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1.
Five different recently released Brazilian soybean cultivars (Bays, BR-10, Rio Balsas, Serido and Tropical) were compared for their proximate analyses and presence of antinutritional or toxic factors. As expected, the seeds are rich in proteins, varying from 360·7 to 485·4 g kg−1 flour, and they also have a high amount of fat (from 183·0 to 215·3 g kg−1 flour). Crude extracts from seeds of Bays, BR-10, Serido and Tropical were highly toxic to mice within 1–12 h, depending on the administration route (intraperitoneal, intramuscular or subcutaneous) and dose used while Rio Balsas was not. These acute effects were very similar to those produced by the soytoxin, a neurotoxin that has been recently purified from the commercial soybean sold in Brazil. The amount of trypsin inhibited in the presence of crude extracts ranged from 28·5 to 62·5 g kg−1 flour. Urease was also present and the seed lectin agglutinated preferentially rabbit erythrocytes. A heat treatment at 92°C for 1 min destroyed completely the toxic activity while the haemagglutinating and trypsin inhibitor activities were abolished within 5 min. At these conditions urease was still active. Due to its high protein content, lack of soytoxin, and low levels of trypsin inhibitor, lectin, and urease it is suggested that Rio Balsas could be an alternative for breeding programmes aimed to improve the nutritional quality of soybeans. ©1997 SCI  相似文献   

2.
Grain protein content affects the flour yield and breadmaking characteristics of wheat (Triticum aestivum L). In this study, grain protein yield, grain protein content, flour yield and loaf volume were quantified for four wheat cultivars (Inia, Carina, Kariega and SST 86) grown under six different soil fertility regimes in a long-term fertilisation and irrigation experiment at the University of Pretoria. The experimental design was a randomised complete block replicated four times, with fertility as the main plots and cultivars as the subplot treatments. Grain protein yield, flour yield, loaf volume and mixograph dough peak mixing time varied among cultivars and soil fertility situations. Grain protein content differed among cultivars, but mixograph water absorption and dough characteristics did not differ. The highest grain protein yield was 873 kg ha−1 for Carina and the lowest 527 kg ha−1 for SST 86. Grain protein content averaged 131 g kg−1 for Carina and 122 g kg−1 for Kariega. Breadmaking performance showed that in a well-balanced soil fertility situation, Kariega produced 1025 cm3 of loaf volume while Inia averaged 950 cm3. Grain protein yield increased with increasing soil fertility, but grain protein content, flour yield, loaf volume, water absorption and mixograph peak mixing time varied with soil fertility. The interaction between cultivar and soil fertility was significant for grain protein yield, grain protein content, flour yield, loaf volume and water absorption but not dough peak mixing time. The results indicate cultivar differences in breadmaking quality characteristics and that soil fertility status affects grain protein yield, grain protein content, flour yield, loaf volume potential and water absorption but not mixograph peak mixing time and dough characteristics. © 1999 Society of Chemical Industry  相似文献   

3.
The concentrations of isoflavones, especially daidzein and genistein, were determined by high performance liquid chromatography in 4 soybean cultivars and 26 soybean products. The total isoflavone content of the soybean cultivars was in the range of 525–986 mg per kg, and for soy products it was 32.9–795 mg per kg. Amongst the soybean products, the isoflavone content decreased in the order: soy sprouts, soy seeds, soy flour, soy milk, soy meals and soy sauce. Significant differences in the concentration of genistein and daidzein were observed between the commercial soy products and also within the soybean cultivars. The antioxidant activity of soybean and soy products correlated well with total phenolic content (TPC) and total isoflavones (TI), whereas TPC showed higher correlation with TI.  相似文献   

4.
A method for phytic acid determination in the feeds and faeces of pigs and poultry has been developed on the basis of capillary isotachophoresis. Phytic acid was extracted by 0.95 M HCl and separated from interfering compounds by iron precipitation. Complete formation of ferric phytate required 7 mol FeCl3 mol−1 phytic acid. Residual Fe3+ was estimated colorimetrically by the tiron reagent, and ferric phytate was dissolved in 1.5 M NaOH at 9 mol NaOH mol−1 Fe precipitated. Analyses were carried out using an electrolyte system with Cl as the leading anion, bis‐tris‐propane, and 2‐morpholinoethanesulphonic acid as the terminating anion. The recovery of phytic acid (added to hen faeces) using this procedure was 962 ± 24 g kg−1. The limit of determination of phytic acid was 0.3 µmol ml−1 extract. The amount of phytic acid in feeds ranged from 8.3 to 10.8 g kg−1 on a dry matter basis. Phytic acid P represented 112 g kg−1 total P in faeces of young pigs (40–60 kg) fed a feed with supplemental phytase (490 U kg−1), 153 g kg−1 total P in faeces of finishing pigs and 185 g kg−1 total P in faeces of non‐lactating sows. Excreta of laying hens contained 23.7 g phytic acid kg−1 dry matter (362 g kg−1 total P). The isotachophoretic method is sufficiently simple and reproducible to be used for routine analyses of feeds and faeces. © 2000 Society of Chemical Industry  相似文献   

5.
Phytic acid content of various cultivars showed a narrow variation: 7.48-8.00 g kg?1 and 6.47-6.68 g kg?1 for chickpea (Cicer arietinum L) and black gram (Vigna mungo L), respectively. Phytic acid was lowered significantly by the common methods of domestic processing and cooking including soaking, cooking, autoclaving and sprouting of the legume grains. Sprouting had the most marked phytic acid lowering effect followed by autoclaving and soaking. Cooking of soaked seeds lowered phytic acid by 20-26% in chickpea and 35-40% in black gram grains whereas the loss was 7-11% and 6-9% in these pulses, respectively, when unsoaked seeds were cooked.  相似文献   

6.
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  相似文献   

7.
We studied the effects of different processing treatments, including soaking, steeping, boiling in water and germination and chemical treatments with H2SO4, HCl, lime and NaHCO3, on the removal of a neurotoxin, β‐N‐oxalyl‐L ‐α,β‐diaminopropionic acid (β‐ODAP), from Indian vetch (Iv) and addition of detoxified Iv in chapatti. The toxin level was quantified by using thin‐layer chromatographic and spectrophotometric methods. Maximum removal was observed after steeping in water at 60–70°C for 8 h with seven rinses. The samples were dried, milled into flour and added to chapatti at different levels. Sensory attributes revealed that the chapattis were most acceptable by judges when supplemented with up to 200 g kg−1 of flour. The protein level of Iv flour increased from 124 to 174 g kg−1 as result of supplementation at 300 g kg−1. Biological studies with albino rats showed that detoxified Iv had a better impact on nutritional status. Copyright © 2006 Society of Chemical Industry  相似文献   

8.
Phytic acid or phytate is a chelating agent, which is involved in binding minerals (such as K+, Ca2+, Zn2+, Fe2+, etc.) and making them unavailable for dietary absorption. It is also involved in forming complexes with protein, making protein less soluble, and affecting enzymatic degradation, gastric absorption, and malting processes. The phytic acid and protein contents of barley grains are influenced by genetic and environmental factors. This study investigated differences in phytic acid and protein contents in grains of 100 barley (Hordeum vulgare L.) genotypes or cultivars. Eight barley cultivars were selected and grown at seven locations for two years to study the effects of genotypic and environmental factors on phytic acid content (PAC) and its relation to malt quality. The phytic acid contents of 100 barley genotypes ranged from 3.85 mg g−1 to 9.85 mg g−1, with a mean of 7.01 mg g−1. The effects of cultivars, locations, time and their interactions were highly significant, but the variation was mainly attributed to the environment (location and time). The correlation between grains phytic acid and protein content was significant and positive. Whereas, the correlation between grain phytic acid content and malt extract was significant and negative. The relationship between phytic acid and protein contents of barley is important as it affects the malting process, malt yield and quality, and final beer quality. Barley grain for malting and feed uses should have low phytic acid content.  相似文献   

9.
《Food chemistry》2005,89(1):49-52
Phytic acid and protein contents in grains of japonica rice cultivars collected from different areas of China were assayed in this study. Meanwhile, a multi-location trial was conducted to determine phytic acid content of 24 cultivars grown at 4 locations with wide differences in ecological conditions. For 72 cultivars, phytic acid content ranged from 0.685% for Xiu217 to 1.03% for Huai9746, with a mean of 0.873%, and protein content ranged from 6.45% for Xiu52 to 11.1% for K45, with a mean of 8.26%. There was no significant correlation between grain phytic acid and protein content, suggesting the possibility of breeding japonica rice cultivars with low phytic acid and high protein contents. The effects of cultivars, environments (locations) and their interactions on phytic acid content were all highly significant, with the location having the largest effect. The highly significant interaction between cultivar and environment suggests that the correct evaluation of rice germplasm by phytic acid content should be conducted in multi-environments.  相似文献   

10.
Soysaponins are considered major bioactive components. Ethanol extractives prepared from mature soybean and germinated seeds (0–4 days) were examined for saponin content (found to be 2.8 and 6.1–8.9%, respectively). The saponin content increased 3.2 times after germination. The predominant hydrolytic product of saponin – soysapogenol I – content increased from 1.8 to 7.3% during the course of germination. Defatted soy flour, soy protein isolate and toasted flour contain saponins at 2.3–3.5%, suggesting that the germinated soybean seeds are the richest source of saponins among soybean products.  相似文献   

11.
Buttermilk fermentation at 25, 30 and 35°C for 12, 18 and 24 h brought about a significant increase in non-phytate and HCl-extractable phosphorus with a corresponding decline in phytate phosphorus of a rice-defatted soy flour blend mixed in a 50 : 50 proportion. The HCl-extractabilities of calcium, iron, zinc, copper and manganese from the rice-defatted soy flour blend also improved. Higher HCl-extractability of minerals may be partly ascribed to the decreased content of phytic acid, as a significant negative correlation between the phytic acid and HCl-extractability of dietary essential minerals was obtained.  相似文献   

12.
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  相似文献   

13.
The simple semiquantitative picrate method for the determination of total cyanogens in cassava flour has been modified by increasing the concentration of the picrate solution used to make up the picrate papers, such that a linear Beer's Law relation between absorbance and cyanogen content is obtained over the range 0–800 mg HCN equivalents kg−1 cassava. The method has been adapted to determine the total cyanogen content of cassava roots and the results compared using the picrate method and the acid hydrolysis method for six different roots from five cultivars. The agreement between the results is satisfactory. The simple method for determination of total cyanogens in cassava roots in the field is available in kit form. The methodology has been modified to allow determination of the three different forms of cyanogens present in cassava flour, viz HCN/CN, acetone cyanohydrin and linamarin. HCN/CN is determined by the picrate method in which cassava flour is reacted with 0.1 M sulphuric acid for 3 h at room temperature. HCN/CN plus acetone cyanohydrin is also determined by the picrate method after treating cassava flour with 4.2 M guanidine hydrochloride at pH 8 for 3 h at room temperature. A comparison has been made of the amounts of the three cyanogens present in six cassava flour samples using the semiquantitative picrate and the acid hydrolysis methods. The agreement between the two methods is satisfactory, which shows that the new methodology works well. The picrate method for determination of the three cyanogens in cassava flour is also available as a kit. © 1999 Society of Chemical Industry  相似文献   

14.
Changes in the proximate composition of developing seeds of sandalwood (Santalum spicatum R Br) were quantified. The developing fruits were collected regularly over a period of 5 months commencing 14 days after flower opening. Rapid deposition of seed lipid began at about 91 days after flowering (DAF) at a level of 4 g kg−1 and continued to about 396 g kg−1 at 147 DAF. Protein and ash contents displayed similar trends to that of lipid with a corresponding decrease in moisture content. Fatty acid analysis of the seed oil demonstrated marked changes in composition during seed development. In particular, major increases in oleic and ximenynic acids were noted with corresponding decreases in the other fatty acids. © 1997 SCI.  相似文献   

15.
BACKGROUND: The stage of fruit ripeness at the time of harvest determines the final quality of ripe fruit. In this study, changes in the chemical composition of seed kernels from the oleaginous gourd Lagenaria siceraria (Molina) Standl. during maturation were evaluated to determine the best time to harvest the berries. Two cultivars (round and oval berry) were studied at three maturation stages (30 and 50 days after fruit set (DAFS) and complete plant whiteness (CPW)). RESULTS: Seed kernels were rich in oil (527.2–544.6 g kg−1), protein (402.8–403.3 g kg−1), minerals and energy. Maturation influenced the chemical compounds of the two cultivars differently. Best quantities of these components were reached at 50 DAFS. However, protein bioavailability was better at 30 DAFS and CPW in the round and oval berry cultivars respectively. Lagenaria siceraria oils were of good quality, containing an abundance of essential fatty acids (647.2–667.0 g kg−1). CONCLUSION: Both cultivars of L. siceraria should be harvested at 50 DAFS owing to the good nutritional properties of their seeds and oils. However, to obtain best‐quality proteins, round and oval berry cultivars should be harvested at 30 DAFS and CPW respectively. The results of this study will be useful in reducing the production time of fruits and improving the nutritional quality of their seeds. Copyright © 2011 Society of Chemical Industry  相似文献   

16.
The protein and trypsin inhibitor activity in pods and seeds of winged bean (Psophocarpus tetragonolobus (L) DC) increase, and in the pod hull decrease, with the maturity of plant. The seeds of 21 cultivars both exotic and of Indian origin cultivated on marginal alkaline soil (pH 8.7) were analysed for protein (36.4–45.3) and amino acid composition (lysine 4.8 to 6.7).  相似文献   

17.
Isoflavone levels and isoflavone chemical composition in soybeans vary between planting locations although the exact factors which control isoflavone biosynthesis are unclear. We compared levels of 12 isoflavones in soybean seeds of six cultivars grown in four different locations in Ohio in 2002 as determined by high‐performance liquid chromatography. Antioxidant activity contained in plant‐based foods can improve food oxidative stability and phenolics and isoflavones have proven active in food systems. Radical scavenging activity was assessed using the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical. Total phenolics (TPCs) were determined by using Folin–Ciocalteu reagent. Total isoflavones (TIs) varied five‐fold (1573–7710 nmol g?1) between seeds from the various location–cultivar combinations. One location (Wooster, Ohio) produced seeds containing half the isoflavones as the other locations tested apparently due to poor growing conditions. The cultivars could be divided into two groups based on TI, one having approximately 50% more isoflavones. Surprisingly, across the entire data set, with increasing TI, the proportion of isoflavones accounted for by the daidzein family increased due primarily to malonyl daidzin. DPPH scavenging did not differ significantly by location or cultivar (P > 0.05) and did not correlate with TPC or TI. Profiling soybean isoflavones could help elucidate how isoflavone biosynthesis is regulated and lead to better disease resistance of soybean crops and soy foods with greater health benefits. Copyright © 2007 Society of Chemical Industry  相似文献   

18.
Tarhana, supplemented with 150 g kg−1 full‐fat soy flour, was extruded at different extrusion conditions (barrel temperature: 80–120°C; screw speed: 100–300 rpm; feed rate: 10–20 kg h−1 ) using a twin‐screw extruder. The effect of extrusion conditions on the in vitro digestibility (PD) of the protein and protein solubility (PS) was investigated using response surface methodology. Regression equations for predicting PD and PS were developed. While the barrel temperature had a significant effect on PD (P <0.1), feed rate was the most significant variable on PS of the samples (P<0.05). Since the protein solubility should be high for the instant properties of extruded soy tarhana soup, it is suggested that soy tarhana should be extruded at low feed rates (ie high residence times) while high barrel temperatures should be achieved for the inactivation of antinutritional factors present in the soy flour. © 1999 Society of Chemical Industry  相似文献   

19.
The seeds of 28 species from ‘cerrado’, a typical savanna ecosystem of Brazil, were analysed for total lipid contents and fatty acid distribution. The seeds of 10 species presented contents above 150 g kg−1, the highest yield reaching 335 g kg−1. Distribution of fatty acids based on polyunsaturated compounds seems to be rare in seed oils from ‘cerrado’: only three seed oils were found to be based on linoleic acid and none on linolenic acid. Eight seed oils, four of them Fabales, presented palmitic acid as a dominant constituent. Half of the species presented oleic acid based seed oils. Two species stand out for unusual fatty acid distribution: Qualea grandiflora (Vochysiaceae) with 171 g kg−1 of seed oil presenting 723 g kg−1 of lauric acid and Serjania erecta (Sapindaceae) with 256 g kg−1 of seed oil presenting 623 g kg−1 of eicosenoic acid.  相似文献   

20.
Maize flour (Zea mays) (M), Lima bean flour (Phaseolus lunatus) (B) and blends of these in proportions of 75M/25B, 50M/50B and 25M/75B (w/w) were extruded and their nutritional quality evaluated. Extrusion was done with a single screw extruder at 160 °C, 100 rpm and 15.5% moisture. In vitro protein digestibility (87%) was higher in the extruded products. Available lysine and resistant starch were highest in 50M/50B raw flour (59.5 g kg−1 protein, 67.9 g kg−1, respectively) but decreased after extrusion (45.5 g kg−1 protein, 16.6 g kg−1, respectively). The same treatment had the lowest available starch (561.6 g kg−1 flour, 507.9 g kg−1 extrudate). Total dietary fiber in the 50M/50B raw flour blend was 144 g kg−1 versus 176 g kg−1 in its extrudate. This was most noticeable for soluble dietary fiber, which increased from 10.6 g kg−1 to 79.4 g kg−1 after processing. Extrusion of blends is feasible up to a 50% bean inclusion level, which improves the nutritional value of the expanded product.Copyright © 2006 Society of Chemical Industry  相似文献   

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