Effects of infestation on the nutrient content and physiocochemical properties of two cowpea ( Vigna unguiculata) varieties

Two cowpea varieties (Ife-brown and Kano-white varieties) were used for the study. The effects of insect infestation on the chemical composition and physicochemical properties of these cowpea seeds were studied. The proximate composition, mineral content, total starch, total soluble sugars, bulk density, fat and water absorption capacities, viscosity, gelation capacity and emulsion properties of infested cowpea varieties were compared with those of uninfested cowpeas. Effects of infestation on nitrogen solubulity and on the protein fractions were also determined. lnfestation depleted the protein, starch and soluble sugar contents of cowpeas. Oil and water absorption capacities were increased while emulsification, foam and viscosity properties were reduced. The nitrogen solubility pattern was altered. Uninfested Kano-white cowpeas (UKW) possessed better foam properties than uninfested Ife-brown cowpeas (UFB). On the other hand, UFB had better emulsification properties than UKW.     

Evaluation of selected food attributes of four advanced lines of ungerminated and germinated Nigerian cowpea (Vigna unguiculata (L.) Walp.)

The chemical composition and functional properties of ungerminated and germinated seeds of four advanced lines of cowpeas (IT81D-699, IT82E-18, IT84S-2246-4 and TVx 3236) were investigated. Ungerminated seeds contained 20.1 to 25.8% crude protein, 2.0 to 2.2% lipid, 115.1 to 210.0 mg phyticacid/100 g and 8.9 to 9.6 mg iron/100 g. The polyphenol contents of the brown- and cream-colored beans were similar (192.0 to 196.0 mg/100 g) but were significantly (p<0.05) higher than the amount (99.8 mg/100 g) found in the white beans. Germination increased the crude protein content, total phosphorus content, nitrogen solubility, fat absorption capacity and foam capacity but decreased ether extract, polyphenol and phytic acid contents, water absorption capacity, bulk density and foam stability of all cowpea lines. Incorporation of up to 0.2 M NaCI improved foam volume. Ungerminated seeds had high water (2.3–3.2 g/g) absorption capacities, while germinated seeds had high fat (3.1–3.6 g/g) absorption capacities. TVx 3236 and IT81D-699 might be selected for combining such characteristics as high crude protein, low phytic acid content and good foaming properties into a single cowpea line through breeding.     

醋制对黑豆蛋白含量及多肽ACE抑制活性的影响

为考察醋制对黑豆蛋白含量及多肽ACE抑制活性的影响,为对黑豆醋浸过程中蛋白组分及含量变化进行分析,并对相应ACE抑制肽活性进行测定。黑豆经醋浸不同时间后,采用顺序抽提法提取清蛋白、球蛋白、醇溶蛋白和谷蛋白,并采用凯氏定氮法及SDS-PAGE电泳进行定量和定性分析;各蛋白组分经胃蛋白酶水解,经超滤(截留分子量3 k D)后收集滤液,获得多肽组分,RP-HPLC法进行ACE抑制活性评价。结果表明:经醋浸14 d后,黑豆总蛋白含量变化幅度小于±0.5%;清蛋白含量由55.13%(0 d)降低至9.61%(14 d);球蛋白由7.04%(0 d)增加到20.34%(14 d);醇溶蛋白由0.81%(0 d)增加到1.72(14 d);谷蛋白由21.11%(0 d)增加到59.45%(14 d),含量最高。醋浸处理降低了清蛋白源多肽的ACE抑制活性,但提高了球蛋白、醇溶蛋白及谷蛋白多肽的ACE抑制活性,其中,谷蛋白多肽抑制率由18.18%(0 d)增加至37.58%(14 d),抑制活性升高。醋浸可改变黑豆各蛋白组分的含量和对应多肽的ACE抑制活性,其中,谷蛋白含量及其多肽ACE抑制活性均有增加。研究结果表明可进一步采用分离纯化技术从谷蛋白多肽中获得高活性降压肽。     

Cultivar and processing effects on the pasting characteristics,tannin content and protein quality and digestibility of cowpea (Vigna unguiculata)

Four popular West African local cultivars of cowpea (Vigna unguiculata), with distinctly different seed coat colors, were evaluated for their relative amylograph pasting characteristics, condensed tannin content, in vitro protein digestibility and Tetrahymena protein efficiency ratio (t-PER). The effects of roasting and dehulling on these properties were also determined. There were wide variations in the hot paste viscosity characteristics of the different cultivars studied. The raw cowpea flour samples exhibited maximum paste viscosities ranging between 260 Brabender Units (BU) for the Mottled cultivar and 460 BU for the cream-colored Blackeye cultivar. Cowpea cultivars with the greatest peak viscosities showed low stabilities to extended cooking. Roasting depressed paste viscosity properties of all the cowpea cultivars studied. Tannin concentrations were 0.3–6.9 and 7.2–116 mg CE/g flour from whole cowpea seeds and seed coats respectively, increasing with intensity of seed color. Although dehulling removed 98% of the tannin content of raw cowpeas, improvement in protein quality as a result of dehulling was observed for only the highly-pigmented Maroon-red variety. Roasting significantly improved digestibility and more than doubled the t-PER of all cowpea cultivars studied. Roasted cowpeas possess adequate nutritional and functional qualities as protein supplements in cereal-based weaning foods. However, it appears that dehulling is necessary to enhance the nutritional quality of the highly pigmented cultivars of cowpea.     

Production and organoleptic assessment of akara from bambara groundnut (Voandzeia subterranea (L.) Thouars)

Bambara groundnut (BGN) seeds were pretreated by soaking, dry-milling or autoclaving and used to produce pastes which were then used to prepare akara. Proximate analysis and organoleptic tests were conducted. Method of pretreatment affected the proximate composition of the akara. The moisture, protein and fiber contents of akara prepared from BGN seeds, which were cracked and soaked or autoclaved, were significantly (p 0.05) different than those from soaked whole grains and flour. The cooked batch weights of the akara ranged from 258–272 g, akara from soaked whole and autoclaved seeds having the lowest and highest values, respectively. Akara from autoclaved BGN seeds was more highly preferred by panelists compared to akara from other pretreatments. Except for appearance and color, no significant differences were found between BGN akara and the cowpea akara used as reference. Heat treatment of BGN seeds prior to dehulling appeared to influence the level of acceptability of the akara.     

The effects of sun-drying surfaces and packaging materials on the storability of cowpea ( Vigna unguiculata) seed

The effects of sun-drying cowpea seeds for three hours on cement (CS), wood (WS), and corrugated iron sheet (CIS) surfaces and packaging separately in polyethene and jute bags were studied. Moisture-gain, and resistance to insect and mold damage were monitored monthly for six months, while proximate analyses on day zero and at the 6th month were conducted. Results showed that the three-hour sun-drying of cowpea seeds on reflective surfaces (CIS and CS) enhanced the rate of moisture-reabsorption during storage and consequently, the degree of mold and insect damage irrespective of the packaging material employed. Crude fat, fiber and ash contents, unlike protein and moisture contents, remained virtually constant (p 0.05). In this study, the wood surface and polyethene bag were the most preferred treatments to store sun-dried cowpea seeds for about 5.7 months.     

Antinutritional factors in pulses as influenced by different levels ofCallosobruchus chinensis L. (Bruchids) infestation

Influence of six (10, 20, 30, 40, 50 and 60%) levels of bruchids infestation on the contents of selected antinutritional factors-phytic acid, saponins, trypsin inhibitors activity (TIA) of three (chickpea, red gram, and green gram) pulses was studied. Comparisons of infested samples were made with uninfested controls of each pulse. The three antinutritional factors viz TIA, phytic acid and saponins were found to increase with the increase in the level of infestation. All the control pulse values of the phytic acid, saponins and TIA were significantly lower than those of the infested samples. Barring a few exceptions, the differences in the contents of antinutritional factors in pulses infested at different levels were significant (P<0.05).     

Field and model analysis of the effect of water deficits on carbon and nitrogen accumulation by soybean,cowpea and black gram

Identification of the key physiological traits that limit carbon and nitrogen accumulation in grain legumes is an important step in understanding how to improve their productivity in water-limited environments. A growth model was used to assist in the interpretation of two field experiments comparing the performance of soybean, cowpea and black gram under water deficits, and to assess the importance of different physiological traits in determining productivity in these grain legumes. The coefficients of the relationships in the model describing leaf growth, carbon and nitrogen input, seed growth, and the water budget were obtained from the literature and from glasshouse and field experimentation.The principal differences in input variables to model the growth of soybean, cowpea and black gram were those describing leaf emergence rate, N fixation during seed filling, and the biochemical composition of the seeds. The relationship describing the response of leaf-area growth, radiation-use efficiency and N fixation to soil water content differed little among species. Similarly, those input variables associated with radiation interception and solar radiation-use efficiency were held constant for the three species.An important difference among the species was that N fixation continued during seed growth in soybean but did not in cowpea or black gram. As N is translocated from vegetative tissue to developing seeds, the absence of N fixation during seed-filling results in a more rapid decline in canopy photosynthetic capacity, thus limiting the potential productivity of cowpea and black gram. The study also highlighted the importance of the delay in reproductive development in cowpea and black gram in response to water deficits. The tendency for cowpea to yield higher under water-limited conditions was more closely related to the ontogenetic flexibility of the species than to any other physiological traits or response.     

Bioavailability of iron from four different local food plants in Jordan

The bioavailability of iron from local plants(black cumin seeds, milk thistle seeds, sesame seedsand thyme leaves) was investigated. Apparentabsorption of iron was calculated by subtracting fecal iron(using total collection of feces) from iron intake inSprague-Dawley rats. Two trials of animal feeding wereperformed. Liver and serum concentrations of iron, andserum hemoglobin concentration were taken as responseparameters for the bioavailability. Dry thyme wasparticularly rich in iron (117.2 mg/100 g dry matter)and milk thistle seeds in crude fiber (25 g/100 g drymatter). Rats fed the dry thyme diet or thatsupplemented with 5% egg white died but when the dietwas supplemented with 10% egg white, the animalssurvived. Iron intake and apparent and total ironabsorption were highest for the rats fed the drythyme-egg white diet. Liver weights for the groups fedblack cumin seeds and dry thyme were significantlyhigher (p < 0.05) than those for the groups fed milkthistle and sesame seeds. Liver content of ironwas highest for the animals fed black cumin seeds.Serum iron content increased significantly (p < 0.05)for the animals fed black cumin seeds, and serumhemoglobin concentration increased significantly (p < 0.05) in the groups fed milk thistle seed and blackcumin seed diets, but decreased for the group fed thethyme-egg white diet. It is concluded from this studythat iron was better utilized from black cumin seedsas indicated by liver storage of iron. On the otherhand, thyme had the highest iron absorption but lowestutilization.     

不同颜色防虫网覆盖栽培对豇豆生长发育的影响

研究了不同颜色(白色、黑色、红色、蓝色、绿色、银灰色)防虫网覆盖对栽培豇豆生长发育的影响。从豇豆的生育期、株高、茎粗、叶面积及叶绿素含量指数、产量和病虫害等方面综合考虑，在三亚地区绿色防虫网是较适合豇豆栽培的覆盖材料。     

Effects of prolamin on the textural and pasting properties of rice flour and starch

Prolamin is a major class of rice proteins but its influence on the physicochemical properties of rice is not clear. Rapid Visco Analyser (RVA) and TA-XT2 TPA textural analyses were performed on rice starch with the addition of prolamin extracted from three rice cultivars (Hitomebore, M103 and Amaroo), and on rice flour with the prolamin removed by propan-2-ol extraction. Addition of prolamin to rice starch was found to cause a significant (P<0.05) increase in RVA breakdown viscosity but significant (P<0.05) decreases in hardness, adhesiveness and gumminess of the starch gel. Similarly, when prolamin was removed from rice flour, exactly the opposite effect was observed. Addition of prolamin to rice starch also caused it to absorb water faster during cooking but the gelatinised starch absorbed less water compared with control samples without prolamin.     

Effects of soybean genotype and growing location on oil and fatty acids in tofu

Soyfood products like tofu are becoming popular among American consumers due to health benefits. In order to increase production to meet consumer demands, it is imperative that factors that effect quantity and quality of tofu be characterized. The present study was conducted to determine the effects of soybean genotypes and growing locations on contents of oil and fatty acids in tofu which was prepared from twelve soybean genotypes (BARC-8, BARC-9, Enrei, Hutcheson, MD86-5788, Nakasennari, S90-1056, Suzuyutaka, V71-370, V81-1603, Ware, and York) grown at three southern U.S. locations (Huntsville, Alabama; Princess Anne, Maryland; and Petersburg, Virginia) during 1995. The results showed that tofu quality was determined by the soybean genotype. The tofu made from seeds of high seed-protein and low seed-oil genotypes (BARC-8 and BARC-9) resulted in tofu with low contents of oil (15.8 and 11.3 g/100g, respectively) and total saturated fatty acids (2.59 and 160 g/100g, respectively). Tofu made from seeds of conventional grain type genotypes, such as Hutcheson, resulted in higher oil (24.0 g/100g) and total saturated fatty acids (3.80 g/100g) contents in tofu. Effects of growing environment on contents of oil were not significant but tofu made from seeds grown in Alabama had significantly higher content of total saturated fatty acids (3.50 g/100g) as compared to that made from seeds grown in Maryland (2.88 g/100g) or Virginia (2.96 g/100g). Tofu made from seeds of large and medium-seeded genotypes had higher contents of total monounsaturated fatty acids in tofu as compared to that made from small-seeded genotypes. Highly positive correlation existed between contents of oil, 18:1, 18:2, total saturated, and total unsaturated fatty acids in the seeds and their contents in the tofu (+0.80, +0.75, +0.79, +0.62, +0.68, respectively). These results indicated that tofu quality is governed by soybean genotype, seed size and growing location.     

The effects of sun-drying surfaces and packaging materials on the storability of cowpea (Vigna unguiculata) seed.

The effects of sun-drying cowpea seeds for three hours on cement (CS), wood (WS), and corrugated iron sheet (CIS) surfaces and packaging separately in polyethene and jute bags were studied. Moisture-gain, and resistance to insect and mold damage were monitored monthly for six months, while proximate analyses on day zero and at the 6th month were conducted. Results showed that the three-hour sun-drying of cowpea seeds on reflective surfaces (CIS and CS) enhanced the rate of moisture-reabsorption during storage and consequently, the degree of mold and insect damage irrespective of the packaging material employed. Crude fat, fiber and ash contents, unlike protein and moisture contents, remained virtually constant (p < or = 0.05). In this study, the wood surface and polyethene bag were the most preferred treatments to store sun-dried cowpea seeds for about 5.7 months.     

Effect of Japanese mint (Mentha arvensis) oil as fumigant on nutritional quality of stored sorghum

Japanese mint (Mentha arvensis) oil (JMO) can be used effectively as fumigant againstSitophilus oryzae in stored sorghum. The effect of JMO at a dose of 166 µl/l of space on nutrient composition and protein quality was studied in infested and uninfested sorghum grains stored for 3 months. The results revealed non significant effect of JMO on gran moisture, total ash, crude fibre, crude fat, crude protein and fat acidity in infested and uninfested grains at the end of 3 months storage. The JMO treatment had small but significant effect on reducing and nonreducing sugars. The values of Protein Efficiency Ratio (PER) for uninfested JMO treated grains, infested JMO treated grains and for untreated control stored for 3 months were 1.11, 1.07 and 1.09, respectively against control casein diet for which it was 2.15.     

南方和黄淮海地区大豆地方品种贮存蛋白组分含量遗传变异的初步分析

我国南方和黄淮海地区的７２个大豆地方品种的贮存蛋白组分含量分析结果表明，大豆种子贮存蛋白各组分平均含量为球蛋白．２４．３９、清蛋白５．７７、醇溶蛋白１．７４、谷蛋白５．２７（ｇ／１００ｇ），其遗传变异丰富。南方与黄淮海地区品种间的４种贮存蛋白组分含量平均数及方差均无显著差异。     

Use of peanut and cowpea in wheat-based products containing composite flours

Cowpeas and peanuts are legumes of major dietary and economic importance. They are favored worldwide because of their palatability, contribution to nutritional status, and low cost as a protein source compared to animal protein. Flours processed from cowpeas and peanuts have unique physico-chemical and sensory properties when used in composite flour mixtures. Appropriate blends of cowpea and peanut flours to replace wheat flour in Chinese-type noodles, muffins, and tortillas were determined using modelling and optimization procedures. For noodles, 15% peanut flour and 8% cowpea flour supplementation produced an acceptable product with high protein content (21%). For wheat flour replacement in muffins, up to 43% cowpea and up to 44% peanut flours may be used. However, when wheat flour replacement is 50% or greater, cassava flour should comprise 56 to 72% of the blend with a few exceptions. In tortillas, 24% cowpea and 46% peanut flours produced products similar in quality characteristics to those made from 100% wheat flour. The systematic approach used in these studies is more efficient than the traditional substitution method to optimize sensory qualities of wheat-based products containing composite flours.     

甘蓝型油菜中5个脂酰-ACP硫酯酶基因的克隆与功能初步分析

为了解影响油菜种子含油量的关键基因,从高含油量(HO)和低含油量(LO)甘蓝型油菜中克隆了5个脂酰-ACP硫酯酶(fatty acyl-ACP thioesterase,FAT)的基因.序列分析表明这5个FAT基因在HO和LO油菜基因组之间没有序列差异.5个FAT基因分别命名为:BnaA.FATA.a、BnaC.FAT...     

Comparison of different rice flour- and wheat flour-based butter cookies for acrylamide formation

Acrylamide (AcA) contents of different rice flour- and wheat flour-based butter cookies baked at 130 °C for 20, 55, or 90 min were investigated. AcA contents of different flour-based cookies increased with baking time. Color parameters in terms of CIE L*, b*, C*, and ΔE values showed significant opposite correlation to the AcA formation in each of the raw flour cookie. The cookies based on white rice flour had the lowest AcA contents ranging from not detectable (ND) to 204 μg/kg, followed by cookies based on brown rice flour (ND to 450 μg/kg), white wheat flour (155 μg/kg to 661 μg/kg), and whole wheat flour (306 μg/kg to 982 μg/kg). Considerably lower AcA levels were found in the rice flour-based cookies than in the wheat flour-based cookies, as well as in the milled flour-based cookies than in the whole-grain cookies. Although the flour source was considered to play a primary role in determining the AcA content, AcA content was apparently not dependent on the quantities of reducing sugars and free asparagine in the starting raw flour and cookies during baking. In summary, given its reducing potential for AcA formation, rice flour could be used in the production of cookies safe from heat-induced contaminants.     

Root deterioration in the potato early dying syndrome: Causes and effects of root biomass reductions associated with colonization byVerticillium dahliae

Russet Burbank potatoes were grown in the greenhouse in a split-root culture system to assess the impact of pathogens associated with the Potato Early Dying Syndrome (PED) on root deterioration. Plants were grown with all, half, or none of the root system in steamed soil infested withVerticillium dahliae, or in field soil infested withV. dahliae and other PED pathogens. The direct impact of pathogens on root deterioration versus indirect effects resulting from premature senescence of the whole plant was evaluated. Root biomass did not differ significantly between root halves from the same plant in infested and uninfested soil. Root biomass from plants with both halves of the root system in uninfested soil was usually greater than from plants with one or both halves growing in infested soil. Root biomass decreased rapidly after plant stems were inoculated with conidial suspensions ofV. dahliae. Root deterioration in PED was associated with premature senescence of foliar tissue and occurred independently of root colonization by root-colonizing pathogens.     

Biological utilization of vegetable peas: Effect of cooking and varietal differences

The flour of raw as well as cooked vegetable pea cultivars (Arkal and Bonneville) was used for biological evaluation of their protein quality. Cooking did not have a significant influence on the food intake. There were some differences in the food as well as protein intake and gain in body weights of rats when fed uncooked or cooked pea flour diets. Varietal differences did not seem to influence on apparent digestibility, true digestibility, biological value, net protein utilization and utilisable protein but cooking brought a significant (p<0.05) improvement in all of above mentioned parameters. Varietal differences as well as cooking exhibited no influence or serum protein concentration.