Quality of Gluten-Free Bread Formulations Baked in Different Ovens

Effect of Different Hydrocolloids on the Qualitative Characteristics of Fermented Gluten-Free Quinoa Dough and Bread

The aim of this research was to optimize the production process of fermented gluten-free quinoa bread. To this end, the effect of different hydrocolloids on the technological, fermentative, and nutritional properties of quinoa-based gluten-free doughs and breads was evaluated. For this purpose, 3% of four different hydrocolloids (sodium alginate, k-carrageenan, xanthan gum, and hydroxypropyl methylcellulose (HPMC)) were used in gluten-free doughs composed of 50% quinoa flour, 20% rice flour, and 30% potato starch. The rheological and fermentative properties of the doughs were evaluated, as well as the chemical composition, specific volume, crust and crumb color, and alveolar structure profile of gluten-free breads. The results highlighted the differences in dough rheology during mixing and fermentation of the doughs. In particular, HPMC showed a good gas retention (93%) during the fermentation of quinoa dough by registering the highest maximum dough development height (Hm). The gluten-free quinoa breads obtained were characterized by significantly different quality parameters (p < 0.05). The use of 3% HPMC resulted in breads with the lowest baking loss, the highest volume, and the most open crumb structure.

Bioprocessed Wholegrain Spelt Flour Improves the Quality and Physicochemical Characteristics of Wheat Bread

In the present study, the partial substitution of common white wheat flour for a bread recipe with variously bioprocessed wholegrain spelt was investigated. The addition of 1% and pasteurised 5% "germinated + enzymatic treated" spelt flour to wheat flour significantly improved the specific volume of the bread, but their texture profile analysis and sensory evaluation were not satisfactory. A higher percentage of added bioprocessed spelt flour darkened the colour of the bread. Breads with the addition of more than 5% of bioprocessed spelt flour were unacceptable in terms of quality and sensory parameters. The highest extractable and bound individual phenolics were found in breads with 5% "germinated + fermented" spelt flour (GFB5) and 5% pasteurised "germinated + enzymatic treated" spelt flour (GEB5P). A strong positive correlation was determined between trans-ferulic acid and TPC and DPPH^• radical scavenging activity. The GEB5P bread showed the highest increase in extractable and bound trans-ferulic acid content, by 320% and 137%, respectively, compared to the control bread. Principal component analysis showed differences between the control bread and enriched breads in terms of their quality, sensory and nutritional properties. Breads with 2.5% and 5% "germinated + fermented" spelt flour had the most acceptable rheological, technological and sensory characteristics, in addition to a substantial improvement in their antioxidant content.

Processing strategies to improve the breadmaking potential of whole-grain wheat and non-wheat flours

Strategies to increase the bio-functionality of staple food, such as bread, by incorporating whole-grain wheat flour or flour from other, non-wheat grains instead of refined wheat flour are often constrained with the lack of their techno-functionality, despite the associated beneficial effect on consumers' health and well-being. Most of the available studies investigating the possibilities to improve technological and sensory quality of bread prepared using whole-grain wheat and non-wheat flours still rely on formulation approaches in which different additives and novel ingredients are used as structuring agents. Less attention has been given to technological approaches which could be applied to induce structural changes on biopolymer level and thus increase the breadmaking potential of whole grains such as: modification of grain and biopolymers structure by germination, flour particle size reduction, dry-heat or hydrothermal treatment, atmospheric cold plasma, high-pressure processing or ultrasound treatment. Strategies to modify processing variables during breadmaking like dough kneading and hydration modification, sourdough fermentation or non-conventional baking techniques application are also poorly exploited for bread preparation from non-wheat grains. In this paper, the challenges and opportunities of abovementioned processing strategies for the development of bread with whole-wheat flours and non-wheat flours from underutilised gluten-containing or gluten-free cereals and pseudocereals will be reviewed throughout the whole breadmaking chain: from grain to bread and from milling to baking. Feasibility of different strategies to increase the technological performance and sensory quality of bread based on whole-grain wheat flours or flours from other, non-wheat grains will be addressed considering both the environmental, safety and nutritive advantages.

Significance of milling methods on brown teff flour, dough, and bread properties

Teff (Eragrostis tef) has gained wide popularity of late mainly attributed to its gluten-free nature catering the needs of gluten sensitive population. The higher water absorption capacity and gelling properties of teff flour promote its food applications, especially in the baking sector. The nutritional and sensorial properties of teff flour have been studied by incorporating with wheat flour at different proportions, but no study has reported the impact of various milling methods on the rheological and bread-making properties of teff flour. In this regard, the present study is envisaged to assess the physical, rheological and bread-making properties of teff flour acquired over roller, hammer and pin milling. Among the milling methods, the distribution of particles was more uniform in case of roller mill, while finer particles were obtained for the pin milled flour fractions with 60% of the sample falling below 90 μm. It was observed that the protein, crude fiber and crude fat contents for all the flours were on par with each other irrespective of the milling method. Whereas, the pasting properties varied significantly between the flours obtained from different milling methods. It was observed that the pin milled flour bread was superior in quality owing to its higher loaf volume (331.67 cm³ ) with lower hardness value (5.99 N). The present study indicates the fact that, pin mill could be more suitable for milling brown teff grains owing to the better pasting and bread making properties. This article is protected by copyright. All rights reserved.

Tiger Nut (Cyperus esculentus L.): Nutrition, Processing, Function and Applications

The tiger nut is the tuber of Cyperus esculentus L., which is a high-quality wholesome crop that contains lipids, protein, starch, fiber, vitamins, minerals and bioactive factors. This article systematically reviewed the nutritional composition of tiger nuts; the processing methods for extracting oil, starch and other edible components; the physiochemical and functional characteristics; as well as their applications in food industry. Different extraction methods can affect functional and nutritional properties to a certain extent. At present, mechanical compression, alkaline methods and alkali extraction-acid precipitation are the most suitable methods for the production of its oil, starch and protein in the food industry, respectively. Based on traditional extraction methods, combination of innovative techniques aimed at yield and physiochemical characteristics is essential for the comprehensive utilization of nutrients. In addition, tiger nut has the radical scavenging ability, in vitro inhibition of lipid peroxidation, anti-inflammatory and anti-apoptotic effects and displays medical properties. It has been made to milk, snacks, beverages and gluten-free bread. Despite their ancient use for food and feed and the many years of intense research, tiger nuts and their components still deserve further exploitation on the functional properties, modifications and intensive processing to make them suitable for industrial production.

Role of Hydrocolloids in the Structure, Cooking, and Nutritional Properties of Fiber-Enriched, Fresh Egg Pasta Based on Tiger Nut Flour and Durum Wheat Semolina

The aim of this work concerns the manufacturing process of fresh egg tagliatelle labeled as a "source of fiber" based on tiger nut flour and wheat semolina. An attempt to improve the quality attributes and cooking properties of the obtained product was made by means of structuring agents. More specifically, a combination of three hydrocolloids (carboximethylcellulose, CMC; xanthan gum, XG; and locust bean gum, LBG) was tested. A Box-Behnken design with randomized response surface methodology was used to determine a suitable combination of these gums to achieve fewer cooking losses, higher water gain and swelling index values, and better texture characteristics before and after cooking. Positive effects on textural characteristics were observed when incorporating XG into the pasta formulation. Cooking and fiber loss also significantly diminished with the XG-CMC combination over 0.8%. No significant effect was found for the other evaluated parameters. A synergistic interaction between LBG and XG was only significant for the water absorption index. The cooked pasta was considered a source of fiber in all cases.

Partial salt reduction in gluten-free chicken nugget extended with white button mushroom and quality development with eggplant flour

This study was investigated to develop healthy gluten-free chicken nuggets with less salt content and more nutrients using white button mushroom and eggplant flour. Nine nugget formulations, including three full-chicken nuggets with salt content [1% (control), 0.75%, and 0.5% w/w], and six chicken-white button mushroom (80: 20) nuggets with salt content (0.75%, and 0.5% w/w) and eggplant flour (0, 2.5% and 5% w/w) were examined. Physical properties on cooking yield, shrinkage, released fluid, firmness, and color scales (L*, a*, and b*) were analyzed. While sensory characteristics were evaluated using a 9-point hedonic scale. Reducing salt from 1 to 0.5% negatively affected the physical properties and sensory attributes of full-chicken formulations. There were no significant physical properties changes, except for color between full-chicken and chicken-mushroom nuggets. At the same time, their sensory characteristics were comparable. The addition of eggplant flour improved the physical parameters in reduced-salt nuggets and texture acceptability but deteriorated other sensory attributes. In conclusion, the addition of 2.5% eggplant flour could reduce about 25% salt content in the chicken nugget formulation with 20% white button mushroom as a meat extender.

Effects of long-term frozen storage on the quality and acceptance of gluten-free cassava pasta

Cold storage conditions during long-term periods can be critical for the quality of gluten-free products. The objective of this work was to elaborate gluten-free pasta using cassava starch and study the influence of different storage conditions on the textural and sensorial properties of gluten-pasta compared to regular pasta. Samples were initially frozen at two different temperatures, -50 °C and -150 °C, and then stored for six months at -25 °C. Physicochemical and rheological analyses were used to characterize the pasta dough. Then microbiological, instrumental texture, and sensorial analysis were used to further characterize the pasta throughout the cold storage period of 6 months. The gluten-free pasta's nutritional composition showed low fat and protein content and high crude fiber, carbohydrates, and energy value content in relation to the gluten-containing pasta. Both kinds of pasta dough presented a pseudoplastic behavior; however, the wheat flour pasta presented lower apparent viscosity. The texture profile of frozen pasta during the evaluation period did not significantly vary when comparing the two freezing temperatures. Although the firmness, chewability, and cohesiveness parameters slightly decreased during the storage, losses of firmness were not detected by the judges at the sensorial analysis. Finally, cassava starch pasta had a high acceptance. According to the purchase intention research, the judges routinely consume gluten-free pasta, showing the high commercialization potential of the obtained product.

Nutritional and Functional Properties of Gluten-Free Flours

This study characterized and compared 13 gluten-free (GF) flours (rice, brown rice, maize, oat, millet, teff, amaranth, buckwheat, quinoa, chickpea, gram, tiger nut, and plantain) for their nutritional and functional properties. For all GF flours investigated, starch was the major component, except for gram, chickpea, and tiger nut flours with lower starch content (<45%), but higher fiber content (8.8–35.4%). The higher amount of calcium, magnesium, zinc, potassium, phosphorus, similar values for iron and lower content of sodium in gram, makes this flour a good alternative to chickpea or other GF flour to develop healthier food products. Amaranth flour had a high protein digestibility, while tiger nut and millet flours were less digestible. Gram, chickpea, quinoa, buckwheat, and oat flours fulfilled amino acids recommendation for daily adult intake showing no limiting amino acid. Total polyphenolic content and antioxidant capacity showed higher values for buckwheat, followed by quinoa and maize flours. Gram, chickpea, maize, and quinoa flours are good candidates to improve health conditions due to lower saturated fatty acid content. The findings of this study provide useful insights into GF flours and may contribute to the development of novel gluten-free products like bread, cookies, or pasta.

Effects of thermal properties and behavior of wheat starch and gluten on their interaction: A review

Starch and gluten, the most important macromolecules in wheat flour, vary in thermal properties. The thermal behavior of starch, gluten and their complexes during the manufacture and quality control of flour products need to be accurately understood. However, the high complexity of starch-gluten systems impedes the accurate description of their interactions. When heated within varying temperature ranges and when water molecules are involved, the behaviors of amylose and amylopectin change, and the properties of the starch are modified. Moreover, important indicators of starch granules such as gelatinization temperature, peak viscosity, and so on, which are encapsulated by the gluten matrix, are altered. Meanwhile, the high-temperature environment induces the opening of the intrachain disulfide bonds of gliadin, leading to an increase in the probability of interchain disulfide bond formation in the gluten network system. These behaviors are notable and may provide insights into this complex interaction. In this review, the relationship between the thermal behavior of wheat starch and gluten and the quality of flour products is analyzed. Several methods used to investigate the thermal characteristics of wheat and its flour products are summarized, and some thermal interaction models of starch and gluten are proposed.

Berrios J. Tiger Nut (Cyperus esculentus) as a Functional Ingredient in Gluten-Free Extruded Snacks

Tiger nut (TN) is a nutritious source of gluten-free flour, used generally in healthy beverages, but its incorporation in gluten-free extruded snacks has not been explored. TN flour was blended at different concentrations (up to 70%) with rice flour and soluble fiber, for the development of gluten-free snacks on a twin-screw extruder. The effect of TN inclusion in the formulations was evaluated on relevant physiochemical characteristics of the snacks. Viscoamylograph of the raw formulations showed that TN addition increased (p < 0.01) onset temperature and delayed peak viscosity. In the extruded flours, TN contributed to limit the starch degradation during extrusion. Diameter, expansion ratio, true density, and total pore volume of the extrudates were reduced (pf < 0.01) by the increased TN content in the formulations, while bulk density rose. The surfaces of the extruded snacks were modified by the increasing inclusion of TN in substitution of rice in the formulations. Extrudates containing 10% TN showed the best overall texture profile. Moreover, TN addition enhanced the ash and protein content of the snacks and increased their total antioxidant activity. This study demonstrated that incorporation of 10% TN flour into rice-based formulation was suitable for making gluten-free snacks with acceptable physical properties.

Antistaling properties of encapsulated maltogenic amylase in gluten-free bread

Staling of bakery products especially gluten-free products is a challenge on the development of these products. For retarding staling of gluten-free bread, maltogenic amylase (MAase) at concentrations of 8.2, 45, and 82 mg/ml was encapsulated into beeswax (BW) at 1%, 2.5%, and 4% levels. Results showed the treatment with 8.2 mg/ml MAase and 2.5% beeswax had the highest encapsulation efficiency (42.04%) and chosen for subsequent experiments. The size of encapsulated particles was 362.70 nm and had a zeta potential of -15.35 mV. Surface morphology of encapsulated MAase was almost spherical with layered appearance. The free and encapsulated MAase with the activity of 5.2 µmol/min were used in gluten-free batter and breads, respectively. In the rheological tests, batters containing free and encapsulated MAase showed lower cross over point than control batter (without enzyme or wall material) (59 and 53 Hz, respectively). Encapsulated MAase contained bread had darker crust, whiter and softer crumb, and more aerated structure in comparison with free MAase loaded one. Both breads containing MAase as free or encapsulated had higher moisture content and water activity in crust and crumb than control bread. However, bread with free MAase had softer crumb after four days of storage, and bread with encapsulated MAase had higher sensorial acceptability than other breads after 2 and 4 days of storage.

Dietary Fiber from Chickpea (Cicer arietinum) and Soybean (Glycine max) Husk Byproducts as Baking Additives: Functional and Nutritional Properties

Dietary fiber extracted from soybean and chickpea husks was used in the formulation of white bread. Treatments at different concentrations of dietary fiber (DF): bread + 0.15%, 0.3%, 1.5%, 2% soybean dietary fiber (SDF); bread + 0.15%, 0.3%, 1.5%, 2% chickpea dietary fiber (CDF), and a control treatment (Bread 0% DF) were used initially. However, the treatments that showed the greatest improvement effects were: bread + 2% SDF and bread + 2% CDF. The functionality and the nutritional contribution in the treatments were evaluated during four days of storage. The weight loss on the third day of storage was 30% higher in the control treatment than the products with 2% SDF and 2% CDF, while for the evaluation of firmness, the control obtained a hardness of 86 N, and treatments with 2% SDF and 2% CDF 60 N and 45 N, respectively. The presence of phenolic compounds and their antioxidant activity was evident, mainly in the 2% SDF treatment, which had a total phenolic content of 1036, while in the Bread 0% DF it was 232 mgEAC/kg. The antioxidant activity for 2% SDF by DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (3-ethyl-benzothiazoline-6-sulfonic acid), and FRAP (ferric reducing antioxidant power) was 1096, 2567, and 1800 µmolTE/kg, respectively. Dietary fiber addition favored the reduction of weight loss and firmness of white bread during storage. In addition, color was not affected and the content calcium, phenolics, as well as antioxidant capacity were slightly improved.

High fibre tiger nut pasta and xanthan gum: cooking quality, microstructure, physico-chemical properties and consumer acceptance

The feasibility of replacing wheat semolina by tiger nut flour (20 and 40%) and xanthan gum (1%) in order to obtain high fibre dry pappardelle with fair techno-functional, structural and sensory attributes, was assessed. The cooking properties, texture, colour and sensory acceptance of uncooked and cooked pasta were evaluated. The proximate chemical composition of the raw materials, and the microstructure of the dry pasta were also assessed. The results in this manuscript address the improved nutritional value in terms of its dietary fibre, mineral content, oleic and linoleic acids, and the positive effects on the textural characteristics and cooking behaviour achieved on dry tiger nut based pappardelle using 1% of xanthan gum as a structural agent. Micrographs revealed in fact that the gluten network was better formed when xanthan gum was used. Furthermore, the obtained results seem to support that consumers would prefer pappardelle with 40% tiger nut flour.

Understanding gluten-free dough for reaching breads with physical quality and nutritional balance

In the last decade the development of gluten-free foodstuffs has attracted great attention as a result of better diagnoses of coeliac disease and a greater knowledge of the relationship between gluten-free products and health. The increasing interest has prompted extensive research into the development of gluten-free foodstuffs that resemble gluten-containing foods. This review aims to provide some insights on dough functionality and process conditions regarding bread quality and to point out recent research dealing with the nutritional composition of those products. Gluten-free dough results from the combination of different ingredients, additives, and the processing aids required for building up network structures responsible for bread quality. Some relationships between dough rheology and bread characteristics were established to identify possible predictor parameters. Regarding bread-making processes, the impact of mixing, dough treatment and baking is stated. Nutritional quality is an important asset when developing gluten-free breads, and different strategies for improving it are reviewed. Gluten-free bread quality is dependent on ingredients and additives combination, but also processing can provide a way to improve bread quality. Nutritive value of the gluten-free breads must be always in mind when setting up recipes, for obtaining nutritionally balanced bread with adequate glycaemic index.