首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 46 毫秒
1.
The effect of different conditions of pea germination on dietary fiber (DF) composition was studied. Insoluble dietary fiber (IDF) and soluble dietary fiber (SDF) were subjected to acid hydrolysis, and the resultant neutral sugars, uronic acids, and Klason lignin were quantified. Germinated peas exhibited significantly higher contents of total dietary fiber (TDF) than the raw sample, due to the increases of both DF fractions. Under darkness conditions, germination exhibited the highest contents of IDF and SDF. Decreasing IDF/SDF ratios showed that the carbohydrate changes did not take place to the same extent during germination, the SDF fraction being the most affected. The detailed chemical composition of fiber fractions reveals increases of cellulose in the IDF of germinated samples, whereas SDF exhibits a decrease of pectic polysaccharides and also increases of polysaccharides rich in glucose and mannose. The DF results were corroborated by a comparative examination of the cell wall carbohydrate composition.  相似文献   

2.
The proximate composition of sclerotia of Pleurotus tuber-regium, Polyporus rhinoceros, and Wolfiporia cocos, together with the yield, purity, monosaccharide profile, and microstructure of their insoluble dietary fiber (IDF) and soluble dietary fiber (SDF) fractions prepared from AOAC enzymatic-gravimetric methods were investigated and compared. All three sclerotia were typical carbohydrate rich sclerotia [ranging from 90.5 to 98.1% dry matter (DM)] with an exceptionally low amount of crude lipid content (ranging from 0.02 to 0.14% DM). Besides, all three sclerotia possessed substantial amounts of IDF (ranging from 77.4 to 94.6% DM) with notably high levels of nonstarch polysaccharides (NSP) (89.9-92.2% DM) in which glucose was the predominant sugar residue (90.6-97.2% of NSP DM). On the contrary, both the yield (only ranging from 1.45 to 2.50% DM) and the amount of NSP (ranging from 22.4 to 29.6% DM) of the three sclerotial SDF fractions were very low. Scanning electron micrographs showed fragments of interwoven hyphae and insoluble materials in the three sclerotial IDF fractions, but only an amorphous structure of soluble materials was observed in the SDF fractions. The potential use of these fiber preparations was discussed.  相似文献   

3.
Onion tissues of three varieties were evaluated for dietary fiber (DF) composition. Insoluble (IDF) and soluble (SDF) dietary fibers were subjected to acid hydrolysis, and the resultant neutral sugars, uronic acids, and Klason lignin were quantified. Brown skin exhibited the highest total dietary fiber (TDF) content (65.8%) on a dry matter basis, followed by top (48.5%) and bottom (38.6%), IDF being the main fraction found. The SDF:IDF ratio decreased from inner to outer tissues. Brown skin and outer leaves byproducts appear to be the most suitable sources of DF that might be used in food product supplementation. The chemical composition reveals that cellulose and pectic polysaccharides were the main components of onion DF in all tissues, although differences between them were noticed. An increase in the uronic acids/neutral sugars ratio from inner to outer tissues was found, suggesting that the galactan side chain shows a DF solubilization role.  相似文献   

4.
The effect of fermentation on antinutritional factors and also on total dietary fiber (TDF), insoluble (IDF) and soluble (SDF) dietary fiber fractions was studied in beans (Phaseolus vulgaris L.). The processes studied were two types of fermentation (lactic acid and natural), and a portion of the obtained flours were processed by autoclaving. The dietary fiber (DF) content and its components were determined using the enzymatic-gravimetric and enzymatic-chemical methods. The TDF content ranged from 24.5% dry matter (DM) in the raw to 25.2% DM in the processed beans. All the processing treatments significantly decreased the SDF content, and irrelevant changes were noticed in the IDF content of processed beans. Cellulose content of all samples was reduced by the processing treatments. Correspondingly, higher amounts of resistant starch was observed in the processed beans, except in the lactic acid fermented ones. However, the levels of pectic polysaccharides and Klason lignin were higher in the samples fermented by Lactobacillus plantarum. The action of microorganisms was determinant for the different degradation of the bean cell wall, disrupting the protein-carbohydrate integration, thus reducing the solubility of DF.  相似文献   

5.
A collaborative study was conducted to determine the insoluble dietary fiber (IDF), soluble dietary fiber (SDF), and total dietary fiber (TDF) content of food and food products by using a combination of enzymatic and gravimetric procedures. The method was basically the same as that developed for TDF only, which was adopted official final action by AOAC, except for changing the concentration of buffer and base and substituting hydrochloric acid for phosphoric acid. These changes were made to improve the robustness of the method. Duplicate blind samples of soy isolate, white wheat flour, rye bread, potatoes, rice, corn bran, oats, Fabulous Fiber, wheat bran, and a high fiber cereal were analyzed by 13 collaborators. Dietary fiber values (IDF, SDF, and TDF) were calculated as the weight of residue minus the weight of protein and ash. The coefficients of variation (CVs) of both the independent TDF determination and the sum of IDF and SDF were better than 15 and 18%, respectively, with the exception of rice and soy isolate. These 2 foods, however, contained only about 1% TDF. The CVs of the IDF were equally good, except for Fabulous Fiber, for which filtration problems occurred. The CVs for the SDF were somewhat high, but these products had very low SDF content. There was excellent agreement between the TDF determined independently and the TDF determined by summing the IDF and SDF. The method for separate determination of IDF and SDF requires further study. The modifications (changes in concentration of buffer and base and the use of hydrochloric acid instead of phosphoric acid) to the official final action method for TDF have been adopted.  相似文献   

6.
A simple method for the isolation and purification of alpha-galactosides, raffinose family oligosaccharides (RFOs), from legumes has been developed. The method includes (i) imbibition of seeds, (ii) extraction with 50% ethanol, (iii) precipitation of RFOs, (iv) purification of RFOs on diatomaceous earth and charcoal, and (v) cation-exchange chromatography. The described method allows one to obtain high purity RFO preparations (90% for lentil and 80% for pea seeds, determined by HPLC-RI analysis) in the form of white, fine powder. Yields of alpha-galactosides isolated from 100 g of seeds of lentil and pea were 5.6 and 4.3 g, respectively.  相似文献   

7.
Nutritionists recommend increasing the intake of soluble dietary fiber (SDF), which is very low in most cereal-based products. Conversion of insoluble DF (IDF) into SDF can be achieved by chemical treatments, but this affects the sensorial properties of the products. In this study, the possibility of getting a substantial increase of SDF from cereal products using a tailored preparation of Trichoderma enzymes is reported. Enzymes were produced cultivating Trichoderma using durum wheat fiber (DWF) and barley spent grain (BSG) as unique carbon sources. Many Trichoderma strains were screened, and the hydrolysis conditions able to increase by enzymatic treatment the amount of SDF in DWF and BSG were determined. Results demonstrate in both products that it is possible to triple the amount of SDF without a marked decrease of total DF. The enzymatic treatment also causes the release of hydroxycinnamic acids, mainly ferulic acid, that are linked to the polysaccharides chains. This increases the free phenolic concentration, the water-soluble antioxidant activity, and, in turn, the phenol compounds bioavailability.  相似文献   

8.
This study was undertaken to evaluate the lipidemic response of rice bran and the possible enhancement of its healthful properties by using raw or processed white or brown rice in place of corn starch. All diets contained 10% total dietary fiber, 15% fat, and 0.5% cholesterol. Weanling male golden Syrian hamsters were fed cellulose control (CC), processed corn starch (PCS), cellulose with processed brown rice (CPBR), rice bran (RB), RB with white rice (RBWR), RB with processed white rice (RBPWR), RB with brown rice (RBBR), and RB with processed brown rice (RBPBR) diets. After three weeks, the PCS diet significantly lowered total plasma cholesterol (TC) compared with the CC, CPBR, RBWR, and RBPBR diets. RB and RBBR diets significantly lowered TC and LDL‐C compared with CPBR diet. All the RB‐containing and PCS diets significantly lowered liver cholesterol and liver lipid content. Processing white rice increased TDF content 240% and insoluble dietary fiber (IDF) 360%, whereas soluble dietary fiber (SDF) decreased by 25%. Uncooked brown rice contained 7 times as much TDF as uncooked white rice. Processing brown rice decreased its TDF, IDF and SDF contents by 12, 6, and 42%, respectively. The data suggest that a possible mechanism for cholesterol‐lowering by rice bran, with or without added raw or processed rice (white or brown), is by decreasing lipid digestibility and increasing neutral sterol excretion, whereas cholesterol‐lowering by processed corn starch is mediated through other mechanisms.  相似文献   

9.
提高大豆渣膳食纤维中可溶性成分的方法研究   总被引：2，自引：2，他引：2  
以大豆渣为原料，采用微生物发酵、微射流均质机高压均质处理和高温蒸煮的方法来提高大豆膳食纤维中可溶性成分含量，研究不同发酵时间、不同处理压力和蒸煮温度以及蒸煮时间对提高豆渣可溶性膳食纤维（SDF）含量的影响。结果表明：利用发酵法可提高可溶性膳食纤维的含量达15%之多，并且在发酵的前6天，SDF含量增长很快，6 d后SDF的含量变化较少；而高压均质处理法提高可溶性膳食纤维含量的幅度在10%～28%之间，并随着处理压力的升高而增大；高温蒸煮法能提高可溶性膳食纤维的含量20%，121℃，20 min为较理想的蒸煮条件。  相似文献   

10.
为明确玉米籽粒营养成分的分布差异及不同部位富集特征,应用快速缓苏、微量着水半湿法分层破胚剥皮技术,结合靶向代谢组学方法,对郑单958玉米不同部位的营养成分及基础代谢物质进行分析与比较。结果表明玉米籽粒不同部位的淀粉、脂肪、矿物元素和膳食纤维等营养物质含量存在显著差异（P<0.05）。该研究中的玉米内皮层可能主要由种皮、糊粉层及部分外胚乳构成,该部位营养成分的种类及含量均较为丰富,其中水溶性膳食纤维含量显著高于其他部位（P<0.05）,可作为玉米水溶性膳食纤维的提取分离来源。K、P和Mg元素是玉米中含量最高的矿物元素,主要存在于胚芽中,Fe、Zn、Mn和Cu元素在胚芽和玉米皮层中均有较多分布,精制加工会导致这些矿物元素的损失。玉米胚芽中水解氨基酸种类较其他部位丰富且含量较高（P<0.05）,甜味氨基酸占总游离氨基酸含量的24.49%,高于玉米皮层部位、显著高于胚乳部位。研究结果为玉米营养健康食品的创制、玉米精深加工及相关专用装备的研发提供参考。  相似文献   

11.
Methods were developed to efficiently isolate legume cotyledon fibers with relatively high yields and purities. Seeds of pea (Pisum sativum), chickpea (Cicer arientinum), and lentil (Lens culinaris) were roller milled into flour and fractionated into prime starch, tailings starch, and water solubles. Insoluble dietary fiber was isolated from tailings starch by wet screening on sieves with openings ranging from 53 to 90 μm. Yield of insoluble fiber using a sieve with 53‐μm openings ranged from 49.7 to 59.2% of insoluble fiber in flour with purities ranging from 85.5 to 87.3%. Soluble dietary fiber was isolated from the water‐soluble fraction following acid precipitation of soluble protein at pH 4. Soluble fiber yield ranged from 83.3 to 89.6% of flour soluble fiber with purities ranging from 64.5 to 70.6%. Glucose was the most common sugar component of hulls and soluble cotyledon fibers, while arabinose was the main sugar in insoluble fibers. Insoluble fiber exhibited significantly higher swelling capacities and water and oil binding capacities in comparison to hulls and soluble cotyledon fibers. Apparent viscosities of soluble cotyledon fibers ranged from 3.13 to 3.43 Pa•sec and exhibited Newtonian characteristics.  相似文献   

12.
Pigeon pea (Cajanus cajan var. aroíto) seeds were fermented in order to remove antinutritional factors and to obtain functional legume flour to be used as pasta ingredients. Fermentation brought about a drastic reduction of alpha-galactosides (82%), phytic acid (48%), and trypsin inhibitor activity (39%). Fermented legume flours presented a notable increase of fat and total soluble available carbohydrates, a slight decrease of protein, dietary fiber, calcium, vitamin B2, vitamin E, and total antioxidant capacity, and a decrease of soluble dietary fiber, Na, K, Mg, and Zn contents. No changes were observed in the level of starch and tannins as a consequence of fermentation. The fermented flour was used as an ingredient to make pasta products in a proportion of 5, 10, and 12%. The supplemented pasta products obtained had longer cooking times, higher cooking water absorptions, higher cooking loss, and higher protein loss in water than control pasta (100% semolina). From sensory evaluations, fortified pasta with 5 and 10% fermented pigeon pea flour had an acceptability score similar to control pasta. Pasta supplemented with 10% fermented pigeon pea flour presented higher levels of protein, fat, dietary fiber, mineral, vitamin E, and Trolox equivalent antioxidant capacity than 100% semolina pasta and similar vitamins B1 and B2 contents. Protein efficiency ratios and true protein digestibility improved (73 and 6%, respectively) after supplementation with 10% fermented pigeon pea flour; therefore, the nutritional value was enhanced.  相似文献   

13.
Fiber-rich fractions (FRFs) including soluble and insoluble dietary fibers (SDF and IDF), alcohol-insoluble solid (AIS), and water-insoluble solid (WIS) were isolated from the peel of Citrus sinensis L. cv. Liucheng for analysis and tests. The peel was rich in insoluble FRFs (IDF, AIS, and WIS; 476-515 g kg(-1) of peel), which were mainly composed of pectic substances and cellulose, and also contained pectic polysaccharide-rich SDF (94.1 g kg(-1) of peel). These insoluble FRFs had water-holding capacities (15.5-16.7 mL g(-1)), oil-holding capacities (2.35-5.09 g g(-1)), cation-exchange capacities (454-997 mequiv kg(-1)), and swelling properties (14.6-21.1 mL g(-1)) much higher than those of cellulose. These results recommended the consumption of these peel insoluble FRFs of desired physicochemical properties as sources of food fibers or low-calorie bulk ingredients in food applications requiring oil and moisture retention. Further investigations on the physiological functions of these peel FRFs using animal-feeding experiments are underway.  相似文献   

14.
《Journal of plant nutrition》2013,36(4-5):727-741
The yield and zinc (Zn) content response of faba bean (Vicia faba L.), chickpea (Cicer arietinum L.), lentil (Lens culinaris Medik.) and wheat (Triticum aestivum L.) to applications of Zn fertilizer was compared in a glasshouse experiment using two alkaline soils from southwestern Australia. Comparative Zn requirements were determined from yields of 46-day-old dried shoots when no Zn fertilizer was applied, the amount of Zn required to produce the same percentage of the maximum (relative) yield of dried shoots, and the Zn content of dried shoots (Zn concentration multiplied by yield of dried shoots). The concentration of Zn in youngest tissue and in dried shoots was used to determine critical concentrations for Zn in tissue. Faba bean used indigenous soil Zn more effectively than chickpea, followed by wheat and then lentil. The Zn requirement was lowest for faba bean, and increased in the order faba bean < chickpea < wheat < lentil. Zinc concentration in dried youngest tissue and in dried shoots increased with an increase in the amount of added Zn. The critical Zn concentration in the youngest tissue, associated with 90% of the relative yield, was (mg Zn kg?1): 25 for lentil, 18 for faba bean, 17 for chickpea and 12 for wheat; corresponding values for dried whole tops (mg Zn kg?1) were: 30 for lentil, 19 for faba bean, 17 for chickpea, and 20 for wheat. Information on comparative responses of the grain legumes to Zn additions relative to wheat, and critical tissue test values, will aid in the fertilizer management of Zn in cool-season grain legumes in the southwestern Australian farming systems.  相似文献   

15.
The objective of this study was to evaluate the chemical, physicochemical, and functional properties of agrowastes derived from okara ( Glycine max), corn cob ( Zea mays sp.), wheat straw ( Triticum sp.), and rice husk ( Oryza sativa) for potential applications in foods. The fibrous materials (FM) were treated with alkali to yield fibrous residues (FR). Rice husk contained the highest ash content (FM, 8.56%; FR, 9.04%) and lowest lightness in color (FM, 67.63; FR, 63.46), possibly due to the abundance of mineral constituents. Corn cob contained the highest amount of soluble dietary fiber (SDF), whereas okara had the highest total dietary fiber (TDF). The high dietary fiber fractions of corn cob and okara also contributed to the highest water- and oil-holding capacities, emulsifying activities, and emulsion stabilities for both FM and FR samples. These results indicate that these agrowastes could be utilized as functional ingredients in foods.  相似文献   

16.
Acacia seed is a promising famine food due to its ability to thrive in dry zones of the world. In this study, some chemical compounds of nutritional importance as well as starch hydrolysis in three cultivars of Acacia tumida and A. colei were determined. The crude protein was 20.6–23.0%, while extractable protein was 11.5–17.5%. Total dietary fiber (TDF) (28.5–32.7%) and soluble dietary fiber (SDF) (2.2–5.8%) were higher than values reported for most legumes. Reducing sugar range was 31.0–54.5 mg/g, while total sugar range was 137–161 mg/g. The starch content of the seed was 25.6–32.3%. The samples did not contain any alkaloid but did contain saponins. Phytate and trypsin inhibitor contents were low; oxalate was fairly high (2.2–2.6 g/100 g), but tannin was on the high side 66.0–86.7 mg/g) compared with legumes. In vitro starch digestibility was highest in A. tumida (III). Using a first‐order kinetic equation, A. colei showed the highest initial rate of starch hydrolysis (t1/2 = 411.56 and 1,893.4 min), followed by A. tumida (III) (539.25 and 1,738.1 min); the lowest vales were for A. tumida (II) (1,764.99 and 4,249.8 min) for both methods of starch digestion.  相似文献   

17.
《Cereal Chemistry》2017,94(3):524-531
The aim of this study was to characterize the physicochemical, functional, and digestion properties of bagasses derived from broad beans, chickpeas, lentils, and white beans, and to isolate the starch and a fiber‐rich fraction that can be used as a food ingredient. The bagasses showed different chemical compositions that were related to their botanical origin. The further processing that involved mechanical separation of starch yielded up to 69.65% with ≥80.12% recovery and high purity (≥94.42%), and a fiber‐rich fraction (total dietary fiber content ≥72.75%) in which the majority was insoluble fiber. The starch digestion fractions of the isolated lentil starch showed the highest amount of slowly digestible starch (30.76%), whereas the white bean contained the highest resistant starch content (15.65%). All starches showed predicted glycemic indexes ≤ 66.90, which classify them as medium glycemic foods. In vitro protein digestion was higher for the bagasse fraction (up to 89.78%), followed by the fiber‐rich fraction (84.36%). This research demonstrates that it is possible to revalorize the use of pulses bagasse, which could contribute to enhance the technological and economic output of the protein isolation process, rendering two potentially functional fractions.  相似文献   

18.
The in vitro bile acid binding by rice bran, oat bran, dehulled barley, and β‐glucan enriched barley was determined using a mixture of bile acids at a duodenal physiological pH of 6.3. Six treatments and two blank incubations were conducted testing substrates on an equal protein basis. The relative in vitro bile acid binding of the cereal brans on an equal total dietary fiber (TDF) and insoluble dietary fiber (IDF) basis considering cholestyramine as 100% bound was rice bran 45 and 49%; oat bran 23 and 30%; dehulled barley 33 and 57%; and β‐glucan enriched barley 20 and 40%, respectively. Bile acid bindings on equal protein basis for the respective cereals were 68, 26, 41, and 49%. Bile acid binding by rice bran may account to a great extent for its cholesterol‐lowering properties, while bile acid binding by oat bran suggests that the primary mechanism of cholesterol lowering by oat bran is not due to the bile acid binding by its soluble fiber. Bile acid binding was not proportional to the soluble fiber content of the cereal brans tested. Except for dehulled barley, bile acid binding for rice bran, oat bran, and β‐glucan enriched barley appear to be related to their IDF content. Highest relative bile acid binding values for rice bran and β‐glucan enriched barley were observed on an equal protein basis, whereas highest values for dehulled barley were based on IDF. Data suggest that of all four cereals tested, bile acid binding may be related to IDF or protein anionic, cationic, physical and chemical structure, composition, metabolites, or their interaction with active binding sites.  相似文献   

19.
Pulse starches were isolated from different cultivars of pea, lentil, and chickpea grown in Canada under identical environmental conditions. The in vitro digestibility and physicochemical properties were investigated and the correlations between the physicochemical properties and starch digestibility were determined. Pulse starch granules were irregularly shaped, ranging from oval to round. The amylose content was 34.9–39.0%. The amount of short A chains (DP 6‐12) of chickpea starch was much higher than the other pulse starches, but the proportions of B1 and B2 chains (DP 13‐24 and DP 25‐36, respectively) were lower. The X‐ray pattern of all starches was of the C type. The relative crystallinity of lentil (26.2–28.3%) was higher than that of pea (24.4–25.5%) and chickpea starches (23.0–24.8%). The swelling factor (SF) in the temperature range 60–90°C followed the order of lentil ≈ chickpea > pea. The extent of amylose leaching (AML) at 60°C followed the order of pea ≈ chickpea > lentil. However, in the temperature range 70–90°C, AML followed the order of lentil > pea > chickpea. The gelatinization temperatures followed the order of lentil > pea > chickpea. The peak viscosity, setback, and final viscosity of pea starch were lower than those of the other starches. Lentil starch exhibited lower rapidly digestible starch (RDS) content, hydrolysis rate, and expected glycemic index (eGI). The resistant starch (RS) content of both lentil cultivars was nearly similar. However, pea and chickpea cultivars exhibited wide variations in their RS content. Digestibility of the pulse starches were significantly correlated (P < 0.05) with swelling factor (60°C), amylose leaching (60°C), gelatinization temperature, gelatinization enthalpy, relative crystallinity, and chain length distribution of amylopectin (A, B1, and B2 chains).  相似文献   

20.
Abstract

The copper (Cu) requirement of four crop species was measured in a glasshouse experiment using yield of dried shoots and Cu content (Cu concentration multiplied by yield of dried shoots) of 62 day old plants grown in two different alkaline soils. The species compared were faba bean (Vicia faba L. cv. Fiord), chickpea (Cicer arietinum L. cv. Tyson), lentil (Lens culinaris Medik cv. Digger), and spring wheat (Triticum aestivum L. cv. Stretton). The comparative Cu requirement of the species was determined from yields of dried shoots when no Cu fertilizer was applied, the amount of applied Cu required to produce the same percentage of the maximum (relative) yield of dried shoots, and the Cu content of dried shoots. The concentration of Cu in youngest tissue and in dried shoots was used to determine critical concentrations of Cu in tissue associated with 90% of the maximum yield. Faba bean used indigenous soil Cu more effectively than wheat, followed by chickpea and then lentil. As measured using both shoot yield and Cu content in shoots, the Cu requirement was lowest for faba bean, and increased in the order faba bean < wheat < chickpea < lentil. Copper concentration in dried youngest tissue and in dried shoots increased with an increase in the amount of added Cu. The critical Cu concentration in the youngest tissue was (mg Cu/kg): 4.6 for lentil, 2.6 for chickpea, 1.5 for wheat, and 2.8 for faba bean; corresponding values for dried shoots (mg Cu/kg) were 6.3 for lentil, 3.3 for chickpea, 2.8 for wheat, and 3.0 for faba bean.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号