Viscosity as related to dietary fiber: a review

Viscosity is a physicochemical property associated with dietary fibers, particularly soluble dietary fibers. Viscous dietary fibers thicken when mixed with fluids and include polysaccharides such as gums, pectins, psyllium, and beta-glucans. Although insoluble fiber particles may affect viscosity measurement, viscosity is not an issue regards insoluble dietary fibers. Viscous fibers have been credited for beneficial physiological responses in human, animal, and animal-alternative in vitro models. The following article provides a review of viscosity as related to dietary fiber including definitions and instrumentation, factors affecting viscosity of solutions, and effects of viscous polysaccharides on glycemic response, blood lipid attenuation, intestinal enzymatic activity, digestibility, and laxation.     

特殊纤维素在酸奶中的作用与应用

<正> 酸奶是通过利用纯净柔和且带乳酸香味的专用乳酸菌发酵剂对牛奶进行有控制性的发酵而成。在发酵时,牛奶中的乳糖会被乳杆菌属转化成乳酸,并产生双乙酰,直至酸度达pH 4.7～4.3。     

Inulin and oligofructose as fat and sugar substitutes in quick breads (scones): a mixture design approach

Mixture (D-optimal) design was used to investigate the effects of prebiotics such as inulin and oligofructose as fat and sugar replacers on quality parameters of quick breads (scones). Crust and crumb colour increased with the inclusion of prebiotics. Higher concentration of inulin and oligofructose in quick breads also showed a slight increase in crust and crumb hardness. Loaf volume significantly increased with the inclusion of prebiotics. The optimization tool indicated that by using a mixture of margarine (3.53%), oligofructose Orafti^? L95 (10%), caster sugar (0.55%) and inulin Orafti^? GR (5.92%), a quick bread with similar baking properties and textural attributes to the control can be achieved. The mixture design was successfully used to reduce the original levels of 10% fat and 10% sugar (percentages are based on flour weight). The calculated model performance indices accuracy factor and bias factor of the predicted quick-bread formulations showed a high applicability of the model. The variations between the predicted and experimental values obtained were within the acceptable error range, as depicted by the average mean deviation. Therefore, the predictive performance of the established model may be considered acceptable.     

Dietary fiber,inulin, and oligofructose: A review comparing their physiological effects

Dietary fiber is a general terra. It covers a wide variety of substances that belong to the family of carbohydrates that resist hydrolysis by human alimentary enzymes but are fermented by colonie microflora.

The main physiological effects of dietary fiber are primarily on gastric emptying and small intestinal transit time, resulting in an improved glucose tolerance and a decreased digestion of starch; second, on colonie transit time and large bowel functions due to fermentation by ceco‐colonic microbial flora or bulking action.

The so‐called soluble dietary fibers are fermented to a large extent by a wide variety of anaerobic bacteria that result in an increase in bacterial biomass, an increase in fecal mass, a change in intracolonic pH, and production of short chain fatty acids and various gases as metabolic end products. The insoluble fibers are only marginally fermented; they serve almost exclusively as bulking agents that result in shorter transit time and increased fecal mass.

The short chain fatty acids resulting from the colonie fermentation of dietary fiber are largely absorbed via the portal blood and reach both the liver and the peripheral tissues. They induce changes in glucose and fat metabolism leading to post‐prandial hypoglycemia and long‐term hypolipidemia.

Inulin and oligofructose are fructans with a degree of polymerization of 2 to 60 and 2 to 20. respectively. Due to the structural conformation of their osidic bridge ((3 2–1), they both resist the hydrolysis by human alimentary enzymes. Moreover, when reaching the colon, both inulin and oligofructose are almost quantitatively fermented almost exclusively by colonie bifidobacteria and bacteroides. Such an extensive fermentation causes an increase in fecal bacterial biomass, a decrease in ceco‐colonic pH. and produces a large amount of fermentation products among which the short chain fatty acids that exert systemic effects on lipid metabolism.

Thus, both inulin and oligofructose have most of the characteristics of a dietary fiber and the proposal is made to classify them as such. Moreover, they are bifidogenic factors, because, due to still unknown reasons, they are primarily fermented by bifidobacteria.

It is concluded from this review that “nondigestible fructooligosaccharides.” even though they arc not included in the carbohydrate fraction that is quantified as dietary fiber by classic analytical methods, have most of the physiological effects of a dietary fiber. Because it has become necessary for the consumer to be informed clearly and specifically on the nature and the beneficial effects of all fermentable carbohydrates that will “feed” their colon, it is suggested that food labeling should be extended to include such products in the dietary liber fraction.     

Alginate as a source of dietary fiber

Alginate, an algal polysaccharide, is widely used in the food industry as a stabilizer, or as a thickening or emulsifying agent. As an indigestible polysaccharide, alginate may also be viewed as a source of dietary fiber. Previous work has suggested that dietary fibres may protect against the onset and continuation of a number of cardiovascular and gastrointestinal diseases. This article aims to examine what is currently understood about the fiber-like activities of alginate, particularly its effects on intestinal absorption and the colon, and therefore aims to gauge the potential use of alginate as a dietary supplement for the maintenance of normal health, or the alleviation of certain cardiovascular or gastrointestinal diseases.     

香蕉膳食纤维的研究进展

概述香蕉膳食纤维（DF）的成分及功能，着重介绍其中的抗性淀粉，比较3种香蕉DF的含量以及贮藏过程中蕉皮DF的变化情况，简介香蕉膳食纤维的加工现状。     

膳食纤维聚葡萄糖的生理功能研究进展

本文主要介绍了聚葡萄糖的生理功能及其在食品中的应用特性.聚葡萄糖是一种难消化性碳水化合物,属于水溶件膳食纤维.诸多研究表明它具有良好的生理功能,因难以被人体消化利用而具有较低的能量,可调节肠道菌群的平衡,维持健康的肠道功能、防止便秘;提高免疫力,促进矿物质吸收,改善脂质代谢,降低血糖和控制体重等.聚葡萄糖具有高度的安全性和稳定的加工特性,不但可以用于食品的纤维强化,还能够改善食品的质构和口感,已被广泛应用于饮料、乳品、焙烤、糖果等各种食品及保健品中.     

Inulin and oligofructose improve sensory quality and increase the probiotic viable count in potentially synbiotic petit-suisse cheese

The influence of inulin, oligofructose and oligosaccharides from honey, combined in different proportions, on the consumers’ sensory acceptance, probiotic viable count and fructan content of novel potentially synbiotic petit-suisse cheeses was investigated. Probiotic populations varied from 7.20 up to 7.69 log cfu g⁻¹ (Bifidobacterium animalis subsp. lactis) and from 6.08 up to 6.99 log cfu g⁻¹ (Lactobacillus acidophilus). The highest fructan contents were achieved by the cheese trials containing oligofructose and/or inulin (above 8.90 g 100 g⁻¹). The control trial showed the lowest mean acceptance (6.63) after 28 days of refrigerated storage, whereas the highest acceptance (7.43) was observed for the trial containing 10 g 100 g⁻¹ oligofructose. Acceptance increased significantly during storage (P<0.05) only for cheeses supplemented with oligofructose and/or inulin. Cheeses containing honey did not perform well enough compared to the cheeses with addition of inulin and/or oligofructose, and the best synbiotic petit-suisse cheese considering sensory and technological functional features was that containing oligofructose and inulin combined, therefore encouraging the commercial product use.     

Nutritional responses to the presence of inulin and oligofructose in the diets of domesticated animals: a review

Inulin and oligofructose are prebiotic oligosaccharides fermented in the large intestine. This article provides an extensive review of the effects of these oligosaccharides on gastrointestinal characteristics (microflora, pathogen control, epithelial cell proliferation, putrefactive compound production, fecal characteristics, and nutrient digestibility) and systemic metabolism of carbohydrates, nitrogen, lipids, and minerals in dogs, cats, horses, calves, pigs, poultry, and rabbits. In addition, intake of inulin and oligofructose and considerations in their supplementation to animal diets are discussed. Growth performance and meat production in livestock in response to inulin and oligofructose supplementation are addressed. Finally, the possible substitution of antibiotics with fructans in animal diets and directions for future research are presented.     

Lemon albedo as a new source of dietary fiber: Application to bologna sausages

The aim of this work was to study the effect of the addition of lemon albedo in bologna sausages. Two types of albedo (raw and cooked) and five concentrations (0%, 2.5%, 5%, 7.5% and 10%) were added to sausages. Chemical, physicochemical and sensory analyses were made. The addition of albedo to bologna sausages represents an improvement in their nutritional properties and may have beneficial effects, possibly due to the presence of active biocompounds which induce a decrease in residual nitrite levels. The formulations which gave products with sensory properties similar to conventional sausages were sausages with 2.5% and 5% raw albedo and 2.5%, 5% and 7.5% cooked albedo.     

Invited review: Role of physically effective fiber and estimation of dietary fiber adequacy in high-producing dairy cattle

Highly fermentable diets require the inclusion of adequate amounts of fiber to reduce the risk of subacute rumen acidosis (SARA). To assess the adequacy of dietary fiber in dairy cattle, the concept of physically effective neutral detergent fiber (peNDF) has received increasing attention because it amalgamates information on both chemical fiber content and particle size (PS) of the feedstuffs. The nutritional effects of dietary PS and peNDF are complex and involve feed intake behavior (absolute intake and sorting behavior), ruminal mat formation, rumination and salivation, and ruminal motility. Other effects include fermentation characteristics, digesta passage, and nutrient intake and absorption. Moreover, peNDF requirements depend on the fermentability of the starch source (i.e., starch type and endosperm structure). To date, the incomplete understanding of these complex interactions has prevented the establishment of peNDF as a routine method to determine dietary fiber adequacy so far. Therefore, this review is intended to analyze the quantitative effects of and interactions among forage PS, peNDF, and diet fermentability with regard to rumen metabolism and prevention of SARA, and aims to give an overview of the latest achievements in the estimation of dietary fiber adequacy in high-producing dairy cattle. Recently developed models that synthesize the effects of both peNDF and fermentable starch on rumen metabolism appear to provide an appropriate basis for estimation of dietary fiber adequacy in high-producing dairy cows. Data suggest that a period lasting more than 5 to 6h/d during which ruminal pH is <5.8 should be avoided to minimize health disturbances due to SARA. The knowledge generated from these modeling approaches recommends that average amounts of 31.2% peNDF inclusive particles >1.18mm (i.e., peNDF(>1.18)) or 18.5% peNDF inclusive particles >8mm (i.e., peNDF(>8)) in the diet (DM basis) are required. However, inclusion of a concentration of peNDF(>8) in the diet beyond 14.9% of diet DM may lower DM intake level. As such, more research is warranted to develop efficient feeding strategies that encourage inclusion of energy-dense diets without the need to increase their content in peNDF above the threshold that leads to lower DM intake. The latter would require strategies that modulate the fermentability characteristics of the diet and promote absorption and metabolic capacity of ruminal epithelia of dairy cows.     

The influence of dietary inulin and oligofructose on the cell-mediated and humoral immunity in rats

This paper reviews evidence for the immune-enhancing effects of prebiotics. The influence of inulin and oligofructose on the immune functions and the structure of immune peripheral organs in male Wistar rats was investigated after 4 months feeding. Rats fed isocaloric purified diets contained 10% inulin or oligofructose. The rats of control group had no feeding any prebiotics. The enlargement of a number of T-cells and increasing of major histocompatibility complex (MHC-II) molecule on the surface of an antigen-presenting cells of spleen, mesenteric lymph nodes, thymus was noted. The increasing of content interleukin-2 and interleukin-4 in blood was noted in rats fed inulin and oligofructose. The increased activity of peritoneal macrophages was confirmed by enhance superoxid anion production and phagocytosis. The dietary prebiotics do not influence on the apoptosis of immunocytes. The immune-enhancing effects of prebiotics was confirmed by morphological investigation of peripheral lymphoid organs.     

聚葡萄糖作为水溶性膳食纤维的发展及法规现状

本文介绍了聚葡萄糖产品的历史及随应用需要而发展的产品品种,简要介绍了膳食纤维的定义,与粗纤维的分别以及分类.并根据定义以及分类将聚葡萄糖作为水溶性膳食纤维进行归类.聚葡萄糖在众多国家被认可为膳食纤维及食品添加剂或食品,本文介绍了聚葡萄糖作为膳食纤维被认可的国家以及相关规定,聚葡萄糖作为食品添加剂在各国的规定,聚葡萄糖作为膳食纤维的检测方法发展历史,同时介绍了聚葡萄糖在国内的法规现状及进展.聚葡萄糖不仅是一种水溶性膳食纤维,同时还是一种良好的Oligo益生元,本文介绍了Oligo(欧力多)低聚糖项目的情况以及功能性低聚糖通用技术规则,行业标准的相关定义,详细介绍聚葡萄糖符合各项定义的特性及作为膳食纤维及Oligo益生元的生理功效.     

Reduced calorie emulsion-based foods: Protein microparticles and dietary fiber as fat replacers

The potential of using microparticulated whey protein (MWP) in combination with either modified starch or locust bean gum (LBG) as fat mimetics to fabricate reduced calorie emulsion-based sauces and dressings was studied. The influence of food matrix composition (protein, polysaccharide, and fat content), ionic strength, and pH on the properties of thermally processed model emulsions (90 °C/10 min) was investigated. Increasing protein concentration (2.5–7.5%) increased the mean (d_3,2) particle diameter due to the formation of large protein aggregates. All MWP-containing systems had a creamy white appearance with high lightness (L* > 75). Addition of fat droplets (5%) further increased their lightness (L* > 90) due to enhanced light scattering. Addition of starch, LBG, or MWP increased emulsion viscosity due to the increased effective volume fraction of the dispersed phase. Addition of calcium chloride (10 mM) and pH adjustment (2–8) caused little change in the physicochemical properties of the mixed systems. Overall, the appearance and rheological properties of the mixed systems were similar to commercial sauces and dressings. This study demonstrates that reduced calorie food emulsions with appearance and consistency similar to those of full-fat versions can be formulated using protein microparticles and polysaccharides.     

Synthesis of Cyanoethyl Inulin,Aminopropyl Inulin and Carboxyethyl Inulin

Inulin was cyanoethylated by reaction with acrylonitrile in the presence of aqueous sodium hydroxide. Products with a degree of substution (ds) from 0.2 to 1.6 were prepared. The materials were analyzed using NMR spectroscopy and GPC analysis. The nitrile groups of cyanoethyl inulin were converted into amino groups by reduction with sodium borohydride in the presence of a transition metal chloride (CoCl₂.6H₂O). Furthermore, the nitrile groups were hydrolyzed towards carboxylates using hydrogen peroxide in alkaline medium. The polycarboxylate obtained by this means was shown to possess good calcium carbonate crystallization inhibition properties.     

膳食纤维测定仪测定食品中膳食纤维

目的利用膳食纤维测定仪测定食品中膳食纤维。方法以国家标准GB 5009.88-2014中酶-重量法为依据,样品在膳食纤维仪上经酶解处理、乙醇沉淀、洗涤抽滤得残渣,残渣干燥称重,再扣除膳食纤维残渣中的蛋白质、灰分和试剂空白即为样品中的膳食纤维。结果本方法检测不同食品中总膳食纤维、可溶性或不溶性膳食纤维,其重复性相对标准偏差(relative standard deviation,RSD)(n=6)分布在0.01%~7.81%之间,重现性RSD值(n=3)在1.15%~1.22%,回收率在95.7%~101.1%之间。结论采用膳食纤维测定仪进行测定集在线酶解、恒温、加热、洗涤抽滤于一体,操作简便,结果准确,适用于食品中膳食纤维的测定。     

Management of hyperuricemia through dietary polyphenols as a natural medicament: A comprehensive review

Hyperuricemia, a condition due to high serum uric acid level and is notorious to health. It is considered to be a potent risk factor for gout and dramatically associated in the development of many chronic diseases such as malignant tumor, cardiovascular disorders and renal failure. Modern innovative medicinal and therapeutic interventions are underlying these days to combat hyperuricemia. Previously reported studies revealed the significant impact of dietary polyphenols (e.g. anthocyanins, phenolic acids, flavonoids etc.) against hyperurecemia disorder. Dietary plant polyphenols, unlike anti- hyperuricemic agents, are not reported to have any side effects in curing hyperuricemia. The current comprehensive review figure outs the use of dietary polyphenols as a natural remedy for the management of hyperuricemia. The sources, affiliated pathways, mode of actions and factors affecting their efficiency to prevent hyperuricemia are deeply discussed in this article. Additionally, limitations and suggestions regarding previously reported studies are also highlighted.     

Natural and low-caloric rebaudioside A as a substitute for dietary sugars: A comprehensive review

For health and safety concerns, traditional high-calorie sweeteners and artificial sweeteners are gradually replaced in food industries by natural and low-calorie sweeteners. As a natural and high-quality sugar substitute, steviol glycosides (SvGls) are continually scrutinized regarding their safety and application. Recently, the cultivation of organic stevia has been increasing in many parts of Europe and Asia, and it is obvious that there is a vast market for sugar substitutes in the future. Rebaudioside A, the main component of SvGls, is gradually accepted by consumers due to its safe, zero calories, clear, and sweet taste with no significant undesirable characteristics. Hence, it can be used in various foods or dietary supplements as a sweetener. In addition, rebaudioside A has been demonstrated to have many physiological functions, such as antihypertension, anti-diabetes, and anticaries. But so far, there are few comprehensive reviews of rebaudioside A. In this review article, we discuss the physicochemical properties, metabolic process, safety, regulatory, health benefits, and biosynthetic pathway of rebaudioside A and summarize the modification methods and state-of-the-art production and purification techniques of rebaudioside A. Furthermore, the current problems hindering the future production and application of rebaudioside A are analyzed, and suggestions are provided.