Effects of harvest time and storage on dietary fibre components in various cultivars of white cabbage (Brassica oleracea var capitata)

The effect of harvest time and storage on dietary fibre content and composition was investigated in six cultivars of white cabbage (Brassica oleracea var capitata). Three cultivars were of early maturity type (SW Nordpol, Rolly and Balbro) and three of late maturity type (Predikant, Hanna and Lion). The average total dietary fibre (TDF) content was 241 g kg^?1 dry matter (DM) (CV = 13), of which approximately 25% was soluble (CV = 15). The main dietary fibre components were glucose (37%), uronic acid (32%), arabinose (12%) and galactose (8%) residues. Early cultivars generally had a lower TDF content than late maturity types, due to a lower amount of both insoluble (arabinose, galactose and glucose) and soluble (arabinose) polymers. An early cultivar, Rolly, had the highest solubility, 33%, versus 25 ± 4% for the other cultivars. The early cultivar SW Nordpol had a similar TDF content and proportion of soluble dietary fibre (SDF) to the late cultivar Hanna, but the dietary fibre composition was different, with the early cultivar having a lower proportion of arabinose residues. Storage for 6 weeks had minor effects on the dietary fibre. After further storage of the late maturity cultivars, there was an increase in insoluble dietary fibre (IDF) (glucose and uronic acid residues) and a decrease in SDF (arabinose and galactose residues). As a consequence the solubility of TDF decreased from 29 to 19% on average. Harvesting before physiological maturity was reached resulted in a somewhat lower content of TDF and IDF for two cultivars (Predikant and Hanna), while SDF was more or less unaffected for all cultivars. Long‐term storage had fewer effects on cabbage harvested prior to maturity than when harvested at the right physiological maturity. It is concluded that the observed differences between cultivars and after long term storage are of such magnitude that they may affect nutritional properties of the dietary fibre. © 2002 Society of Chemical Industry     

Antioxidant activity and dietary fibre of Prensal Blanc white grape (Vitis vinifera) by‐products

Stem and pomace of a white grape (Vitis vinifera) variety, Prensal Blanc, were studied for the first time: general composition and dietary fibre components together with the total soluble polyphenol content and antioxidant activity. Both by‐products present high contents of total dietary fibre (TDF), 790 g kg^?1 d.m. (stem) and 716 g kg^?1 d.m. (pomace). Values of the soluble dietary fibres in relation to TDF differed: 5% (stem) and 14.4% (pomace). Similar values of Klason lignin were found: 229 g kg^?1 (stem) and 278 g kg^?1 (pomace), however, the pomace exhibited more than twice the content of the condensed tannins (168 g kg^?1) with regard to the stem (79 g kg^?1). Notable were the high resistant protein contents of both by‐products. Stem and pomace showed appreciable amounts of total soluble polyphenols (87 g kg^?1 against 35 g kg^?1 respectively). The free radical scavenging capacity of the former by‐products was determined using the 2,2‐diphenyl‐1‐picrylhydrazyl radical (DPPH) method, obtaining EC₅₀ values of 0.79 g d.m. g^?1 DPPH (stem) and 1.32 g d.m. g^?1 DPPH (pomace). These data shows that both vinification by‐products from the Prensal Blanc variety are a good source of dietary fibre and have antioxidant properties.     

脱蛋白结合超微粉碎对豆渣膳食纤维成分及功能特性影响

研究脱蛋白方法结合超微粉碎处理豆渣对其化学组成和功能特性的影响,当豆渣样品进行酶或碱处理时,它的总膳食纤维(TDF),不溶性膳食纤维(IDF)的质量分数分别增加了18.6-32.9%,22.6-34.4%,并且它们的功能特性(持水力,膨胀力和持油力)显著(p < 0.05)增加,但可溶性膳食纤维(SDF)质量分数与处理前豆渣没有显着差异。经超微粉随后,随着豆渣膳食纤维粒径减小,豆渣膳食纤维中可溶性膳食纤维质量分数提高了170% 以上,持水力和膨胀力显着下降(p < 0.05),持油力先下降后上升。结果表明,应用碱性蛋白酶和超微粉碎进行前处理,得到的豆渣中TDF和SDF的含量最高,这可能是在食品中加工高质量膳食纤维的潜在方法。     

滇橄榄果渣膳食纤维的提取及其体外吸附性能研究

本文以滇橄榄果渣为原料,优化其膳食纤维的碱法提取工艺,同时探讨了滇橄榄果渣、总膳食纤维（total dietary fiber,TDF）、水不溶性膳食纤维（insoluble dietary fiber,IDF）及水溶性膳食纤维（soluble dietary fiber,SDF）的理化性质及其体外吸附能力。结果表明:碱法提取滇橄榄果渣膳食纤维的最优工艺为:NaOH浓度为8 g/L,料液比为1:35（g:mL）,70 ℃处理40 min,IDF和SDF的得率分别为61.72%±0.04%、17.57%±0.03%。滇橄榄果渣及其膳食纤维均具有较好的水化特性和持油力,TDF的持水力最低但膨胀力最高,与滇橄榄果渣、SDF和IDF存在显著性差异（P<0.05）;SDF的持油力、膨胀力和对脂肪的吸附能力均较低,但在模拟胃环境（pH2）的条件下对胆固醇和NO₂?的吸附能力均高于滇橄榄果渣、TDF和IDF,且存在显著性差异（P<0.05）。滇橄榄果渣及其膳食纤维对胆固醇和NO₂?的吸附与pH有关,TDF和SDF在模拟胃环境的条件下对胆固醇的吸附能力强于模拟小肠环境,滇橄榄果渣和IDF则相反;四个样品在模拟胃环境的条件下对NO₂?的吸附能力均强于模拟小肠环境。本文对滇橄榄果渣膳食纤维的提取及性能研究,可为其在保健食品中的应用提供一定的理论参考。     

火龙果皮中膳食纤维含量及其物理化学特性

以火龙果果皮为原料,制备3种不同粒径的火龙果高膳食纤维果皮粉(DFRPP)：DFRPP80、DFRPP140和DFRPP250,测定其总膳食纤维、可溶性和不溶性膳食纤维含量,并对其持水性、持油性、溶胀性和对葡萄糖的透析阻滞能力进行研究。结果表明：粒径为58～104μm的DFRPP140中总膳食纤维和可溶性膳食纤维含量最高,分别为79.37%和33.07%,其可溶性膳食纤维与不溶性膳食纤维具有良好的比例模式,且其持水性、持油性和溶胀性最强,分别为54.20g/g、2.65g/g和50.63mL/g;其对葡萄糖的透析阻滞系数最好,在20、40、60min时分别是60.24%、59.24%和62.83%。DFRPP140可作为食品膳食纤维的优良来源。     

Diferulates as structural components in soluble and insoluble cereal dietary fibre

Cell wall cross‐linking can have a substantial effect on the properties of the wall. To estimate cross‐linking (between arabinoxylans) in cereal fibres, dehydrodiferulate levels were measured in soluble and insoluble dietary fibre (SDF and IDF) isolated from whole grains of maize (Zea mays L), wheat (Triticum aestivum L), spelt (Triticum spelta L), rice (Oryza sativa L), wild rice (Zizania aquatica L), barley (Hordeum vulgare L), rye (Secale cereale L), oat (Avena sativa L) and millet (Panicum miliaceum L). After saponification of the cereal fibres the extracts were investigated for dehydrodimers of ferulic acid using GLC–MS and GLC–FID. From most cereal IDF the whole spectrum of dehydrodiferulic acids (DFAs) (8‐5′‐, 8‐8′‐, 5‐5′‐, 8‐O‐4′‐ and 4‐O‐5′‐coupled) could be identified. The absolute contents of total DFAs ranged between 2.4 and 12.6 mg g^?1. With the exception of 4‐O‐5′‐coupled DFA, the whole range of DFAs was also detected from cereal SDF but only in amounts of 40–230 µg g^?1. It was estimated that arabinoxylans of cereal IDF contain 8–39 times more diferulates than arabinoxylans of cereal SDF (where measurement of DFA levels in SDF was possible). In cereal IDF, 8‐5′‐coupled dimers dominated, whereas in cereal SDF, 8‐8′‐coupled dimers were relatively enhanced and often became the major dimers. © 2001 Society of Chemical Industry     

油茶粕膳食纤维的超声辅助酶法提取工艺优化及理化性质分析

膳食纤维（Dietary Fiber，DF）具有很多生理功能及突出的应用前景，而可溶性膳食纤维（Soluble Dietary Fiber，SDF）的生理特性要优于不溶性膳食纤维（Insoluble Dietary Fiber，IDF）。为提高油茶粕DF中SDF的得率，以SDF得率作为评价指标，采用超声辅助酶法，通过单因素实验对酶添加量、超声时间、超声功率、料液比四个因素进行研究，并在单因素实验的基础上进行响应面优化试验，并对得到的DF进行理化性质及结构分析。结果表明，最佳提取工艺为酶添加量0.2%、超声时间31 min、超声功率210 W、料液比1:23 g/mL，SDF得率为12.43%，此时IDF得率为68.39 %。油茶粕总膳食纤维（Total Dietary Fibre，TDF）的持水力为4.36 g/g、持油力为3.67 g/g、膨胀力为6.83 mL/g，胆固醇吸附率在pH2时为5.79 mg/g，pH7时为8.38 mg/g，葡萄糖吸附率为11.49 mg/g。通过结构表征的分析推测油茶粕TDF中含有木质素、纤维素、半纤维素及糖类物质，TDF表面疏松多孔、凹凸不平，粒径为50.699 nm。本研究提高了SDF得率，证明油茶粕TDF具有较好的理化性质及结构，为提高油茶粕的附加价值提供了参考。     

Effect of variety and processing on nutrients and certain anti-nutrients in field peas (Pisum sativum)

The effect of variety and processing (soaking, cooking and dehulling) on nutrients and anti-nutrients in field peas (Pisum sativum) was investigated. Analysis of variance showed that variety had a significant effect on crude protein, starch, ash, soluble dietary fibre (SDF), insoluble dietary fibre (IDF), total dietary fibre (TDF), trypsin inhibitor activity (TIA), minerals, phytic acid, sucrose and oligosaccharides. Soaking and cooking increased protein content, IDF, TDF, Ca, Cu, Mn and P in peas whereas ash content, Fe, K, Mg, Zn, sucrose and oligosaccharides were reduced. TIA was increased by soaking but reduced by cooking. Cooking was more effective than soaking in reducing oligosaccharides. Dehulling increased crude protein, starch, K, P, phytic acid, stachyose and verbascose content but reduced SDF, IDF, TDF, Ca, Cu, Fe, Mg and Mn.     

七种药食两用中药膳食纤维体外抗氧化及胆酸盐结合能力研究

为了探究药食两用中药膳食纤维的生理活性,选择党参、黄芪、山药、甘草、灵芝、人参、西洋参七种药食两用中药制备了水溶性膳食纤维（soluble dietary fiber,SDF）、非水溶性膳食纤维（insoluble dietary fiber,IDF）和总膳食纤维（total dietary fiber,TDF）,并对其体外抗氧化活性和胆酸盐结合能力进行了研究。结果表明:七种膳食纤维成分的理化性质和体外活性存在显著差异。党参、灵芝和人参TDF分别具有最高的持水性（11.26 g/g）,持油性（6.36 g/g）和溶胀性（9.12 mL/g）。黄芪SDF、山药SDF和西洋参TDF分别具有最高的DPPH自由基清除率（96.27%）,羟自由基清除率（97.20%）和超氧阴离子自由基清除率（60.32%）,人参TDF的总抗氧化能力最强（2283.39 μmol/L/FeSO₄）。人参TDF对甘氨胆酸钠结合率最高（59.87%）,黄芪TDF对牛磺胆酸钠结合率最高（51.52%）,七种药食两用中药膳食纤维对甘氨胆酸钠的平均结合率（34.12%~53.73%）高于对牛磺胆酸钠的平均结合率（28.16%~45.47%）。本研究证实了党参等七种药食两用中药膳食纤维具有良好的理化性质和生理活性,具有功能性食品的开发潜力。     

成熟度对甘蓝膳食纤维单糖组成及抗氧化活性的影响

研究成熟度(成熟度A~D分别为最早成熟期采摘样品及每隔5 d采摘的样品)对甘蓝膳食纤维含量、单糖组成及抗氧化活性的影响。结果表明,随着甘蓝的成熟,可溶性膳食纤维(soluble dietary fiber,SDF)含量逐渐降低,非水溶性膳食纤维(insoluble dietary fiber,IDF)和总膳食纤维(total dietary fiber,TDF)含量则先增加后降低。不同成熟度甘蓝膳食纤维单糖组成均为葡萄糖醛酸、半乳糖醛酸、葡萄糖、半乳糖、鼠李糖、阿拉伯糖,但各单糖的相对含量对成熟度差异显著。随着成熟度增加,组成甘蓝SDF的单糖中,葡萄糖醛酸含量持续降低;葡萄糖与半乳糖含量显著增加;半乳糖醛酸、鼠李糖和阿拉伯糖含量变化呈抛物线,且在成熟度B时达到最高。随着甘蓝的成熟,甘蓝IDF的葡萄糖醛酸和半乳糖醛酸含量显著增加;葡萄糖和半乳糖含量在前期无变化,从成熟度D开始显著降低;阿拉伯糖含量变化呈抛物线,并在成熟度D达到最高;而鼠李糖含量始终保持恒定。随着甘蓝的成熟,其SDF与IDF的1,1-二苯基-2-三硝基苯肼自由基清除能力和三价铁还原抗氧化能力增强,而2,2’-联氮-二(3-乙基苯并噻唑啉-6-磺酸)自由基清除能力在成熟度C达到最强。     

Broad bean and pea by‐products as sources of fibre‐rich ingredients: potential antioxidant activity measured in vitro

BACKGROUND By‐products generated during the processing of plant food can be considered a promising source of dietary fibre as a functional compound. The dietary fibre composition, soluble sugars and antioxidant activity of the extractable polyphenols of pea and broad bean by‐products have been analysed in this study. RESULTS: Total dietary fibre using AOAC methods plus hydrolysis (broad bean pod: 337.3 g kg^?1; pea pod: 472.6 g kg^?1) is higher (P < 0.05) in both by‐products than with the Englyst method (broad bean pod: 309.7 g kg^?1; pea pod: 434.6 g kg^?1). The main monomers are uronic acids, glucose, arabinose and galactose in broad bean pods. However, pea pods are very rich in glucose and xylose. The soluble sugars analysed by high‐performance liquid chromatography in both by‐products have glucose as the most important component, followed by sucrose and fructose. The ferric reducing antioxidant power (broad bean pod: 406.4 µmol Trolox equivalents g^?1; pea pod: 25.9 µmol Trolox equivalents g^?1) and scavenging effect on 2,2‐diphenyl‐1‐picrylhydrazyl radical (EC₅₀ of broad bean pod: 0.4 mg mL^?1; EC₅₀ of pea pod: 16.0 mg mL^?1) were also measured. CONCLUSIONS: Broad bean and pea by‐products are very rich in dietary fibre, particularly insoluble dietary fibre and their extractable polyphenols demonstrate antioxidant activity. Therefore they might be regarded as functional ingredients. Copyright © 2011 Society of Chemical Industry     

Enhancement of short chain fatty acid formation by pure cultures of probiotics on rice fibre

The formation of SCFA and the digestion of rice fibre using the following probiotics (Lactobacillus rhamnosus, Lactobacillus acidophilus, Bifidobacterium longum, Bifidobacterium breve) was compared using total dietary fibre (TDF), insoluble dietary fibre (IDF) and soluble dietary fibre (SDF) from two varieties (milling grades) of rice. The milling grade of the rice had no significant effect (P < 0.05) on the SCFA formation and the digestion after 6, 24 and 48 h fermentation. SCFA formation from the fermentation of the fibre fractions of both rice varieties, followed the pattern of TDF > SDF > IDF for all the probiotics tested and major difference between the species was the time to form the SCFA. The pattern of SCFA formation from both rice fibre fractions was acetate > propionate > butyrate for all the organisms with no significant difference between the micro‐organisms (P < 0.05) although the ratio of acetate:propionate:butyrate was lower for Bifidobacterium spp. Lactobacillus spp. digested 60–80% of fibre whereas Bifidobaceria digested 75–85% of the rice fibre fractions from both rice samples. There was no significant difference in the ability of the micro‐organisms tested to utilise the different varieties of rice (P > 0.05).     

Influence of germination on the soluble carbohydrates and dietary fibre fractions in non-conventional legumes

Influence of light exposure during germination on structural and soluble carbohydrates including total dietary fibre (TDF), insoluble dietary fibre (IDF) and soluble (SDF) dietary fibre fractions and also raffinose family oligosaccharides (RFOs) was studied in non-conventional legumes Vigna unguiculata (cowpea), Canavalia ensiformis (jack bean), Stizolobium niveum (mucuna), and Lablab purpureus (dolichos), and compared to a well known and used Glycine max (soybean). Non-conventional legumes were rich in DF, mainly IDF, which represented 93–97% of TDF. It was relevant the proportion of protein that remained associated to the insoluble DF matrix. Non-conventional legumes exhibited important levels of RFOs but their profile was different depending on the tropical seed. The germination of seeds produced changes in the carbohydrate fraction, mainly an increase of TDF in most instances, except for soybean, and a drastic reduction of RFOs, from 98% to 63%, with the corresponding increase in the amounts of total soluble sugars.     

A new nanofibrillated and hydrophobic grafted dietary fibre derived from bamboo leaves: enhanced physicochemical properties and real adsorption capacity of oil

Dietary fibre (DF) has been used for enhancing health benefits for centuries. In this study, an innovative nanofibrillated cellulose (NFC) was obtained by the combined application of high‐density steam flash‐explosion and enzymatic hydrolysis of bamboo leaves. The NFC prepared in this study was characterised by long, well‐defined and distinct NFC fibres, exhibiting excellent functional properties (water retention capacity: 20 g water g^?1, swelling capacity: 97 mL g^?1, oil‐holding capacity: 13 g oil g^?1, and higher adsorption of bile acids and cholesterol). Octenyl succinic anhydride (OSA) was further successfully grafted onto the NFC to improve its hydrophobicity. Thus, the oil‐holding capacity of the NFC reached 18.5 g oil g^?1 and the adsorption of bile acids and cholesterol increased twofold. A gastrointestinal digestion experiment further showed that the nanofibrillated and hydrophobic grafted dietary fibre represented a high‐quality dietary supplement providing enhanced health benefits, highlighted by the strong ability to absorb oil. These results indicate that the OSA‐NFC has a great potential for use as a functional ingredient in food products.     

Physicochemical Properties of Dietary Fibres Prepared from Ambarella (Spondias cytherea) and Mango (Mangifera indica) Peels

The preparation of fibres from mango and ambarella peels can offer a way to upgrade by-products. Comparatively to lime, ambarella and mango fibres were prepared from their corresponding peels using ethanolic treatment (85% at 70 °C/5 min). The peels were characterised for their dry matter content, pH and apparent viscosity. The soluble dietary fibre (SDF) and insoluble dietary fibre (IDF) contents of the samples were determined. Hydration capacity of these fibres was evaluated. Results showed that the ethanolic treatment of the peels (85% at 70 °C/5 min) had significant (p?<?0.05) effects on the contents of neutral sugars and uronic acid (from 105 to even 203 mg/g in case of mango fibre). For ambarella fibres, the proportion of IDF (51%) was highest and that of SDF (34%) was lowest. Mango and lime fibres exhibited similar values of IDF (40–43%) and SDF (50–57%). Mango peel fibres had higher hydration capacities than ambarella and lime fibres. The best dietary fibres content and the high hydration capacities of mango peel fibres favour their exploitation in dietary fibre-rich foods preparation.     

Dietary fiber profile of barley flour as affected by extrusion cooking

Barley grains, Phoenix and CDC-Candle, were extruded in a twin-screw extruder at 90−140 °C and 20–50% moisture level. Effects of extrusion conditions on total (TDF), soluble (SDF), and insoluble dietary fiber (IDF) were determined. The content of SDF and TDF increased upon extrusion cooking of both types of barley flours. The changes in IDF content were found to be variety-dependent. Only a minor decrease in IDF content of CDC-Candle barley was found, but an increase in IDF content of Phoenix was observed at all extrusion temperatures. The increase in SDF, in both barleys, could be due to the transformation of some IDF into SDF during extrusion and the formation of additional SDF by transglycosidation. The increase in IDF in Phoenix flour could be due to the formation of retrograded amylose [resistant starch (RS3)] during extrusion cooking and subsequent cooling.     

Effect of grape dietary fibre on the storage stability of innovative functional seafood products made from farmed meagre (Argyrosomus regius)

Two groups of farmed meagre (Argyrosomus regius) sausages were studied regarding quality changes and antioxidant capacity during a 98‐day storage experiment at 2 ± 2 °C. Control sausages contained 3.9% (w/w) of inner pea dietary fibre (IPDF) and the other group contained 0.9% (w/w) IPDF plus 3.0% (w/w) of antioxidant grape dietary fibre (AGDF). The control and AGDF meagre sausages presented a high nutritional value, given their low caloric content, fatty acid profile, amino acid composition and high DF content. Both products were remarkably stable over storage time. The AGDF had an effective antioxidant capacity, proven not only by the radical scavenging activity (90.0–91.0% vs. 82.1–85.4%) and reducing power (8.13–9.10 mg ascorbic acid equivalent g^‐1 vs. 4.16–4.24 mg ascorbic acid equivalent g^?1) measurements, but also by the lower thiobarbituric acid reactive species (TBARS) values (0.78–1.10 vs. 1.50–2.08 mg malonaldehyde kg^?1) over storage time. AGDF seemed to present antimicrobial effect, since on the 63rd day (beginning of significant microbial growth), the control sausages had more than 3 log CFU g^?1 and AGDF sausages much <3 log CFU g^?1. The sensory assessment pointed to some loss of textural quality, more accentuated in the AGDF sausages.     

琯溪蜜柚柚皮膳食纤维提取及其理化特性

以福建省平和县琯溪蜜柚为材料,以NaOH溶液浓度、提取温度和加热时间设计三因素三水平正交实验,以总膳食纤维(TDF)提取率、不溶性膳食纤维(IDF)与水溶性膳食纤维(SDF)的比值接近3∶1为目标,优化柚皮膳食纤维提取工艺。结果表明:柚皮膳食纤维(DF)最佳提取工艺为碱液浓度8%,提取温度75℃,加热时间90 min,其提取率为75.12%,IDF/SDF比值为2.12。柚皮TDF粒径主要分布在<120目的范围,占总比重的30.13%,其次是位于120～140目的DF膳食纤维,占总比重的21.84%;SDF具有良好的膨胀力,达到17.642 0 g/g,IDF持水力较好,为5.711 5 g/g;柚皮DF对亚硝酸盐(NO2-)吸附能力强,且DF对NO2-的吸附量随着时间的延长而增加,至240 min时吸附量最高,达到18.01 g/g(pH 2)和15.92 g/g(pH 7),相同时间内,在pH 2的模拟环境下,DF对NO2-吸附能力优于pH 7的;柚皮DF对脂肪酸的吸附效果良好,且相同时间内DF对不饱和脂肪酸的吸附量(1.026 0 g/g)高于对饱和脂肪酸的(1.124 0 g/g),说明DF吸附动物性油脂效果更好。     

The influence of rice fibre fractions on the in vitro fermentation production of short chain fatty acids using human faecal micro flora

A study was conducted to assess the effects of rice dietary fibre on the fermentative activity of human faecal microflora. Dietary fibre was extracted from four commercially available Sri Lankan rice varieties [LD 356, AT 353 (red in colour); BG 352, and BG 358 (white in colour)], and separated into individual fractions of total dietary fibre (TDF), insoluble dietary fibre (IDF) and soluble dietary fibre (SDF). Four healthy human subjects were given a diet containing the four rice varieties for more than 4 months prior to the study. Faecal microflora was obtained from human volunteers, after the 4 months of rice based diet, and used for anaerobic fermentation of the individual rice fibres. Short Chain Fatty Acid (SCFA) production was analysed at 0, 2, 4, 6 and 24 h by gas liquid chromatography. Among the SCFA, acetate was the most abundant acid formed in all rice varieties. The fibre fractions from rice variety LD 356 (TDF16.73%, SDF 3.57%, 11.9% IDF) gave the highest yield of SCFA while the variety BG 358 gave the least. Total dietary fibre of all rice varieties contributed to produce more SCFA than the individual soluble dietary fibre and insoluble dietary fibre fractions.