“Dietary fibre”: moving beyond the “soluble/insoluble” classification for monogastric nutrition, with an emphasis on humans and pigs

This review describes dietary fibres originating from a range of foods,particularly in relation to their plant cell walls.It explores the categorization of dietary fibres into "soluble" or "insoluble".It also emphasizes dietary fibre fermentability,in terms of describing how the gastro-intestinal tract(GIT) microbiota respond to a selection of fibres from these categories.Food is categorized into cereals,legumes,fruits and vegetables.Mention is also made of example whole foods and why differences in physico-chemical characteristics between "purified" and "non-purified"food components are important in terms of health.Lastly,recommendations are made as to how dietary fibre could be classified differently,in relation to its functionality in terms of fermentability,rather than only its solubility.

Dietary fibre enrichment of supplemental feed modulates the development of the intestinal tract in suckling piglets

Background:Commercial pre-weaning diets are formulated to be highly digestible and nutrient-dense and contain low levels of dietary fibre.In contrast,pigs in a natural setting are manipulating fibre-rich plant material from a young age.Moreover,dietary fibre affects gastrointestinal tract(GIT)development and health in older pigs.We hypothesised that supplemental diets that contain vegetal fibres are accelerating GIT development in suckling piglets in terms of size and functionality.From d 2 of life,sow-suckled piglets had access to a low fibre diet(CON),a diet with a fermentable long-chain arabinoxylan(lc-AXOS),a diet with a largely non-fermentable purified cellulose(CELL),or a diet containing both fibres.During the initial 2 weeks,the control diet was a high-density milk replacer,followed by a dry and highly digestible creep meal.Upon weaning at 25 d,15 piglets from each treatment group,identified as eaters and originating from six or seven litters,were sacrificed for post-mortem examination of GIT morphology,small intestinal permeability and metabolic profile of the digesta.The microbiota composition of the mid-colon was evaluated in a sub-set of ten piglets.Results:No major statistical interactions between the fibre sources were observed.Piglets consumed the fibrecontaining milk supplements and creep diets well.Stomach size and small intestinal permeability was not affected.Large intestinal fill was increased with lc-AXOS only,while relative large intestinal weight was increased with both fibre sources(P<0.050).Also,CELL decreased ileal pH and tended to increase ileal DM content compared to CON(P<0.050).Moreover,the concentration of volatile fatty acids was increased in the caecum(P<0.100)and midcolon(P<0.050)by addition of CELL.lc-AXOS only stimulated caecal propionate(P<0.050).The microbiota composition showed a high individual variation and limited dietary impact.Nonetheless,CELL induced minor shifts in specific genera,with notable reductions of Escherichia-Shigella.Conclusions:Adding dietary fibres to the supplemental diet of suckling piglets altered large intestinal morphology but not small intestinal permeability.Moreover,dietary fibre showed effects on fermentation and modest changes of microbial populations in the hindgut,with more prominent effects from the low-fermentable cellulose.

Optimization of Protein Content and Dietary Fibre in a Composite Flour Blend Containing Rice (<i>Oryza sativa</i>), Sorghum [<i>Sorghum bicolor</i>(L.) Moench] and Bamboo (<i>Yushania alpine</i>) Shoots

Initiatives on tackling food insecurity among global emerging economies are being focused on enriching native staple foods with locally available nutritious underutilized crops. The objective of this study was to optimize protein content and dietary fibre in rice (Oryza sativa) flour using Sorghum (Sorghum bicolor L.) and Bamboo shoots (Yushania alpine). An extreme vertices design of mixture approach with 11 runs was employed in the study using MINITAB® software. The 11 blends from 11 generated runs and individual ingredient samples were analyzed for nutritional composition. Energy value and energy-to-protein ratio for the samples was calculated. Bamboo shoots flour (BSF) had the highest content for all proximate components except total carbohydrates on dry weight basis. Rice had the highest content of total carbohydrates at 77.71% and energy to protein ratio of 53.72 kcal/g. Sorghum had the highest mean total phenolic and condensed tannins of 45.512 (mg GAE/kg) and 2.512 (mg CE/g) while rice the least with 0.042 (mg GAE/kg) and 0.102 (mg CE/g), respectively. Fresh bamboo shoots had the highest level content of HCN of 117.81 mg/kg. Other dried ingredients had a mean HCN content of 2.313, 1.584 and 0.066 mg/kg for dried BSF, sorghum and rice respectively. Increasing the quantity of BSF and sorghum flour in the blends consequentially increased the protein content, dietary fibre and total minerals. Optimum blend was established to be 50:27:23 for rice, sorghum and BSF, respectively. This blend had 13.4% protein, 6.2% dietary fibre and 3.9% total minerals. Regression analysis showed that apart from dry matter, all other constituents were significantly predictable during optimization with R2 > 0.7530. Cluster analysis showed that the nutritional components analyzed are in four main clusters. Cluster 1: Dry matter and protein digestibility, cluster 2: Carbohydrates, energy value and energy ratio, cluster 3: Protein, fibre and ash while cluster 4: Crude fat only. These findings of the optimum composite ratio and other blends could contribute in addressing the food insecurity for low income countries.

不同提取方式对山楂果渣可溶性膳食纤维结构及功能特性的影响

山楂提取多酚后剩余果渣中含有丰富的膳食纤维。为了有效利用山楂资源,该文采用微波辅助酶解法(microwave-enzymatic extraction of soluble dietary fiber,MSDF),酶解法(enzymatic extraction of soluble dietary fiber,ESDF),碱法(alkaline extraction of soluble dietary fiber,NSDF)提取山楂果渣可溶性膳食纤维(water-soluble dietary fiber,SDF),并比较3种提取方式对SDF的理化、结构和功能特性的影响。结果表明,MSDF与ESDF单糖成分以半乳糖醛酸和阿拉伯糖为主,NSDF葡萄糖含量最高,其次是半乳糖醛酸。采用傅里叶红外光谱、X-射线衍射和扫描电镜分析发现,3种方法获得的SDF结构都符合天然纤维素Ⅰ型结晶结构,糖类特征官能团。MSDF质地疏松,呈雪花状,更有利于膳食纤维的保水性、吸附性。MSDF的DPPH自由基清除率半抑制浓度为0.07 mg/mL,持水力和持油力分别为2.69 g/g和0.51 g/g,优于ESDF和NSDF。体外降糖降脂实验表明,3种方法提取的山楂SDF都具有较好的α-淀粉酶的抑制能力,胆固醇吸收能力和牛磺胆酸钠结合能力等,其中MSDF降血糖、降血脂效果优于其他2种方法制备的SDF。因此,微波辅助酶法与酶法和碱法相比,具有SDF提取率高,DPPH抗氧化性高,功能特性好等优点。该研究结果可为阐明山楂果渣膳食纤维理化特征及功能特性提供数据支撑,对山楂高附加值产品开发具有重要意义。

竹笋膳食纤维生物活性研究现状与展望

竹笋及其加工剩余物中含有丰富的膳食纤维,虽然其具有良好的食品开发价值,但利用率较低,资源浪费严重。竹笋膳食纤维在降糖、降脂和抗氧化等方面具有良好的生物活性,是功能食品的潜在原料。充分利用竹笋膳食纤维有利于提高竹笋附加值。文章梳理、总结了竹笋膳食纤维制备方法和生物活性等方面的研究成果,提出了今后的研究重点,旨在为深入研究竹笋膳食纤维制备技术、功能活性作用机制及其应用提供参考。

刺梨果渣及其膳食纤维提取物对面条品质的影响

刺梨果渣虽然富含多种功能性成分,但整体利用度不高。为提高刺梨果渣的利用率,该研究将不同粒径刺梨果渣及其膳食纤维提取物添加到面条中,研究不同粒径果渣或其膳食纤维提取物对面条品质特性和生物活性的影响。结果表明,添加60~80μm果渣或1~10μm果渣膳食纤维提取物均能显著改善面条的煮制特性,其吸水性较空白分别提高了9.26%、5.91%(P<0.05)。煮制后,添加250μm果渣面条的硬度、弹性最大。添加1~10μm果渣或0.1~1μm果渣膳食纤维提取物分别使面条抗氧化的能力提升6倍和5倍。添加0.1~1μm果渣或其膳食纤维提取物使面条淀粉水解率分别降低16.14%和11.36%(P<0.05)。综上,添加1~10μm果渣膳食纤维提取物的面条,吸水率、硬度、弹性、咀嚼性、膳食纤维含量、抗氧化活性显著提高,损失率、亮度值、淀粉水解率显著降低。刺梨果渣及膳食纤维提取物可作为功能性面制品研发的良好资源,为刺梨果渣的精深加工提供研究基础。

山竹壳膳食纤维结合酚提取工艺的优化及抗氧化活性分析

目的对比酸法、碱法和酶法水解对山竹壳膳食纤维结合酚(bound polyphenols in mangosteen peel,MDF-PP)的提取效果,并考查其抗氧化性。方法首先依次采用α-高温淀粉酶、木瓜蛋白酶和糖化酶对山竹壳进行酶解,得到膳食纤维(mangosteen peel dietary fibre,MDF)。随后分别采用酸法水解、碱法水解和酶法进行MDF-PP提取,并分别测定了所得MDF-PP的1,1-二苯基-2-三硝基苯肼自由基清除率,对MDF-PP得率最高、抗氧化性最强的提取方法进行工艺优化。结果碱法水解提取MDF-PP效果最好,其所得MDF-PP抗氧化活性最强。最佳碱法水解提取工艺条件为NaOH浓度为24 moL/L、碱水解时间为4 h、液固比为30:1 mL/g。在该条件下MDF-PP得率为(88.44±1.10)mg GAE/10 g DW,与预测结果接近。结论建立的响应面模型良好,可用于预测碱法提取山竹壳时MDF-PP得率,MDF-PP具有较好的抗氧化性。

Identification and characterization of soybean dreg soluble dietary fibre by combination of extrusion pre-treatment and enzymatic modification

OBJECTIVES:Soybean dreg is a by-product of soy milk processing,which contains high levels of soluble dietary fibre(SDF).In this study,we aimed to provide comprehensive processes of pre-treated extrusion for the improving structure and properties of soybean dreg soluble dietary fibre(SDSDF),which would be a valuable approach to enhance physiological activity.METHODS:Here,we characteristic the functional role of SDSDF employing to extrusion pretreatment.Soybean dregs were pre-treated using the twin screw extrusion method followed by enzymatic modification using neutral protease,α-amylase,glucoamylase,and cellulose to produce SDSDF.The physical properties and antioxidant activity of SDSDF were investigated.RESULTS:The morphology and crystal structure of SDSDF were observed that,through extrusion processing and enzymatic modification,the SDSDF yield increased by 106.28%.Moreover,the surface structure showed block-shaped or reticular formations in the extruded SDSDF,and the size of block-shaped cells was about 10μm.Infrared spectroscopic analysis showed that a characteristic absorption peak of polysaccharide appeared at 1631 cm−1 during extrusion processing.However,after extrusion processing,decreased absorption peaks were observed for the extruded SDSDF.Furthermore,XRD analysis showed that the 2θdiffraction peak changed at 24.16°for the extruded SDSDF.CONCLUSIONS:The overall findings suggest that the water holding capacity(WHC),oil holding capacity(OHC),expansibility,and the water solubility were significantly decreased in extruded SDSDF.In addition,the scavenging ability of 1,1-diphenyl-2-picrylhydrazyl(DPPH),-OH,O_(2)^(-),and the total reducing power were significantly improved,indicating that beneficial changes had taken place in the crystal structure of cellulose or hemicellulose to improve the physiological activity in extruded SDSDF.

Dietary fibre basics: Health, nutrition, analysis, and applications

Over the past decades,dietary fibre(DF)has been well studied with abundant evidence on its health benefits.Advances in nutritional studies always lead the way followed by the food applications.Food scientists and technologists then explored the applications of DF in a variety of food products through examination and utilization of fibres from various conventional and uncommon sources including agro-food processing by-products.However,the current intake levels of fibre and fibrerich foods are still far below recommended values in most nations worldwide.In addition,research is needed to substantiate different mechanistic effects of intrinsic,intact fibres presented originally in the food matrix and the isolated,refined fibre added back to the novel food products.Standardized quantification methods for DF are needed for various reasons including broad range of sources,complicated chemical structures,and ever-changing definitions from various regulatory bodies.On the other hand,there are more consumer demands for clean labels or precise information on daily values(DV%),alongside more restricted regulations for certain nutritional claims such as‘high fibre’.It is clear that all these demands create a practical pressure on professionals working in the food industry,particularly at quality assurance(QA)positions,on how to obtain reliable data from DF analysis to meet regulatory and labelling requirements.Fortunately,with the most recent Codex definition and advanced instruments that are capable to automate the analytical procedures and produce consistent results,it is foreseeable that global harmonization on DF studies can be achieved.Meanwhile,advanced processing technologies such as dry fractionation,enzymatic conversion,and micronization present promising opportunities for R&D professionals to advance the DF utilization and applications in functional food development.

How does the addition of mushrooms and their dietary fibre affect starchy foods

Mushrooms contain multiple bioactive compounds of which dietary fibre is a representative type.Fortification of extracted or naturally derived dietary fibre in staple starchy foods constitutes a strategy to increase fibre intake in terms of cardiovascular disease and other metabolic diseases.Food matrix is viewed as a physical domain containing nutrients in which interactions and behaviours are different from those in isolation or free state.The nutritional effect of mushrooms'addition in the starchy food matrix is reviewed together with the alterations of cooking properties.Prospective studies include nutrients bioaccessibility due to the interfere of dietary fibres in consideration of their types and quality.The future approach to shaping microbial colonisation in the digestive tract through metabolites such as short-chain fatty acids from dietary fibres is required to sustain host physiology and health.

一种水溶性膳食纤维曲奇饼干的研制

为改善传统曲奇饼干高糖高热量的问题,以低筋面粉为主要原料,探讨黄油、蔗糖、低聚果糖和木糖醇的用量对饼干感官品质的影响。通过单因素试验和正交试验确定水溶性膳食纤维曲奇饼干的最佳配方为以100 g低筋面粉为基准,黄油用量60 g,蔗糖用量10 g,木糖醇用量5 g,低聚果糖用量12.5 g。以此配方制作的水溶性膳食纤维曲奇饼干口感酥脆、香味浓郁、甜度适中且热量较低,是一款具有消费潜力的饼干。

从罗汉果渣中提取水不溶性膳食纤维的研究

采用化学法、酶法、酶与化学结合法从罗汉果渣中提取水不溶性膳食纤维,并且对三种提取方法所得的水不溶性膳食纤维产品特性进行了分析比较。研究结果表明,采用酶与化学结合法提取到的水不溶性膳食纤维产品纯度最高、生理活性最好,产率为87.15％,蛋白质含量为2.03％,持水力与膨胀力分别为3.807 g·g-1和1.69 mL·g-1。但从成本和实用方面考虑,还是以化学法为宜。

膳食纤维营养保健香肠的研制

将不同种膳食纤维大豆纤维、苹果纤维和魔芋精粉添加到香肠制品中,制成膳食纤维营养保健香肠。通过对比实验,研究膳食纤维对产品性能和质量的影响;利用正交试验及模糊数学评判确定膳食纤维香肠的主要原料最佳配比为:马铃薯淀粉15%、苹果纤维8%、大豆蛋白4%、猪肉皮6%。经产品质量检验,其各项指标均符合肉与肉制品国家标准。

利用牛蒡渣提取高活性膳食纤维的工艺

以牛蒡渣为原料 ,提取水溶性膳食纤维和水不溶性膳食纤维。正交试验结果表明 ,提取水溶性膳食纤维的适宜条件为 :温度 80℃ ,pH 2 0 ,时间 90min ,V (原料 ) :V (水 ) =1∶10 ,得率为1 0 % (以干渣计 ) ,成品色泽呈淡黄色 ,气味较好 ;水不溶性膳食纤维的提取条件为 :温度 60℃ ,pH2 0 ,时间 60min ,V (原料 )∶V(水 ) =1∶5 ,得率为 8 5 % (以干渣计 ) ,成品色泽呈白色 ,气味淡 ,其膨胀力高达 6 5mL/g ,持水力为 72 0 %

超微粉碎对甘薯膳食纤维成分及物化特性影响

为明晰超微粉碎对甘薯膳食纤维成分及物化特性影响,从而拓展其在食品工业中的应用,甘薯渣经筛法制备膳食纤维再进行超微粉碎处理,以大豆膳食纤维为对照,比较不同膳食纤维成分及物化特性指标。结果表明:与大豆膳食纤维相比,甘薯膳食纤维中可溶性膳食纤维、果胶、糖醛酸含量,持水性、吸水膨胀性、葡萄糖吸收能力和α-淀粉酶抑制能力显著高于大豆膳食纤维(P<0.05)。甘薯膳食纤维经超微粉碎后,可溶性膳食纤维、果胶含量上升,淀粉、纤维素含量下降,蛋白、灰分等含量无明显变化;各项物化特性指标均显著上升(P<0.05)。大豆膳食纤维、甘薯膳食纤维及超微粉碎后甘薯膳食纤维粒径分别为34.59、24.43、18.27μm,扫描电镜下,膳食纤维呈片状多孔结构。

小麦营养和健康品质研究进展

作物营养和健康品质改良正在成为世界主要作物的重要研究方向和育种目标。文中围绕铁和锌、抗性淀粉和阿拉伯木聚糖、酚酸和植物固醇,从微量营养元素、功能性膳食纤维、膳食纤维、植物生物活性物质4个方面对小麦籽粒的营养品质研究进行评述,兼顾面筋过敏和赤霉菌毒素对人体健康的影响,概括与育种工作密切相关的分析测定方法、种质资源筛选、基因定位与育种研究进展。提出国内营养和健康品质研究的重点领域,建议加强四方面的工作,(1)优先进行与人体健康密切相关的铁、锌及其生物有效性影响因子植酸含量和植酸酶活性等微量营养元素、阿拉伯木聚糖和抗性淀粉等膳食纤维、酚酸和植物固醇等植物生物活性物质含量的分析,开展大规模营养元素普查工作,筛选营养价值高的育种亲本和材料;(2)加强抗赤霉病相关研究,并将其结果尽快用于育种;(3)通过关联和连锁分析开展基因定位和克隆,发掘基因功能标记或紧密连锁的分子标记,通过与常规育种紧密结合,推动生物技术育种实用化,加快品种选育进程,提高品质育种效率;(4)通过加强国际合作与国内协作,建立小麦品质研究协作网,推广普及现有实用技术并研究新型营养品质快速检测技术。

莲藕渣中多糖的提取及性质初步研究

本实验综合利用提取淀粉后的莲藕渣提取水溶性多糖和不溶性膳食纤维,并对水溶性多糖的结构及不溶性膳食纤维的特性进行了初步研究。通过水提醇沉、Sevag法去蛋白得到粗多糖NPh,得率为2.50%。离子交换柱层析法分离纯化出莲藕多糖NPh1和NPh2,凝胶过滤柱色谱及高效液相色谱仪检测多糖纯度,证明NPh2为纯品,其相对分子量>2000kD,是一种酸性杂多糖,单糖组成为半乳糖,阿拉伯糖、鼠李糖、葡萄糖、岩藻糖和木糖,摩尔比依次为:26.74;16.17:5.69:5.49:2.31:1。利用碱化学法提取不溶性膳食纤维NDFh,得率为26.97%。用2.0%H2O2进行了脱色。NDFh的持水性和溶胀性分别为7.58g/g和9.0ml/g。

绿色木霉发酵制备黄豆渣膳食纤维的研究

本文以黄豆渣为原料、绿色木霉为菌种,制备水溶性含量高的膳食纤维,采用L16(45)正交试验对前发酵过程工艺条件展开了研究。试验表明,最佳工艺条件是:发酵液初始pH值5,发酵时间108h,发酵温度32℃,装液量115mL/250mL,接种量10%。通过前后二次发酵,总膳食纤维的得率为50.13%,水溶性膳食纤维(SDF)得率为12.03%,SDF约占总膳食纤维(DF)的24%,增加了黄豆渣膳食纤维中SDF含量。产品颗粒细小、均匀、色泽淡黄、口感细腻,持水力为10.31g·g-1,膨胀力为11.21mL·g-1。

超微粉碎对脱脂米糠膳食纤维理化特性及组成成分的影响

采用超微粉碎对脱脂米糠膳食纤维进行处理,研究不同粒径的纤维粉体的理化特性及组成成分的变化。实验结果表明,随着超微粉碎程度的加强,粒径的不断减小,膳食纤维的持水力、持油力、膨胀力均有显著提高,而阳离子交换能力先增加后降低;膳食纤维经超微粉碎后,纤维素含量基本保持不变,而部分半纤维素转化为水溶物。