Technological benefits of inulin-type fructans application in gluten-free products – A review

Impact of Flammulina velutipes polysaccharide on properties and structural changes of pork myofibrillar protein during the gel process in the absence or presence of oxidation

The present study aimed to investigate the impact of Flammulina velutipes polysaccharide (FVSP) on the rheological properties and structural alterations of myofibrillar protein (MP) and oxidized MP (OMP), utilizing techniques such as rhehometer, fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). In the unoxidized system, the addition of 5.00% FVSP significantly improved (p < 0.05) the storage and loss moduli of the composite gel and promoted the α-helix to β-sheet transformation. These effects enhanced the protein's gel strength and water-holding capacity (WHC). In the oxidation system, 5.00% FVSP had significant effects (p < 0.05) on repair and improvement of the oxidized MP. These effects inhibited the cross-linking aggregation and degradation of the protein. In addition, the addition of FVSP significantly improved the gel properties of MPs after oxidation (p < 0.05), hindered fracture of the protein gel network structure. In summary, polysaccharides have a substantial effect on the functional characteristics of MP, and FVSP could potentially be applied in meat products.

Gluten-free Nan-e-Fasaee: Formulation optimization on the basis of quinoa flour and inulin

Diversification of gluten-free (GF) bakery products is considerably important, as those who suffer from gluten intolerance should follow a GF diet their whole life. Regarding this study, it was aimed at optimizing the formulation of a quinoa-based GF traditional bakery product, i.e. Nan-e-Fasaee using inulin as a bifunctional agent (both a prebiotic compound and a structure-forming agent). Otherwise, its potential role as a fat and sugar replacer was also assessed. For this purpose, short (S)- and long (L)-chain inulin were used as sugar and fat replacers, respectively, at 0%-50% w/w in quinoa flour (QF)-based GF Nan-e-Fasaee and optimization was done based on rheological, textural, and sensory analysis. Results indicated that QF diet provided the batter with the dominance of elastic modulus and increased hardness (i.e. 5170.0 ± 22.50 g in the presence of QF compared to 1477.0 ± 20.81 g in wheat-based ones). Inulin inclusion reduced the hardness, as the lowest was observed at S-inulin substitution levels of 40% and 50% w/w, with values equal to 2422.0 ± 20.81 and 2431.0 ± 35.57 g, respectively (the most similar ones to control sample). The interference of S-inulin with the non-gelatinized starch structure is supposed to decrease the hardness. The highest score in texture was also perceived at F6 and F13, with values equal to 8.00 ± 0.10 and 7.97 ± 0.05, respectively. Using S- and L-inulin in combination is found to improve the textural characteristics due to preventing the competitive role of sugar in water absorption in formulations containing L-inulin. Regarding optimization of quinoa-based GF Nan-e-Fasaee with reduced sugar and fat levels using inulin, it is found to be feasible.

Retrogradation behavior of starch dough prepared from damaged cassava starch and its application in functional gluten-free noodles

A novel starch-based model dough used to exploit staple foods was demonstrated to be feasible, which was based on damaged cassava starch (DCS) obtained by mechanical activation (MA). This study focused on the retrogradation behavior of starch dough and the feasibility of its application in functional gluten-free noodles. Starch retrogradation behavior was investigated by low field-nuclear magnetic resonance (LF-NMR), X-ray diffraction (XRD), scanning electron microscope (SEM), texture profile and resistant starch (RS) content analysis. During starch retrogradation, water migration, starch recrystallization and microstructure changes were observed. Short-term retrogradation could significantly alter the texture properties of starch dough, and long-term retrogradation promoted the formation of RS. The damage level influenced starch retrogradation, and damaged starch with the increasing damage level was beneficial to facilitate the starch retrogradation. Gluten-free noodles made from the retrograded starch had acceptable sensory quality, with darker color and better viscoelasticity than Udon noodles. This work provides a novel strategy for the proper utilization of starch retrogradation for the development of functional foods.

Salt stress affects the biomass of industrial crop Jerusalem artichoke by affecting sugar transport and metabolism

Even though Jerusalem artichoke (Helianthus tuberosus L.) has strong resistance to abiotic stresses, salinity can still reduce the biomass of Jerusalem artichoke. The purpose of this study was to elucidate the differences in the development of Jerusalem artichoke and the dynamics of sugar throughout the growth period under high (7.23-8.15 g/kg) and low (3.20-4.32 g/kg) salinity stress in the field in Jiangsu Province, China. This study confirmed that high salinity promoted the conversion of reducing sugars to non-reducing sugars (fructans) in Jerusalem artichoke tubers, but significantly reduced the biomass of Jerusalem artichoke and advanced the peak time of the dry matter accumulation of aerial parts. In addition, in the early and late stages of tuberization, the total sugar content of tubers under low salinity conditions (786 ± 8 mg/g and 491 ± 8 mg/g) was 93.3% and 1.15 times than those under high salinity conditions, respectively. Moreover, the total sugar content in stems was consistently greater under high than low salinity conditions in the same period. The accumulation rate and the amount of dry matter were significantly higher in stems than in other tissues. Therefore, the aerial parts of "Nanyu No. 1" could be harvested before mid-to-early October, and the tubers after mid-November. This study revealed the internal reasons for the decreased yield of Jerusalem artichoke under salt stress, and provided theoretical basis and guidance for the cultivation and utilization of Jerusalem artichoke in saline-alkali soil.

Characterization of a processive inulosucrase from Lactobacillus mulieris for efficient biosynthesis of high-molecular-weight inulin

Inulin has been determined to have many exceptional properties and functions and has been used in the food and pharmaceutical fields. Recently, microbial high-molecular-weight inulin synthesized from sucrose by inulosucrase attracted much attention. In this study, a novel inulosucrase from Lactobacillus mulieris was constructed, overexpressed, purified, and identified. The recombinant enzyme displayed the maximum activity at pH 6.0 and 55 °C, and it exhibited high thermostability below 45 °C. After optimizing the production conditions, the conversion rate from 100 g/L sucrose to inulin reached 31 %, meanwhile, the maximum molecular weight of produced inulin reached 3.21 × 10⁶ g/mol. The truncated IS showed a "processive" transfructosylation process, only synthesizing a small number of short-chain oligosaccharides with polymerization degrees below 6, which was in favor of the accumulation of high-molecular-weight inulin. Given this, L. mulieris inulosucrase might be a good potential candidate for the industrial production of high-molecular-weight inulin.

Application of inulin in bread: A review of technological properties and factors affecting its stability

Due to its dual function, inulin is an important prebiotic compound in the cereal industry, especially in bread production. In other words, improving technological features and creating health properties (such as reducing the risk of type 2 diabetes, heart disease, metabolic syndrome, and osteoporosis) have led to the widespread use of this compound. Inulin has many important technological functions in bread, including its ability to interact with water, create structure, and influence rheological properties, texture, and overall acceptability of the final product. Nevertheless, bread processing conditions can influence the structural integrity of inulin and thus affect its technological efficiency. Therefore, this review article aims to investigate the technological properties and factors affecting the stability of inulin during bread processing conditions. Generally, the addition of inulin could considerably improve the technical performance of bread. However, the stability of inulin depends on the formulation components, type of fermentation, and baking process.

Overview of the Importance of Biotics in Gut Barrier Integrity

Increased gut permeability is suggested to be involved in the pathogenesis of a growing number of disorders. The altered intestinal barrier and the subsequent translocation of bacteria or bacterial products into the internal milieu of the human body induce the inflammatory state. Gut microbiota maintains intestinal epithelium integrity. Since dysbiosis contributes to increased gut permeability, the interventions that change the gut microbiota and correct dysbiosis are suggested to also restore intestinal barrier function. In this review, the current knowledge on the role of biotics (probiotics, prebiotics, synbiotics and postbiotics) in maintaining the intestinal barrier function is summarized. The potential outcome of the results from in vitro and animal studies is presented, and the need for further well-designed randomized clinical trials is highlighted. Moreover, we indicate the need to understand the mechanisms by which biotics regulate the function of the intestinal barrier. This review is concluded with the future direction and requirement of studies involving biotics and gut barrier.

Gluten-Free Bread and Bakery Products Technology

Gluten, a protein fraction from wheat, rye, barley, oats, their hybrids and derivatives, is very important in baking technology. The number of people suffering from gluten intolerance is growing worldwide, and at the same time, the need for foods suitable for a gluten-free diet is increasing. Bread and bakery products are an essential part of the daily diet. Therefore, new naturally gluten-free baking ingredients and new methods of processing traditional ingredients are sought. The study discusses the use of additives to replace gluten and ensure the stability and elasticity of the dough, to improve the nutritional quality and sensory properties of gluten-free bread. The current task is to extend the shelf life of gluten-free bread and bakery products and thus extend the possibility of its distribution in a fresh state. This work is also focused on various technological possibilities of gluten-free bread and the preparation of bakery products.

Delving into the Role of Dietary Fiber in Gluten-Free Bread Formulations: Integrating Fundamental Rheological, Technological, Sensory, and Nutritional Aspects

The evidenced relevance of dietary fibers (DF) as functional ingredients shifted the research focus towards their incorporation into gluten-free (GF) bread, aiming to attain the DF contents required for the manifestation of health benefits. Numerous studies addressing the inclusion of DF from diverse sources rendered useful information regarding the role of DF in GF batter’s rheological properties, as well as the end product’s technological and nutritional qualities. The presented comprehensive review aspires to provide insight into the changes in fiber-enriched GF batter’s fundamental rheological properties, and technological, sensory, and nutritional GF bread quality from the insoluble and soluble DF (IDF and SDF) perspective. Different mechanisms for understanding IDF and SDF action on GF batter and bread were discussed. In general, IDF and SDF can enhance, but also diminish, the properties of GF batter and bread, depending on their addition level and the presence of available water in the GF system. However, it was seen that SDF addition provides a more homogenous GF batter structure, leading to bread with higher volumes and softer crumb, compared to IDF. The sensory properties of fiber-enriched GF breads were acceptable in most cases when the inclusion level was up to 7 g/100 g, regardless of the fiber type, enabling the labeling of the bread as a source of fiber.

Sourdough Biotechnology Applied to Gluten-Free Baked Goods: Rescuing the Tradition

Recent studies suggest that the beneficial properties provided by sourdough fermentation may be translated to the development of new GF products that could improve their technological and nutritional properties. The main objective of this manuscript is to review the current evidence regarding the elaboration of GF baked goods, and to present the latest knowledge about the so-called sourdough biotechnology. A bibliographic search of articles published in the last 12 years has been carried out. It is common to use additives, such as hydrocolloids, proteins, enzymes, and emulsifiers, to technologically improve GF products. Sourdough is a mixture of flour and water fermented by an ecosystem of lactic acid bacteria (LAB) and yeasts that provide technological and nutritional improvements to the bakery products. LAB-synthesized biopolymers can mimic gluten molecules. Sourdough biotechnology is an ecological and cost-effective technology with great potential in the field of GF products. Further research is necessary to optimize the process and select species of microorganisms robust enough to be competitive in any circumstance.

Chicory (Cichorium intybus L.) as a food ingredient - Nutritional composition, bioactivity, safety, and health claims: A review

Chicory (Cichorium intybus L.) is a perennial herb from the Cichorium genus, Asteraceae family, and is worldwide cultivated. So far, chicory has been used mainly in animal feed, but also in several cases in the food industry: as salad, for teas and tea blends, for coffee supplementation, and as a source for the inulin production. Nowadays there is an increasing interest in chicory utilization for food production and supplementation. Some compounds present in chicory, such as polyphenols, inulin, oligofructose and sesquiterpene lactones may be considered as potential carriers of food functionality. This review describes nutritional, mineral and bioactive composition of the chicory plant and summarized the main biological activities associated with the presence of bioactive compounds in the different plant parts. Finally, the review explores possibilities of uses of chicory and its implementation in food products, with intention to design new functional foods.

High-Quality Gluten-Free Sponge Cakes without Sucrose: Inulin-Type Fructans as Sugar Alternatives

Due to its structural and organoleptic functions, sucrose is one of the primary ingredients of many baked confectionery products. In turn, the growing awareness of the association between sugar overconsumption and the development of chronic diseases has prompted the urgent need to reduce the amount of refined sugar in foods. This study aimed to evaluate the effect of complete sucrose replacement with inulin-type fructans (ITFs), namely fructooligosaccharide (FOS), inulin (INU) or oligofructose-enriched inulin (SYN), with different degrees of polymerization on the technological parameters and sensory quality of gluten-free sponge cakes (GFSs). The use of ITFs as the sole sweetening ingredient resulted in the similar appearance of the experimental GFSs to that of the control sample. In addition, all GFSs containing ITFs had similar height, while their baking weight loss was significantly (p < 0.05) lower compared to the control products. The total sugar exchange for long-chain INU increased the crumb hardness, while the crumb of the GFS with FOS was as soft as of the control products. The sensory analysis showed that the GFS containing FOS obtained the highest scores for the overall quality assessment, similar to the sugar-containing control sponge cake. The results obtained prove that sucrose is not necessary to produce GFSs with appropriate technological parameters and a high sensory quality. Thus, it can be concluded that sucrose can be successfully replaced with ITF, especially with FOS, in this type of baked confectionery product.

Textural and Sensory Features Changes of Gluten Free Muffins Based on Rice Sourdough Fermented with Lactobacillus spicheri DSM 15429

Gluten free products available on the market have a low textural quality associated with high crumbly structure, low-flavor, aroma, poor mouthfeel, less appearance, in comparison with the conventional final baked products. The aim of this study was to assess the influence of rice sourdough fermented with Lactobacillus spicheri DSM 15429 strain on textural, volatile profile, and sensorial properties of gluten free muffins in order to obtain baked goods with improved quality characteristics. Lactobacillus spicheri is a novel strain isolated from industrial rice sourdough but unexploited for bakery products manufacturing. The results showed that Lactobacillus spicheri DSM 15429 was able to growth in the rice flour influencing the texture and the volatile profile of gluten free muffins as well as their sensory characteristics. Both, textural parameters and volatiles recorded significant differences comparing to muffins obtained with a spontaneously fermented rice sourdough. Hardness and cohesiveness decreased while springiness and resilience of gluten free muffins improved their values. The volatile profile of gluten free muffins was significantly improved by utilization of the rice sourdough fermented with Lactobacilus spicheri DSM 15429. 3-methylbutanal, 2-methylbutanal, acetophenone and limonene were the main volatile derivatives responsible for aroma and odor scores of sensory analysis.

Thermal Properties of Semolina Doughs with Different Relative Amount of Ingredients

The impact of the relative amount of ingredients, wheat variety, and kneading time on the thermal properties of semolina doughs were investigated by means of thermogravimetric analysis (TGA). The doughs were prepared by mixing water, semolina, yeast, and salt in different proportions. The gelatinized flour fraction plays an important role in the thermal properties’ definition, while the water amount influences the development of the dough network and, consequently, the starch gelatinization phenomena. Furthermore, the amount of yeast and salt influences the dough network force and, consequently, the thermal properties. The TGA technique was applied in order to evidence the mass loss as a function of the increasing temperature, considering that this behavior depends on the dough network force and extension. In such a way, it was possible to find some information on the relationship between the dough characteristics and the thermogravimetric analysis outputs. The study is devoted to acquiring deeper knowledge about the thermophysical characteristics of doughs in the breadmaking industrial processes, where the controllability and the energy performances need to be improved. A deeper knowledge of the dough properties, in terms of measurable parameters, could help to decrease the amounts of off-specification products, resulting in a much more energy-efficient and sustainable processing.

Characterization of Fructan Metabolism During Jerusalem Artichoke (Helianthus tuberosus L.) Germination

The inulin-type fructans in Jerusalem artichoke (Helianthus tuberosus L.) tubers exhibit different degrees of polymerization and are critical for germination. We aimed to characterize the sugar metabolism dynamics in the tubers without bud eyes or shoots (T) and BE/S of indoor- and field-grown Jerusalem artichokes during germination. Ht1-FEH II and Ht1-FEH III (1-fructan exohydrolases II and III, inulin-degrading enzymes) expression increased 5 days after planting indoors, whereas Ht1-FEH II expression increased 72 days after planting in the field in T and BE/S. Ht1-SST (sucrose:sucrose 1-fructosyl transferase, inulin synthesis initiator), and Ht1-FFT (fructan:fructan 1-fructosyl transferase, inulin elongator) expression generally decreased in indoor-grown T. The enzyme activities of 1-FEH and 1-FFT were unchanged during germination in both indoor- and field-grown T and BE/S, whereas 1-SST activity decreased in indoor-grown T, while 1-FEH and 1-FFT activities increased as a function of germination time in BE/S of both indoor- and field-grown tubers. The total soluble sugar content gradually decreased in T after germination indoors or in the field, while at the end of germination, the sucrose and fructan contents decreased, and fructose content increased in the field. The enzyme activities of soluble vacuolar (VI) or neutral invertase (NI) did not change significantly, except at the late germination stage. Sucrose synthase (SS) and sucrose-phosphate synthase (SPS) activities were not significantly changed in T and BE/S in indoor-grown artichokes, while SS activity gradually increased, and SPS activity gradually decreased in field-grown artichokes, alongside sucrose degradation. Compared to T, BE/S generally had higher enzyme activities of 1-FEH and 1-FFT, promoting inulin hydrolysis. This work shows that the process of tuber germination is similar indoors and in the field, and germination studies can therefore be conducted in either environment.

Improvement in freeze-thaw stability of rice starch gel by inulin and its mechanism

Three types of inulin with different degree of polymerization (average DP < 10, DP ≥ 10, and DP > 23) were used to improve the freeze-thaw stability of rice starch gel. The gels with or without addition of inulin were subjected to seven freeze-thaw cycles (FTC). Inulin enhanced the water holding capacity and reduced the amount of freezable water of the gels, thereby decreasing the syneresis of the gels during seven FTC. In addition, the amylose and amylopectin retrogradation of the gels were retarded. By adding inulin, the microstructure of gel network was stabilized, and the deterioration in viscoelastic properties of the gels during seven FTC was reversed. Therefore, inulin was an effective additive for preserving the quality of freeze-thawed rice starch gels. Furthermore, low DP inulin had higher water holding capacity than high DP one, as a result the inulin with lower DP was more effective.

Development of gluten-free muffins utilizing squash seed dietary fiber

Gluten-free muffins with squash seed flour (SSF) were developed for contribute to reduce nutritional deficiencies and improving the health of the celiac population. Physicochemical and sensory properties of muffins were evaluated. SSF was incorporated at two levels (10 and 20% w/w) in commercial gluten-free premix (control). Incorporation of SSF increased total dietary fiber content, protein and unsaturated fatty acids. The addition of SSF at 10% resulted in a muffin that did not differ significantly from the control muffin; and also that formulations with SSF at 20% caused an increase in the browning index. Browning was favored by the increase of SSF with higher levels of fiber content. Incorporation of SSF at 20% had a significant effect on the textural parameters (firmness and chewiness) of the muffin. Also, both formulations containing SSF showed a higher overall acceptability, particularly muffins with 20% of SSF that rendered the highest scores for sponginess, texture, taste and colour.

Chicory syrup as a substitution of sugar in fine pastry

Fine pastry is a favorite snack but contains big amount fats and sugars. Sugar consumption is a major factor in the development of diabetes and obesity. Because of the growing interest in low-calorie alternatives to sucrose, producers react with different new products which can replace sugar and do not compromise the consumer acceptability of food products. This study deals with replacement of sugar with chicory oligofructose syrup, which provides same sweetness as sugar but contain over 70 % of fiber. Chicory syrup is composed of oligo-fructose and inulin. Inulin-type fructans are beneficial for immune and cardiovascular systems and its prebiotic function can protect colon health. In this study, the influence of sucrose (7 g.100g-1) replacement with chicory oligofructose syrup (0; 3.5; 7 g.100g-1) on the texture, specific loaf volume and sensory acceptability of biologically leavened muffins was tested. The substitution of sugar by the chicory syrup decreased specific loaf volume from 2.15 to 2.01 mL.g-1 while hardness, springiness and chewiness increased. There was no detrimental impact of syrup addition to cohesiveness of fine pastry muffin. It was observed that due to the syrup addition, pastry hardens faster, as showed results of hardnesss measured after 24 h. Bread crumb and crust sensory characteristics were not affected by the syrup addition. Weak impact of sugar replacement on sensory evaluation may be related to a reduced amount of the panelists involved in this study. More extensive study will, however, be performed to describe the impact of sugar replacement of fine biologically leavened muffins in more details. The results of this preliminary study shows, that the substitution of sugar by chicory syrup change textural properties and loaf volume. Despite all, based on sensory analysis the chicory syrup up to amount 7 g.100g-1 seems to be adequate for its use as a sugar replacer in fine pastry as biologically leavened muffins.

Synthesis of inulin derivatives with quaternary phosphonium salts and their antifungal activity

Inulin is a kind of renewable and biodegradable carbohydrate with good water solubility and numerous physiological functions. For further utilization of inulin, chemical modification can be applied to improve its bioactivities. In this paper, five novel inulin derivatives were synthesized via chemical modification with quaternary phosphonium salt. Their antifungal activity against three kinds of plant pathogens including Colletotrichum lagenarium, Phomopsis asparagi, and Fusarium oxysporum was assessed with radial growth assay in vitro. Results revealed that all the inulin derivatives exhibited improved antifungal activity compared with inulin. Particularly, inulin modified with triphenylphosphine (TPhPAIL) exhibited the best antifungal activity with inhibitory indices of 80.0%, 78.8%, and 87.4% against Colletotrichum lagenarium, Phomopsis asparagi, and Fusarium oxysporum at 1.0mg/mL respectively. The results clearly showed that chemical modification of inulin with quaternary phosphonium salt could efficiently improve derivatives' antifungal activity. Further analysis of results indicated that the antifungal activity was influenced by alkyl chain length or electron-withdrawing ability of the grafted quaternary phosphonium salts. Longer alkyl chain lengths or the stronger electron-withdrawing groups would lead to enhanced antifungal efficacy.

The Effect of Oligofructose-Enriched Inulin on Faecal Bacterial Counts and Microbiota-Associated Characteristics in Celiac Disease Children Following a Gluten-Free Diet: Results of a Randomized, Placebo-Controlled Trial

Celiac disease (CD) is associated with intestinal microbiota alterations. The administration of prebiotics could be a promising method of restoring gut homeostasis in CD. The aim of this study was to evaluate the effect of prolonged oligofructose-enriched inulin (Synergy 1) administration on the characteristics and metabolism of intestinal microbiota in CD children following a gluten-free diet (GFD). Thirty-four paediatric CD patients (mean age 10 years; 62% females) on a GFD were randomized into two experimental groups receiving Synergy 1 (10 g/day) or placebo (maltodextrin; 7 g/day) for 3 months. The quantitative gut microbiota characteristics and short-chain fatty acids (SCFAs) concentration were analysed. In addition, side effects were monitored. Generally, the administration of Synergy 1 in a GFD did not cause any side effects. After the intervention period, Bifidobacterium count increased significantly (p < 0.05) in the Synergy 1 group. Moreover, an increase in faecal acetate and butyrate levels was observed in the prebiotic group. Consequently, total SCFA levels were 31% higher than at the baseline. The presented trial shows that Synergy 1 applied as a supplement of a GFD had a moderate effect on the qualitative characteristics of faecal microbiota, whereas it stimulated the bacterial metabolite production in CD children.

Functional Dehydrated Foods for Health Preservation

The market of functional foods has experienced a huge growth in the last decades due to the increased consumers’ awareness in a healthy lifestyle. Dried fruits constitute good snacks, in alternative to salty or sweet ones, and food ingredients due to their taste and nutritional/health benefits. Bioactive molecules are interesting sources to develop functional foods, as they play a major role in improving the health status and minimizing disease risks. The bioactive compounds most widely discussed in literature are presented in this review, for example, polyphenols, phytosterols, and prebiotics. Different technologies to dry bioproducts for producing functional foods or ingredients are presented. New drying techniques for the preservation of bioactive compounds are proposed, focusing more specifically on dielectric drying. A discussion on the techniques that can be used to optimize drying processes is performed. An overview on dehydrated plant based foods with probiotics is provided. The microorganisms used, impregnation procedures, drying methods, and evaluated parameters are presented and discussed. The principal bioactive compounds responsible for nutritional and health benefits of plant derived dried food products—fruits and vegetables, fruits and vegetables by-products, grains, nuts, and algae—are presented. Phytochemical losses occurring during pretreatments and/or drying processes are also discussed.

Administration of Inulin-Supplemented Gluten-Free Diet Modified Calcium Absorption and Caecal Microbiota in Rats in a Calcium-Dependent Manner

In coeliac disease (CD), the risk of adverse calcium balance and reduced bone density is induced mainly by the disease, but also by a gluten-free diet (GFD), the only accepted CD therapy. Prebiotics through the beneficial impact on intestinal microbiota may stimulate calcium (Ca) absorption. In the present study, we hypothesised that the dietary inulin in GFD would influence positively the intestinal microbiota, and by that will stimulate the absorption of calcium (Ca), especially in the conditions of Ca malnutrition. In a six-weeks nutritional experiment on growing a significant (p < 0.05) luminal acidification, decrease in ammonia concentration and stimulation of short chain fatty acids formation indicated inulin-mediated beneficial effects on the caecal microbiota. However, the effect of inulin on characteristics of intestinal microbiota and mineral utilization depended on the dietary Ca intake from GFDs. Inulin stimulated bifidobacteria, in particular B. animalis species, only if a recommended amount of Ca was provided. Most benefits to mineral utilization from inulin consumption were seen in rats fed Ca-restricted GFD where it increased the relative Ca absorption. Administration of inulin to a GFDs could be a promising dietary strategy for beneficial modulation of intestinal ecosystem and by that for the improvement the Ca absorption.

The quality of functional whole-meal durum wheat spaghetti as affected by inulin polymerization degree

The use of inulin in pasta improves the nutritional value decreasing the glycemic index in the blood after pasta ingestion but it compromises the sensory characteristics in terms of elasticity, firmness, bulkiness and adhesiveness. Thus, in this work, the impact of substituting whole-meal durum wheat flour with inulin on cooking quality, sensory and textural properties, digested starch and chemical composition of spaghetti was investigated. Two types of inulin at two different concentrations (2% and 4%) were adopted: inulin extracted from cardoon roots (CRI) (high polymerization degree) and commercial inulin (CHI) (low polymerization degree) produced from chicory. From the chemical point of view, the sample with 4% CRI showed the greatest total dietary fibres content and the lowest available carbohydrates content. A global acceptable quality was also recorded in all the other technological and sensory properties of enriched pasta with both types and both concentrations of inulin. The most feature of the work is that when CRI was added to the dough, better results were recorded, thus suggesting that for pasta enrichment, the selection of inulin with proper polymerization degree is a strategic factor for final product acceptance.