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1.
Some nutritional and antinutritional characteristics and biological value of Bauhinia purpurea L seeds were studied. The mature seeds contained (g kg-1 as is) 271·7 crude protein, 58·7 crude fibre, 124·5 crude fat, 29·3 ash and 515·3 carbohydrates. Potassium, phosphorus and iron occurred in higher concentrations when compared with commonly consumed legumes. The globulins and albumins together constituted major storage proteins (82% total protein). The essential amino acid profile of total seed proteins compared well with the FAO/WHO reference pattern except for a deficiency of sulphur-containing amino acids and tryptophan. When compared with the globulins, the albumins appeared to be a rich source of cystine, methionine, threonine, lysine and tryptophan. Seed lipids contained high levels of the unsaturated fatty acids, oleic and linoleic, which accounted for 62·6% of total fatty acids recovered. Both dry heating and autoclaving significantly reduced the antinutritional compounds. The in vitro protein digestibilities of raw, dry-heated and autoclaved seeds were 59·5, 72·3 and 78·7%, respectively. True digestibility and net protein utilisation were significantly higher in processed seed samples compared with raw seeds. Regarding utilisable protein, autoclaved samples exhibited relatively higher values than raw seeds. © 1997 SCI.  相似文献   

2.
In several tropical forage species the neutral detergent extraction used to determine cell wall and cell contents fractions solubilised a substantial UV‐absorbing polymeric fraction which appeared to be a soluble lignin–carbohydrate complex. A crude product was isolated from spear grass (Heteropogon contortus) with a yield of 30 g kg?1. In other forages an acetyl bromide method was used to estimate lignin extractable by neutral detergent. For eight species of tropical grasses this gave the following values: Aristida calcyna, 38; Mitchell grass (Astrebla squarrosa), 37; Chloris gayana, 31; Eragrostis sp, 37; spear grass, 49; Iseilema membranaceum, 35; Panicum maximum, 36; Sorghum sp, 42; Themeda triandra, 79 g kg?1. The levels in two legumes were: Alysicarpus bupleurifolius, 29; Macroptilium atropurpureum, 27 g kg?1 dry matter. Sequential extractions on spear grass and Mitchell grass showed that most of the 50% dioxan‐soluble fraction was also soluble in neutral detergent, raising the possibility that ‘dioxan lignin’, on which studies of forage lignin structure in other species have been conducted, would be found in the cell contents fraction rather than in the fibre fractions on which lignin analyses have been performed. Addition of dioxan extractives reduced the in vitro neutral detergent fibre (NDF) digestibility of spear grass and Mitchell grass. © 2002 Society of Chemical Industry  相似文献   

3.
The effects of seed treatments, including cooking, popping, germination and flour air classification on several components of Amaranthus caudatus and A. cruentus seeds, including oil, sugars, fibre, minerals and vitamins were studied. The lipid, crude and dietary fibre, ash, and sugar contents were 71, 43, 140, 30 and 18 g kg?1 in raw A. caudatus and 85, 39, 134, 40 and 22 g kg?1 in raw A. cruentus seeds, respectively. Sucrose was the dominant sugar in the raw and thermal treated seeds of both species, while glucose and galactose were the dominant ones in the high protein and the germinated seed flours. Phosphorus, potassium, magnesium and calcium were the dominant minerals in the raw seeds of both species. Air classification increased the content of minerals by more than 35% while thermal treatments did not affect their content and germination increased the calcium and zinc contents. The ascorbic acid contents were 0.030 and 0.023 g kg?1 sample in raw A. caudatus and A. cruentus seeds, respectively. All the treatments reduced the ascorbic acid content, with a high effect for the air classification and the germinated seeds dried at 90 °C. The levels of vitamin B complex, including niacin, niacinamide, pyridoxine and riboflavin were increased in the high protein flour fraction (protein contents of these fractions of A. caudatus and A. cruentus were 263.9 g kg?1 and 246.6 g kg?1, respectively) and decreased in the thermal treated flours. Germination mostly increased the amounts of those vitamins while drying reduced their amounts. Copyright © 2005 Society of Chemical Industry  相似文献   

4.
Some nutritional and anti-nutritional characteristics of mucuna (Mucuna utilis (Wight) Burck) bean seeds were studied. The mature seeds contained 264 g crude protein, 63 g crude fibre, 41 g crude fat, 37 g ash and 595 g carbohydrates kg?1 DM. The essential amino acid profile compared well with the FAO/WHO scoring pattern except for a deficiency of sulphur-containing amino acids. Mineral composition was similar to those reported for most tropical grain legumes. Raw mucuna seed samples contained moderately high levels of anti-tryptic activity (2170 trypsin units inhibited g?1 DM), but this was completely destroyed by cooking. The other anti-nutritional factors (phytate, cyanide and tannins) are probably of little nutritional significance provided that the beans are properly processed. The in-vitro protein digestibility of raw and cooked beans were 71·5 and 80·3 %, respectively. In view of the high L-DOPA contents reported in some mucuna cultivars, overconsumption of mucuna beans should be viewed with some caution until suitable processing methods are developed.  相似文献   

5.
《Food chemistry》1986,22(4):259-266
Defatted and undefatted seeds of papaya (Carica papaya) were analyzed for proximate composition, some toxicants, sugar composition, mineral content, physico-chemical properties of the seed oil and the fatty acid spectrum of the seed oil. The seed is a rich source of proteins (27·8% undefatted, 44·4% defatted), lipids (28·3% undefatted) and crude fibre (22·6% undefatted, 31·8% defatted). Of the toxicants estimated, glucosinolates occur in the highest proportion. The seed is low in free monosaccharides. Sucrose is the predominant sugar (75·0% of total sugars). Mineral content is generally low. However, Ca and P occur in appreciable quantities (17 340 μg/g and 10 250 μ/g, respectively). The seed oil is low in iodine value (74·8), free fatty acids (0·94%) and carotene (0·02 μg/g). The major fatty acid is C18:1 (79·1%).  相似文献   

6.
The composition, functional properties and structural features of the fiber from Rosa rubiginosa defatted seeds and from Gevuina avellana defatted and partially deproteinized seeds were evaluated. The effect of phosphate salts and temperature during the extraction of fibres and the influence of two drying technologies on the distribution of soluble and insoluble dietary fibre were assessed. The extraction of protein and monosaccharides was favoured by increasing temperature in the range studied. Water and oil absorption capacities higher than 10 g g?1 were observed for soluble and insoluble fibres from Gevuina avellana and for the soluble ones from Rosa rubiginosa. The insoluble fibre product from Rosa and Gevuina contained 650–810 g kg?1 and 390–440 g kg?1 neutral detergent fibre respectively. The protein content in the insoluble fibre varied in the range 100–150 g kg?1 and 120–260 g kg?1 and in the soluble fibre between 200–550 g kg?1 and 180–370 g kg?1 for Rosa and Gevuina respectively. Copyright © 2004 Society of Chemical Industry  相似文献   

7.
A direct comparison of two pre-treatments was undertaken to test their effect on the recovery of phenolic acids (PA) from three forage species. Samples of lucerne (Medicago sativa L), reed canarygrass (Phalaris arundinacea L), and switchgrass (Panicum virgatum L) were refluxed with 95% ethanol (EtOH) or neutral detergent solution (NDS). Subsequently, the resulting ethanol insoluble residue (EIR) and neutral detergent fibre (NDF) were treated with 1 M NaOH, and the extract was assayed for concentrations of p-coumaric acid (PCA) and ferulic acid (FA). In lucerne, the concentration of PCA was 9 times greater in the EIR than in the NDF (0·90 vs 0·11 mg g?1 dry matter, DM), and the FA concentration was 27 times greater in forage treated with EtOH than with NDS (1·89 vs 0·07 mg g?1 DM). In reed canarygrass (RCG), the concentrations of PCA and FA were slightly though significantly higher when the forage was pre-treated with EtOH. No significant differences in PA yield were detected between pre-treatments in switchgrass (SG). Extraction of EIR with hot EDTA (0·025 M , pH = 6·8) removed 80 to 90% of the total PA in EIR in lucerne but less than 5% of the PCA and FA in the grasses. These results indicate that almost all the PA in lucerne, in direct contrast to the grasses, are present in a fraction of the plant that is soluble in NDS. The relatively high PA concentration in the NDS soluble fraction suggests that the structure and composition of the fraction to which PA is esterified influence the degree to which PA affects digestibility.  相似文献   

8.
Green peas (Pisum sativum L) were harvested at three different time points—3 days apart—and subsequently sorted into four fractions according to seed size (diameter > 10.2 mm; 10.2–8.75 mm; 8.75–8.2 mm and 8.2–6.0 mm). Three varieties from two years were investigated. The study comprised a total of 31 green pea samples. The average protein content of the samples was 276 g kg?1 DM with relatively low variation (SE = 5.7). Protein content was highest in the smallest seeds. The average energy content was 18.6 MJ kg?1DM. Dietary fibre content was 226 g kg?1 DM, the major part (77%) as insoluble fibre. Seeds of early harvest and seeds with the smallest diameter had the lowest fibre (IDF and TDF) content and at the same time the highest energy digestibility. The average energy digestibility was 83.2%. Protein digestibility was relatively high (average 92.1%), while biological value (BV) and net protein utilisation (NPU) were moderate to low (60.6% and 55.8% respectively) due to low contents of the essential amino acids (g per 16 g N), especially tryptophan, methionine + cystine and lysine. Contents of lysine, tryptophan and methionine + cystine were more than 20% higher in the smallest seeds compared to the larger seeds. Similar differences were observed in seeds of late harvest as compared with seeds of early harvest. Correlation coefficients revealed a strong positive correlation between lysine, tryptophan and methionine + cystine content and the biological value of green pea protein. The three varieties investigated showed no differences in the chemical parameters although small differences in BV and NPU were observed.  相似文献   

9.
Prickly pear fruit seeds were subjected to a range of chemical analyses during their 15 week maturation period. Seeds contained on average 71.5 g kg?1 dry matter, 61.9 g kg?1 crude oil, 9.4 g kg?1 protein, 507.4 g kg?1 crude fibre, 12.3 g kg?1 ash and 409.0 g kg?1 carbohydrate. The fatty acid composition of prickly pear seed oil consisted of 1.3–1.9 g kg?1 myristic (14:0), 132.1–156.0 g kg?1 palmitic (16:0), 14.4–18.5 g kg?1 palmitoleic (16:1), 33.1–47.9 g kg?1 stearic (18:0), 210.5–256.0 g kg?1 oleic (18:1), 522.5–577.6 g kg?1 linoleic (18:2), 2.9–9.7 g kg?1 linolenic (18:3), 4.2–6.6 g kg?1 arachidic (20:0) and 2.1–3.0 g kg?1 behenic (22:0) acids, which is comparable with that of corn oil. No statistical difference in seed weight ratio was determined during the maturation period, whereas changes in the saturated fatty acids of the seed oil were observed. From this study it can be concluded that the seeds of prickly pear are suitable as animal feed. Copyright © 2003 Society of Chemical Industry  相似文献   

10.
Chia seeds were utilized by Aztecs as food and for medicinal purposes. Nowadays, this crop is gaining importance in many countries, due to its nutritional attributes. Some physical properties and chemical characteristics of chia seeds from four different regions of Mexico were evaluated and compared. Seed size distribution was not significantly affected (P > 0.05) by the region, with similar values of seed length (2.03–2.10 mm), width (1.27–1.32 mm), thickness (0.77–0.81 mm) and surface area (4.95–5.42 mm2). Bulk density (662–741 kg m?3), geometry and granulometric distribution were also determined. Origin of tested seeds significantly (P < 0.05) influenced their composition; all seeds had high contents of protein (18.5–22.3%), fat (21.5–32.7%) and fibre (20.1–36.1%). Chia seeds ratio between omega‐3 and omega‐6 fatty acids was 3:1 for the studied regions; seeds from Chiapas and Michoacán had the highest proportion of ω‐6 and ω‐3 fatty acids. The studied seeds contained phenolic compounds in the range of 0.53–0.71 mg GAE g?1.  相似文献   

11.
Dietary fibre, total polyphenols and phenolic acids in Spanish apples, peaches and pears were analysed and compared with their total radical‐trapping antioxidative potential (TRAP). There were no significant differences in the content of dietary fibre among the studied fruits. The content of total polyphenols was 2.4 ± 0.4, 2.1 ± 0.3 and 6.9 ± 0.7 g kg?1 in peeled fruits and 4.7 ± 0.4, 4.5 ± 0.4 and 11.1 ± 1.2 g kg?1 in their peels for peaches, pears and apples respectively. The contents of dietary fibre, total polyphenols, caffeic, p‐coumaric and ferulic acids and the TRAP values were significantly (P < 0.05) higher in peels than in peeled fruits. The contents of all studied compounds and the TRAP values were significantly higher in peeled apples and their peel than in peaches and pears. We observed a strong correlation between the contents of total polyphenols and phenolic acids and the total radical‐trapping antioxidative potential in all three fruits. The relatively high content of dietary fibre, the highest contents of total polyphenols, caffeic, p‐coumaric and ferulic acids and the highest value of TRAP make apples preferable among the studied fruits for dietary prevention of atherosclerosis and other diseases. © 2002 Society of Chemical Industry  相似文献   

12.
The proximate chemical composition of poppy seeds, along with minerals and water-soluble vitamins content was investigated. The compositions of the fatty acids and tocopherols of the extracted oil were also determined. The proximate analysis of poppy seeds showed the following composition: (440 g kg?1), protein (211 g kg?1), moisture (50 g kg?1), ash (63 g kg?1), crude fine (62 g kg?1) and total carbohydrates (236 g kg?1). Potassium and calcium were the predominant elements in the poppy seeds. Linoleic acid was the major unsaturated fatty acid (750 g kg?1 total fatty acids) while palmitic acid was the main saturated one (86-4 g kg?1). The amounts of α-, β- and δ-tocopherols found in poppy seed oil were 220 μg g?1, 40 μg g?1 and 20 μg g?1 respectively. Among the water-soluble vitamins determined, pantothenic acid was found at the highest level followed by niacin and thiamin.  相似文献   

13.
The protein, trypsin inhibitor and lipid of the seeds from 15 New Guinea and 15 Thai winged bean varieties grown in Malaysia were analysed. The results show that winged bean seeds have a high protein content, ranging from 27.8 to 47.2% (based on dry seed wt). The trypsin inhibitor contents vary from 1.6 to 3.6 million i.u. 100 g?1 of seeds; these trypsin inhibitor activities could be destroyed almost completely by a simple heat treatment. The oil content varies from 15.2 to 27.8% of the dry seed wt. Saturated fatty acids account for 31–37% of the total fatty acids and behenic acid (22:0) alone constitutes about 14–17% of the saturated fatty acid content. Unsaturated fatty acids account for 63–69% of total fatty acids; oleic and linoleic acids together constitute 57–64% of the unsaturated fatty acids.  相似文献   

14.
Commercial tomato canning yields two different byproducts. One is the material that results from peeling tomatoes, while the other results from removing the seeds. The peel byproduct contained 100.8 g protein, 256.4 g ash and 299.4 g acid detergent fiber kg?1. Ash content was high because the peel byproduct contained 83.8 g kg?1 sodium as a result of using a sodium hydroxide solution to peel the tomatoes. The seed byproduct contained 202.3 g protein, 51.8 g ash, and 537.9 g acid detergent fiber kg?1. An amino acid analysis of seeds indicated that approximately 60% of the protein results from amino acids. Both byproducts were analyzed for carotenoid content. The lycopene content of peel byproduct was 734 µg g?1 of dry material. Significant amounts of lutein, β‐carotene, and cis‐β‐carotene were also present. Seed byproduct contained 130 µg lycopene kg?1 of dry matter. The content of other carotenoids was approximately half of that present in the peels. Peel and seed byproducts were included at 75 g kg?1 in hen diets to determine the transfer of carotenoids to the yolk. When fed at this concentration, the lycopene content of dry egg yolk was approximately 0.9 µg g?1. Approximately 0.1% of the lycopene in peel byproduct and approximately 0.7% of the lycopene in the seed byproduct was transferred from the feed to the yolk. Lycopene appears more similar to carotene than to oxycarotenoids in its transfer to the yolk. Copyright © 2005 Society of Chemical Industry  相似文献   

15.
Two double low rapeseed varieties were separated into small and big seeds to study their nutritive value for broiler chickens. The seed weights for small and big seeds of spring rape variety Jaguar were 3.6 and 4.9 mg, and of winter rape Impala were 4.1 and 5.3 mg, respectively. Analytical results showed no significant differences in protein and fatty acid content between the big and small seeds. The small seeds contained more fibre constituents, eg lignin 13.7% higher for Jaguar and 3.4% higher for Impala, the other dietary fibre components show ed a similar trend. The big seeds, however, tended to be higher in fat and gross energy, but also in total glucosinolates. A 2 × 2 × 3 factorial design was performed on 24 broilers, to investigate the apparent digestibility and growth performance during three successive periods of balance trials, using diets consisting of 350 g kg?1 full-fat rapeseeds and 650 g kg?1 remainder feed mixture identical for all treatments. The diets with big seeds clearly showed higher digestibility for all measured dietary components. The surpluses as absolute percentage units respectively for dry matter were 2.8 (P < 0.001); gross energy 3.8 (P < 0.001); fat 7.9 (P < 0.001) and protein 1.6 (P = 0.045). The same trend was also found in the digestion of fatty acids and vitamin E. The big seeds displayed 7% higher (P = 0.071) growth rate and 8% higher (P = 0.002) feed conversion, respectively. Greater nutritional superiority of the big seeds was observed on the earlier growth ages, indicating the young birds are more sensitive to the seed size difference. It is concluded that the big seeds are more digestible than the small seeds and that a selection towards Digger seed size or a mechanical separation during processing will be beneficial.  相似文献   

16.
Abstract : An alkaloid-poor line of Washington lupin (Lupinus polyphyllus Lindl var SF/TA) was developed in an experiment started in 1982. The nutritive quality (alkaloid content, protein and amino acids, fat and fatty acids. macro- and micronutrients, fibre, sugars) yields, and seed quality of this line were studied. The results show that the total alkaloid content was low and varied in different seeds from 226 μg g?1 to 366 μg g?1 of dry matter. The main alkaloid was lupanine, but 16 other alkaloids (including sparteine and gramine) were also present. The var SF/TA cannot yet be used for human nutrition without processing although it would be a valuable protein crop. The results confirm that seeds which look different also vary in chemical composition.  相似文献   

17.
Seasonal changes in composition and properties of a high dietary fibre product from grapefruit peel were studied. Total dietary fibre decreased in January as compared to September (586–686 g kg-1). Main constituents from soluble fibre were: uronic acids (172–233 g kg-1), arabinose (13–41 g kg-1), galactose (4–11 g kg-1), glucose (5–10 g kg-1) and xylose (2–3 g kg-1). Insoluble dietary fibre (385–392 g kg-1) did not significantly change during the season. Its main constituents were: Klason lignin (29–37 g kg-1), uronic acids (33–70 g kg-1) and neutral sugars: glucose (149–196 g kg-1), mannose (45–50 g kg-1), xylose (25–38 g kg-1), galactose (20–22 g kg-1) and arabinose (16–45 g kg-1). Total neutral sugars from dietary fibre decreased over the harvest period (315–383 g kg-1) and an inverse trend was observed in total free-sugars from samples (49–85 g kg-1). Both, water holding capacity (7·0–9·3 g water g-1 dry sample) and glucose retardation index (7·0–25·3%) decreased from early stages in fruit development until late in the harvest season. Seasonal changes in grapefruit peel should be taken into account, in order to standardise the quality of rich fibre products. © 1997 SCI  相似文献   

18.
The chemical composition of the seed shell of the apricot (Prunus armeniaca) were investigated. Acid and neutral detergent fibres (ADF and NDF) and their fractions—hemicellulose, cellulose and lignin—were determined. The NDF content was about 920 g kg?1 DM. The concentrations of oils, soluble sugars, pectins, polyphenolic compounds, proteins and mineral elements were also determined. None of these fractions was present at levels higher than 25 g kg?1 DM. Essential amino acids comprised 38-41% of the total amino acids. Potassium (2.44 g kg?1) was the most abundant element, followed by calcium (1.15 g kg?1). Some possible applications for apricot seed shell are considered.  相似文献   

19.
Mimusops zeyheri, an indigenous tree widely distributed in sub‐Saharan Africa, provides edible fruit. Research on the tree has focused on fruit pulp composition and uses. This study evaluated the nutritional potential of M. zeyheri seed by determining the proximate, fibre and phytate‐phosphate content, the amino acid and fatty acid profiles and vitamin E content of the seed. Dry matter, organic matter, crude protein, ether extract and ash constituted 91.1%, 88.3%, 9.3%, 25.6% and 2.8% of the seed mass respectively. Glutamic acid (1.29 g per 100 g) was the most abundant amino acid. Lysine and phenylalanine were low. Calcium (587.4 mg per 100 g) was the most concentrated macro‐mineral assayed. Gross energy value was 24.34 MJ kg?1. Lipid yield was 21.3%. Oleic acid was the most abundant fatty acid. Vitamin E concentration was about 2 μg g?1. Phytate‐phosphate content was 0.03%. Neutral detergent fibre and acid detergent fibre constituted 33.2% and 15.3% respectively. M. zeyheri seed could be exploited as a dietary energy supplement and an oil source rich in oleic acid.  相似文献   

20.
Worldwide the USA is the largest user of flax fibre, though very little is actually grown or produced in the USA. ‘Ariane’ flax was grown in 1990–1991, 1991–1992 and 1998–1999 in South Carolina, USA and evaluated for production characteristics. Plots (15 m long and 2 m wide) in the fall of 1990 and 1991 generated dry matter plant yields ranging from 4510 (early harvest at a seeding rate of 67 kg ha?1) to 7340 (late harvest at a seeding rate of 134 kg ha?1) kg ha?1. Based on these results, seed was sown on a private farm using a drill in 19 cm rows at a seeding rate of 101 kg ha?1 in 1998–1999. Early harvest, selected for optimal fibre quality, produced a dry matter plant yield that averaged 4076 kg ha?1. Late harvest, selected to optimise seed plus fibre, produced a dry matter plant yield that averaged 5076 kg ha?1. Stubble remaining in the field after mowing at about 6.0–7.6 cm above the soil surface resulted in a fibre loss of about 3% of total plant dry matter or 10% of potential total fibre yield. Dry matter and fibre yields suggested that flax could be produced in the southeastern USA using traditional farming methods for the area. Copyright © 2004 Society of Chemical Industry  相似文献   

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