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1.
Phytic acid was determined in cereal (brans, flours and milled wheat-products) and breads. The method was based on complexometric titration of residual iron (III) after phytic acid precipitation. The cereal flours showed values ranged between 3–4 mg/g for soft wheats, 9 mg/g for hard wheat and 22 mg/g for whole wheat. Corn, millet and sorghum flours reported a mean of 10 mg/g and oat, rice, rye and barley between 4 and 7 mg/g. Wheat brans had wide ranges (25–58 mg/g). The phytic acid for oat brans was half that of wheat bran (20 mg/g) and higher value (58 mg/g) than that for rice bran. The milling products (semolinas) from hard wheat exhibited 10 mg/g and soft wheat a mean of 23 mg/g. The breads made with single or mixture cereal flours exhibited ranges between 1.5 and 7.5 mg/g. The loss of phytic acid relative to unprocessed flours was between 20% for oat bread and 50% for white bread.  相似文献   

2.
A combined dry and wet fractionation process is proposed to extract faba bean proteins with lower environmental impact. This fractionation process allowed to recover 87% of the total seeds proteins (92% of dehulled seeds proteins). This is achieved through the production of two protein concentrates (54 and 61% protein content w/w DM). After dry fractionation, wet extraction was performed on the protein-depleted fraction. The presented process consumed less energy and 5.5 times less water per kg extracted proteins, compared to traditional one-step wet extractions. Some anti-nutritional factors contents were also evaluated. Equivalent levels of phytic acid (about 11 mg/g), trypsin inhibitor activity (about 13 trypsin inhibition unit/g) and polyphenols (about 6 mg gallic acid equivalent/g) were observed in the 2 protein-rich fractions. These levels are mainly equivalent to those found after usual dry and wet one-step extractions. Significant differences of calcium, iron and zinc contents were observed between the 2 protein-rich fractions, causing a 30 to 50% difference between those fractions in terms of phytic acid/minerals ratio. Antinutritional factors content in the protein-rich fractions are equivalent to levels found in traditional legumes but still higher than existing recommendations.  相似文献   

3.
《Food chemistry》2001,74(4):437-441
This study determined the phytic acid content in the infant flour commonly consumed in the Canary Islands. A total of 400 samples from different cereals was analyzed. The method proposed by Garcı́a-Villanova et al. (1982) [Garcı́a-Villanova, R., Garcı́a-Villanova, R. J., Ruiz de Lope, C. (1982). Determination of phytic acid by complexometric titration of excess of iron (III). Analyst 107, 1503–1506] was the one used for determination of the phytic acid content in cereal flours. Phytic acid concentrations are within the range <1–⩾36 mg/g. The arithmetic mean obtained from all the samples studied is 24.6 mg/g. Most of the samples studied show a phytic acid content higher than 20 mg/g, and much lower values are observed in gluten-free flours (< 5 mg/g). Significant differences are observed for the different flour types. Gluten-free flour has a content lower than the rest; 9-cereal flour has a phytate concentration lower than the other flours tested but higher than gluten-free flour. Among wheat samples, phytate values are lower than in the varieties muesli-chocolate, 7-cereal, 8-cereal, multicereal and cereal-biscuit. Multicereal flour has a lower content than muesli-chocolate.  相似文献   

4.
《Food chemistry》2002,77(4):479-488
Supplementations of soy (full fat and defatted) and barley flours to wheat flours at 5, 10, 15 and 20% levels were carried out to test the effects on organoleptic and nutritional evaluation of the supplemented bread. Additions of 15% barley flour, 10% soy flour (full fat and defatted), 15% barley plus full fat soy flour and 15% barley plus defatted soy flour to wheat flour produced acceptable breads. However, substitution of soy (full fat and defatted) and barley flours to wheat flour separately and in combinations at 20% levels did not produce organoleptically acceptable bread. Various nutritional parameters, such as protein, fat, total lysine, protein digestibility (in vitro), sugars, starch digestibility (in vitro), total and available minerals, antinutrients, dietary fibre and β-glucan were determined in supplemented and control bread. Increasing the level of substitution from 5 to 10% of full fat and defatted soy flour to wheat flour significantly (P<0.05) increased protein (from 12.1 to 13.7 and 12.4 to 13.8%), lysine (from 2.74 to 3.02 and 2.76–3.05 mg/100 g protein) and total calcium (from 70.2 to 81.4 and 71.9–81.8 mg/100 g) contents. However, there was also an increase in phytic acid (238–260 and 233–253 mg/100 g), polyphenol (324–331 and 321–329 mg/100 g) and trypsin inhibitor activity (193–204 and 193–198 TIU/g). When barley flour was substituted separately, and in combinations, with full fat and defatted soy flour up to 15%, this significantly increased the contents of protein, total lysine, dietary fibre and β-glucan. It may be concluded that breads supplemented with barley and defatted soy flour, up to a 15% level, are organoleptically and nutritionally acceptable.  相似文献   

5.
探究大白芸豆、红芸豆、黑花芸豆、红腰豆和中白芸豆主要营养成分含量差异,对其营养品质进行分析与评价。以5个芸豆品种为试验材料,测定芸豆的蛋白质、脂肪、淀粉、灰分、矿物质元素、氨基酸和脂肪酸含量。结果表明:供试芸豆的蛋白质、脂肪、淀粉和灰分含量品种间差异极显著(P<0.01),其含量分别为17.30~23.70、1.10~1.90、34.90~38.30、4.00~4.80 g/100 g。中白芸豆蛋白质和淀粉含量最高,分别为23.70、38.30 g/100 g;黑花芸豆K、Ca、Na和Mg含量最高,分别为1.99×104、1.15×103、33.40、1.79×103 mg/kg,中白芸豆Fe和Zn含量最高,分别为77.10、41.80 mg/kg,中白芸豆Na含量最低,为25.40 mg/kg;氨基酸含量范围是0.08~3.75 g/100 g,中白芸豆必需氨基酸(EAA)、非必需氨基酸(NEAA)和总氨基酸(TAA)含量最高,分别为8.86、14.17、23.03 g/100 g;5种芸豆脂肪酸含量范围是0.0020~0.8913 g/100 g,含有16种脂肪酸,其中饱和脂肪酸有9种,单不饱和脂肪酸有3种,多不饱和脂肪酸有4种,其含量排序依次为多不饱和脂肪酸>饱和脂肪酸>单不饱和脂肪酸,大白芸豆脂肪酸含量最高,为2.02 g/100 g。中白芸豆多不饱和脂肪酸与饱和脂肪酸比率(PS)最低,数值为4.14,红腰豆动脉粥硬化指数(AI)值最低,数值为0.005。综合多种营养成分含量分析,中白芸豆营养品质优于大白芸豆、红芸豆、黑花芸豆、红腰豆。  相似文献   

6.
为降低绿豆芽菜中抗营养物质植酸含量,探究氯化盐对绿豆芽菜植酸降解的影响,研究了KCl、NaCl和CaCl2处理下绿豆芽菜的长势、植酸酶活性及植酸含量的变化,筛选了具有降植酸效果的氯化盐并优化了浓度组合。结果发现,NaCl和CaCl2能够促进植酸降解同时促进绿豆芽菜生长;单因素试验结果表明,1.6 mmol/L NaCl和6 mmol/L CaCl2降植酸效果最佳,且NaCl和CaCl2促进植酸降解作用有叠加效应。响应面法优化得到NaCl、CaCl2浓度分别为1.68 mmol/L和6.40 mmol/L时,植酸含量降低至8.04 μg/株,为对照的10.84%。  相似文献   

7.
We report on the impact of flour production from small- and large-seed varieties of broad bean on the quantitative and qualitative distribution of dietary fibre and starch. The experimental material consisted of the seeds of small-seed varieties of broad bean: Gobik and Goral, large-seed varieties of broad bean: Windsor Bialy and Bartom, and pea seeds of Albatros, Karat and Miko varieties (for comparison). The seeds were at full physiological maturity. Soaking and hydrothermal processing were shown to cause multidirectional, statistically significant changes in dietary fibre and starch, depending on both parameters of the process and type of the seeds. The flours of both small-seed broad bean varieties contained 20.15%-28.31%, flours of the large-seed broad bean 23.10%-27.50%, and those from pea seeds 20.13%-22.81% total dietary fibre. Attention should be paid to the considerable, approximately 2-fold increase in the soluble dietary fibre (SDF) content, compared to the raw material. The processing of seeds caused significant changes also with reference to starch. The most considerable changes were observed when the variant with the longest times of soaking (18 h) and heating (45 min) was applied. In the broad bean flours, the content of analytically available starch decreased by 22.94-30.60% and its digestibility was observed to decrease up to 30.25%. The pea flours, however, were characterised by an increased concentration of both forms of starch, especially significant for the digestible starch. The calculated content of resistant starch (RS) differentiated, to a high extent, the flours obtained. Under the same processing conditions, the flours of small-seed Gobik and Goral varieties of broad bean were characterised by a significantly higher RS content than those obtained from the large-seed varieties. A decrease in the starch digestibility rate index (SDRI) values, especially high for the small-seed varieties, should also be emphasised. The results obtained indicate that the nutritional value of flours can be determined by controlled processing parameters.  相似文献   

8.
The study was undertaken to determine the effect of various treatments, i.e. cooking after soaking, freezing after cooking and storage at a low temperature (-18°C, 21days), and autoclaving, of Polish cultivars of bean, pea and lentil seeds on the chemical composition and starch digestibility of the resultant flours. The cooking of seeds caused a significant decrease in contents of ash (by 11-48%), polyphenols (by 10-70%) and protein (to 19%) in flours made of bean. In addition, analyses demonstrated significantly decreased contents of resistant starch, RS (by 61-71%) and slowly digestible starch, SDS (by 56-84%). Storage of frozen seeds resulted in insignificant changes in the chemical composition, and in increased contents of both RS and SDS. The flours produced upon the autoclaving process were characterized by similar changes in the contents of ash and protein as in cooked seeds, yet losses of polyphenols were lower and, simultaneously, contents of RS and SDS were higher. All the analyzed flours were shown to be characterized by a reduced content of amylose in starch, which might have affected its digestibility. This was indicated by a strict negative correlation reported between the value of the starch digestion index (SDRI) and amylose content of starch (r=0.84, p>0.05).  相似文献   

9.
This study dealt with the effect of sourdough fermentation on antinutrients, phytochemicals, and antioxidant activities of flours from three Phaseoulus vulgaris L. genotypes with differing composition of lectins. Specifically, cultivar Lady Joy (LJ) devoid of phytohemagglutinin (PHA) and enriched in alfa‐amylase inhibitor (αAI), breeding line P500 low in PHA and devoid of αAI, and Taylor's horticultivar, containing normal levels of both proteins. Sourdough fermentation positively affects the nutritional values of all bean flours by reducing some antinutrients, for example, phytic acid while preserving αAI activity. It significantly increased total polyphenols, flavonols, and ascorbic acid content, while reducing flavonoids. No significant differences in antioxidant activity, measured by in vitro and ex vivo assays on human erythrocytes, were found. The kinetic profiles of conjugated dienes analysis showed a strong inhibitory effect on low‐density lipoproteins oxidation of all tested powders, with unfermented flours displaying the best antioxidant activity. Among bean powders, unfermented and fermented LJ showed the highest polyphenols level (4.21 ± 0.18 and 4.96 ± 0.15 mg GAE/g dw, respectively), oxygen radical absorbance capacity (ORAC) values (24.17 ± 0.14 and 24.02 ± 0.93 µmol TE/100g dw, respectively) and cellular antioxidant activity (71.6 ± 7.05 and 62.7 ± 3.3 units, respectively). Finally, since fermentation drastically reduces phytic acid content while preserving αAI activity, fermented LJ represents an important natural slimming supplement.  相似文献   

10.
The influence of yam bean hull on rat's mineral metabolism, serum composition and enzymatic activities was investigated. The chemical composition of the bean's hull shows a reasonably high crude protein (11.4%) but very low contents of crude fat (2.6%), phytic acid (82 mg/ 100 g) and phytin-phosphorus (23 mg/100 g). K and Ca are the major minerals present in yam bean hull. The hull, rich in cell wall polysac-charides, is composed of cellulose (35.4%), non-cellulose fractions made of pectin and hemicellulose put together (41.9%) and lignin (3.6%). The growth and feed conversion efficiency of rats fed yam bean hull diet were significantly better than rats fed pure cellulose and cellulose-free diets. Conversely, the metabolizable energy of yam bean hull diet (16.4 MJ/kg) was significantly (p < 0.05) lower than that of either cellulose-free (17.8 MJ/kg) or pure cellulose diet (17 MJ/kg). The retention of the minerals examined, except for Ca, was lower when the hull was included in diet as compared to the control (fibre-free) diet. The fibre containing diets decreased serum cholesterol, glutamic oxaloacetate transaminase (SGOT) and glutamic pyruvate transaminase (SGPT). Yam bean hull had no effect on packed cell volume and serum total protein.  相似文献   

11.
S. Yadav  N. Khetarpaul   《Food chemistry》1994,50(4):403-406
Indigenous fermentation of coarsely ground dehulled black-gram dhal slurry at 25, 30, and 35°C for 12 and 18 h reduced the levels of phytic acid and polyphenols significantly (P < 0·05). The unfermented legume batter had high amounts of phytic acid (1000 mg/100 g) and polyphenols (998 mg/100 g), and these were reduced to almost half in the product fermented at 35°C for 18 h. In-vitro digestibility of starch and protein improved significantly (P < 0·05) with increase in the temperature and period of fermentation. A significant (P < 0·01) and negative correlation found between the in-vitro digestibility and the anti-nutrient further strengthens these findings.  相似文献   

12.
African traditional weaning foods are usually prepared from starchy flours at a total solids content of 50–100 g l?1, giving a viscosity of 1000–3000 cP which is consumable by infants. These porridges have very low energy and nutrient densities. Processing to reduce the porridge viscosity and improve the energy and nutrient density may help in solving this problem. Maize, kidney bean and their 70:30 composite flours were irradiated at 0–10 kGy at room temperature. Irradiation greatly reduced the viscosity of porridges, probably by starch depolymerisation. Irradiation improved the starch digestibility of raw bean flours, possibly either by inhibiting α‐amylase inhibitors or by weakening the thick cell walls that enclose the starch granules, thus improving accessibility to enzymes. However, in raw maize, cooked maize and cooked bean flours there was maximum starch digestibility at a dose of 2.5 kGy, followed by small but significant decreases in starch digestibility at higher doses, more so in maize than in bean flours. The decrease in digestibility could be due to the formation of inhibitors of amylolytic enzymes (Maillard reactions products) or to the formation of resistant starch. Irradiation doses required to increase the total solids content of traditional maize‐ and/or bean‐based weaning porridges to at least 200 g l?1 do not compromise starch digestibility significantly. © 2001 Society of Chemical Industry  相似文献   

13.
Detoxification of apricot kernels by soaking in distilled water and ammonium hydroxide for 30 h at 47 °C decreased the total protein, non-protein nitrogen, total ash, glucose, sucrose, minerals, non-essential amino acids, polar amino acids, acidic amino acids, aromatic amino acids, antinutritional factors, hydrocyanic acid, tannins and phytic acid. On the other hand, removal of toxic and bitter compounds from apricot kernels increased the relative content of crude fibre, starch, total essential amino acids. Higher in-vitro protein digestibility and biological value was also observed. Generally, the detoxified apricot kernels were nutritionally well balanced. Utilization and incorporation of detoxified apricot kernel flours in food products is completely safe from the toxicity point of view.  相似文献   

14.
Eight Navy bean samples, roasted between 92 and 125°C in a particle-to-particle heat exchanger, were ground to produce whole bean and hull flours. Dehulled bean flours were also separated into high protein (HPF) and high-starch fractions (HSF) by air classification. Whole bean flours contained 1.92% fat and 25.8% protein on the average. Hull flours contained between 31.2 and 50.2% dietary fiber, of which approximately 60% was crude fiber. Dehulled bean flour containing 26.8% protein was fractionated into HSF and HPF with average protein contents of 15.6 and 43.1%, respectively. Greater protein shift may be further accomplished by finer grinding and adjustment of the cut point. Residual trypsin inhibitor activity of HPF s ranged from 25–108 TIA/mg protein, down from 116 units in the raw control HPF. Hemagglutinins were inactivated from 110 HA units/mg to values ranging from 2.4–105 HA units/mg.  相似文献   

15.
Whole grain flour is used most often as raw material for fuel alcohol production. However, the dry-milling process and the non-starch components of flours may impact the enzymatic hydrolysis of starch to glucose. The particle size distributions of flours prepared from whole grain triticale, barley, wheat and corn were determined and the effects of pre-washing with water, hexane, 100% ethanol or 50% ethanol on flour composition and the amylolysis of starch were studied. Scanning electron microscopy of the flours revealed that grinding grain to pass a sieve with an aperture size of 0.5 mm effectively released starch granules from endosperm cells. Pre-washing with water or 50% ethanol decreased the protein, phytic acid and total free phenolic contents of flours and, except for corn flour, increased starch content. Pre-washing with water reduced the ash contents of all flours, and reduced the ??-glucan content of barley flour by 98%. Pre-washing with hexane or 100% ethanol removed much of the lipid from the flours. Pentosan content was affected only slightly by any of the pre-washing treatments. Each of the pre-washings was associated with a significant change, positive or negative, in the extent of ??-amylolysis for one or more of the flours. The degree of ??-amylolysis in unwashed flours ranged from 22.4 to 26.1%, and from 21.6 to 28.1% in pre-washed flours, varying with flour source and solvent treatment. Pre-washing of flours increased the degree of hydrolysis achieved with sequential ??-amylase/amyloglucosidase treatment, with values ranging from 61.4 to 72.8% in pre-washed flours compared to 56.2-57.8% in unwashed flours. The highest degrees of hydrolysis were achieved with 50% ethanol pre-washing (72.4 and 72.8% for triticale and barley flours, respectively). The degree of ??-amylase/amyloglucosidase hydrolysis obtained for isolated starches ranged from 83.7 to 93.0%. This study demonstrated clearly that the partial removal of non-starch components from whole grain flours by solvent pre-washing enhanced the degree of amylolysis of starch.  相似文献   

16.
《Food chemistry》2005,91(2):327-331
Thermal heat processing effects were investigated on antinutrients, protein and, starch digestibility of black grams, chick peas, lentils, red and white kidney beans. The tannin and phytic acid contents in these five food legumes ranged from 770–1100 mg/100 g to 970–1440 mg/100 g, respectively, whereas protein and starch digestibilities of the raw food legumes were 33.0–37.6% and 36.8–42.0%, respectively. Reduction in the levels of antinutrients, along with an improvement in protein and starch digestibility, was observed after cooking these food legumes. Antinutrient, including tannin (33.1–45.7%) and phytic acid (28.0–51.6%) contents, were reduced by different thermal heat treatments (121AC10, 121AC20, 121AC40, 121AC60, 121AC90, 128AC20). Maximum improvement in protein (95.7–105%) and starch (117–138%) digestibilities was observed on cooking these food legumes at 121 °C for 10 min (121AC10). However, ordinary cooking resulted in improvement of protein and starch digestibilities of the food legumes by 86.0–93.3% and 84.0–90.4%, respectively.  相似文献   

17.
Flours from six legume species (lentil, lima bean, field pea, chickpea, fababean, mung bean) were devoid of α-amylase inhibitory activity but five biotypes of Phaseolus vulgaris showed activities of 27 to 40 units/mg protein. Air classification of the pin milled flours yielded fine fractions which contained 37% (black bean) to 61% (navy bean) protein and 38 to 66 units of inhibitor activity/mg protein, respectively. The coarse starch fractions were proportionately depleted in protein content and inhibitor activity. The partially purified amylase inhibitor from navy bean was active towards porcine pancreatic α amylase. The optimum pH for inhibition was 5.6 - 5.7, with the inhibitor being most stable at pH 6.9 after 4 h incubation at 37°C. The inhibition was faster at 37°C than at 25°C. Although retaining most of its inhibitory power between 37°C–60°C, the navy bean inhibitor showed a complete loss of activity after 20min at 90°C.  相似文献   

18.
Legume seeds (soy bean, lupin and bean seeds) were soaked in 0.5% sodium bicarbonate in attempt to evaluate their nutritional quality and protein solubility index. Soaking process led to an increase in the hydration coefficient, seed weight, total protein, ash, fat, fiber, while non protein nitrogen, total carbohydrates, starch, stachyose, raffinose, reducing sugars, and minerals (except Na) were decreased. All antinutritional factors such as phytic acid, tannin, trypsin inhibitor and hemagglutinin activity were decreased during soaking in 0.5% sodium bicarbonate; it was the same for the protein solubility in different solutions, while the in-vitro protein digestibility and available lysine were increased.  相似文献   

19.
ABSTRACT: The biochemical and functional properties of 2 hard-to-cook common bean cultivars (Phaseolus vulgaris, L.) were investigated after the extrusion process. Beans of BRS pontal and BRS grafite cultivars were milled and extruded at 150 °C, with a compression ratio screw of 3 : 1, 5-mm die, and screw speed of 150 rpm. Extrudate flours were evaluated for water solubility (WS), water absorption index (WAI), oil absorption capacity (OAC), foaming capacity (FC), emulsifying activity (EA), antinutritional factors, and in vitro protein and starch digestibility. Results indicated that the extrusion significantly decreased antinutrients such as phytic acid, lectin, α-amylase, and trypsin inhibitors, reduced the emulsifying capacity and eliminated the FC in both BRS pontal and BRS grafite cultivars. In addition, the WS, WAI, and in vitro protein and starch digestibility were improved by the extrusion process. These results indicate that it is possible to produce new extruded products with good functional and biochemical properties from these common bean cultivars.  相似文献   

20.
N. Wang  D.W. Hatcher  R. Toews  E.J. Gawalko 《LWT》2009,42(4):842-848
The effect of cooking and dehulling on nutrients and anti-nutritional factors of several varieties of lentils (Lens culinaris) was investigated. Significant (p < 0.05) variations existed among the lentil varieties with respect to their crude protein, starch, ash, soluble dietary fiber (SDF), insoluble dietary fiber (IDF), total dietary fiber (TDF), resistant starch (RS), trypsin inhibitor activity (TIA), minerals, phytic acid, tannins, sucrose and oligosaccharides (raffinose, stachyose and verbascose) content. Cooking lentils in boiling water significantly increased protein, starch, IDF, TDF, resistant starch, Ca, Cu and Mn content, whereas reduced ash, Fe, K, Mg, P, Zn, TIA, phytic acid, tannins, sucrose and oligosaccharides were observed. Dehulling (removal of seed coat) resulted in a significant increase in protein, starch, resistant starch, K, P, phytic acid, stachyose and verbascose content, however, a significant decrease in SDF, IDF, TDF, Ca, Cu, Fe, Mg, Mn and tannin content was observed.  相似文献   

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