seeds in the last 10 days of maturation suggest that it is advantageous to harvest vegetable legumes when mature.     

Composition and nutritive value of cormels of Colocasia esculenta (L.) Schott

The nutritional quality of the cormels of Colocasia esculenta (L.) Schott cultivar ‘Guavir’ was determined chemically and biologically in feeding experiments with weanling rats. The contents of starch and unavailable carbohydrates (cellulose, hemicellulose and pectin) were 54 and 15% of the dry matter respectively. Lipid accounted for less than 1% of the dry matter. Palmitic, oleic and linoleic acids were the main fatty acids in the lipids, with linoleic acid predominating. The content and fatty acid composition of the individual lipids was examined. Crude protein amounted to 10.4% of the dry matter. This protein was low in the sulphurcontaining amino acids and tryptophan, but contained adequate levels of the other essential amino acids. Diets containing raw cormel meal gave severely depressed net protein utilisation (NPU) and total nitrogen and carbohydrate digestibility when fed ad libitum to weanling rats. Both NPU and nitrogen and carbohydrate digestibility improved when the cormel meal was cooked prior to inclusion in the diets but such diets still did not support growth in weanling rats.     

Changes in the non-structural carbohydrates associated with the field drying of oat forage

Two trials were conducted to determine the sugars, fructans and starch in oat plants (Avena sativa L) and the changes occurring in these carbohydrate fractions during field drying in the haymaking process. The composition of oat herbage in non-structural carbohydrates varied markedly between years; the contents of sugars, fractals and starch in both leaf blade and non-leaf blade materials being nether in 1990–1991 than in 1991–1992. Field drying produced a significant decrease (P < 0.05) in the amount of soluble carbohydrates. For the whole aerial plant parts, the decline in the fructans concentration ranged between 42.8 and 38.2% and that of sugars between 16.5 and 5.8%. The total losses of sugars and fractions in hay, expressed as losses of dry matter, ranged from 88 to 63 g kg^?1 depending on the year.     

Some nutritional and anti-nutritional characteristics of para-rubber (Hevea brasiliensis) seeds

Para-rubber (Hevea brasiliensis) seeds were examined for their proximate analysis, detergent fibre, amino acid and mineral composition. The seeds were further analysed for the presence of anti-trypsin activity, cyanide, phytate and tannins.The average composition of the seed kernel was determined to be (dry matter basis) 21.5% crude protein, 50.2% crude fat, 6.5% crude fibre, 3.6% ash and 18.2% carbohydrates. The amino acid profile, when compared with the NAS/NRC reference protein pattern, revealed deficiencies of lysine, isoleucine and threonine. The seed kernels contained reasonable amounts of trace minerals, but were poor sources of Ca and P.Fresh seed kernel samples contained toxic levels of HCN (164mg/100g dry weight), but most of the cyanide was eliminated by storage and cooking. The relatively high content of phytate P (37.5% of total P) may be expected to further aggravate the problem of low P and to cause severe Ca/P imbalance. No antitryptic activity or tannins could be detected in the samples studied. Because of the presence of an anti-fertility factor and collection and storage problems, it is concluded that rubber seeds show little promise as a human food in normal times.     

Compositional and nutritional attributes of seeds from the multiple purpose tree Moringa oleifera Lamarck

Moringa oleifera Lam is a multipurpose tree cultivated to use as a vegetable, for spice, for cooking and cosmetic oil and as a medicinal plant. Owing to the use of its seeds as food and as a clarifying agent of turbid water some nutritional and antinutritional characteristics were studied. The mature seeds contained 332.5 g crude protein, 412.0 g crude fat, 211.2 g carbohydrate and 44.3 g ash per kg dry matter. The essential amino acid profile compared with the FAO/WHO/UNU scoring pattern requirements for different age groups showed deficiency of lysine, threonine and valine. The content of methionine + cysteine (43.6 g kg⁻¹ protein), however, was exceptionally higher and close to that of human milk, chicken egg and cow's milk. The seed extract agglutinated rabbit erythrocytes but did not show trypsin inhibitor and urease activities. Feeding rats with a diet containing the seed meal showed loss of appetite, impaired growth, lower NPU and enlargement of stomach, small intestine, caecum + colon, liver, pancreas, kidneys, heart and lungs and atrophy of thymus and spleen in comparison with rats fed on an egg‐white diet. The results indicated that consumption of M oleifera raw mature seeds should be viewed with some caution until suitable processing methods are developed to abolish the yet unknown adverse factors. © 1999 Society of Chemical Industry     

Couscous, a traditional Turkish food product: production method and some applications for enrichment of nutritional value

Traditional Turkish couscous, a cereal‐based product, is made by covering bulgur with milk and flour. Traditionally Turkish couscous was produced from different flours (soyflour and oat flour) and eggs. The nutrient composition of traditional couscous was 90.6% dry matter, 11.27% protein, 2.58% fat, 71.80% carbohydrate, 42.25 mg sodium, 365.62 mg potassium, 2.73 mg iron and 48.30 mg calcium. The calorie content of traditional couscous is about 1487.41 kJ 100 g^?1. The addition of soy and oat flours increased protein content and Ca, K and Fe levels. Sensory properties were also affected. Panellists preferred traditional couscous and couscous with eggs or soyflour over couscous with oat flour.     

The carbohydrate composition of cotyledons and hulls of cultivars of Lupinus angustifolius from Western Australia

The hulls and cotyledons from three Western Australian cultivars (Gungurru, Yorrel and Danja) of Lupinus angustifolius, all of low alkaloid content, were analysed separately for their carbohydrate content and composition. Only minor differences in composition between these three cultivars were observed. More notably, the cotyledons of all the cultivars contained levels of non-starch polysaccharides (NSP), ranging from 290 to 310 g kg^?1 dry weight considerably higher than had been measured previously in cultivars of this species. Galactose, arabinose and uronic acid residues accounted for approximately 67%, 13% and 10%, respectively, of the cotyledon NSP. Although only a small proportion of the cotyledon NSP is soluble, a much larger proportion could be extracted with hot EDTA treatment. The oligosaccharide content of the cotyledons ranged from 74 to 80 g kg^?1 dry weight. Cotyledons had very low contents of cellulose, lignin and starch. Hulls consisted predominantly of NSP, with values ranging from 856 to 891 g kg^?1 dry weight. Glucose, xylose, uronic acids and arabinose were the principal sugar residues present reflecting the compositions of the major constituent polysaccharides, cellulose, hemicelluloses and pectins. Only low levels of lignin were measured in hulls. Cotyledon NSP and hulls from these cultivars may have considerable value as sources of dietary fibre in the human diet.