Effect of protease treatment on the baking quality of brown rice bread: From textural and rheological properties to biochemistry and microstructure

Mechanism of action of three different glycogen branching enzymes and their effect on bread quality

Bread staling adversely affects the quality of bread, but starch modification by enzymes can counteract this phenomenon. Glycogen branching enzymes (GBEs) used in this study were isolated from Deinococcus geothermalis (DgGBE), Escherichia coli (EcGBE), and Vibrio vulnificus (VvGBE). These enzymes were characterized and applied for starch dough modification to determine their role in improving bread quality. First, the branching patterns, activity on amylose and amylopectin, and thermostability of the GBEs were determined and compared. EcGBE and DgGBE exhibited better thermostable characteristics than VvGBE, and all GBEs exhibited preferential catalysis of amylopectin over amylose but different degrees. VvGBE and DgGBE produced a large number of short branches. Three GBEs degraded the starch granules and generated soluble polysaccharides. Moreover, the maltose was increased in the starch slurry but most significantly in the DgGBE treatment. Degradation of the starch granules by GBEs enhanced the maltose generation of internal amylases. When used in the bread-making process, DgGBE and VvGBE increased the dough and bread volume by 9 % and 17 %, respectively. The crumb firmness and retrogradation of the bread were decreased and delayed significantly more in the DgGBE bread. Consequently, this study can contribute to understanding the detailed roles of GBEs in the baking process.

Sorghum (Sorghum bicolor L. Moench) Gluten-Free Bread: The Effect of Milling Conditions on the Technological Properties and In Vitro Bioaccessibility of Polyphenols and Minerals

The absence of gluten proteins in sorghum allows for the production of baked goods that are suitable for celiacs. Previous studies have shown that the milling process affects the performance of sorghum flour in baked products, especially those that are gluten-free (GF). This study aimed to explore the effects of mill type (impact and roller) on flour properties and GF bread quality by assessing the technological quality, antioxidant activity, and mineral content of the bread. All particle populations of flour obtained via both millings presented a bimodal distribution, and the volume mean diameter (D 4,3) ranged from 431.6 µm to 561.6 µm. The partially refined milled flour obtained via polishing and impact milling produced bread with a soft crumb, fewer but larger alveoli in the crumb, and a structure that did not collapse during baking, showing the best performance in bread quality. In the in vitro bread digestibility assay, the total polyphenol content and antioxidant activity decreased during the digestion steps. High mineral (Cu, Fe, Mn, and Zn) contents were also found in a portion of the bread (120 g) made with whole sorghum flour; however, their potential bioavailability was reduced in the presence of a higher amount of bran.

Evaluation of producing gluten-free bread by utilizing amaranth and lipase and protease enzymes

Generating high pleasant and nutritious gluten-free (GF) bread for sufferers with celiac disease (CD) is a main task for food technologists. Amaranth is a useful nutrition and gliadin-free and could be utilized in GF products. At this study, by using different substitutions of amaranth flour (0%, 15%, 25%) GF bread samples were produced, and the effects of lipase and protease enzymes as bread improver have been investigated. On this assessment, physicochemical (ash, moisture, specific volume, bread yield, color index and porosity) and rheological (springiness, chewiness, cohesiveness, hardness and staling) characteristic, microstructure and sensory feature of bread were evaluated. The consequences tested the production bread with acceptable sensory properties is feasible with the aid of applying amaranth flour in GF bread formulations. Applying 15% amaranth flour increased meaningfully bread porosity and specific volume, but texture hardness was notably decreased. 25% amaranth flour formulation lowered hardness, specific volume and porosity of bread samples. Utilizing lipase and protease enzymes in 15% amaranth flour reduced texture hardness, porosity and specific volume, while the enzymes at 25% amaranth flour heightened the mentioned bread properties. In this result, for lower amaranth flour substitution (15%), using enzymes in formulation is not necessary, however enzymes in 25% Amaranth flour substitution could promote bread texture, porosity and specific volume.

Impact of Sunflower Meal Protein Isolate Supplementation on Pasta Quality

Globally, there is an increased demand for plant- and animal-derived proteins. However, animal-derived proteins are still expensive and expected to negatively impact the environment. Sunflower seeds, an excellent source of proteins, are one of the most critical oilseeds produced in the world markets. This study used sunflower meal protein isolate (SMPI), wheat flour (WF), and their blends to make pasta with good sensory features and higher nutritional value. The chemical and amino acid compositions, rheological properties, color attributes, cooking quality, sensory properties, and texture analysis of pasta were evaluated. SMPI showed a high protein content (87.12%) compared to WF (10.90%). The pasta was made from WF with supplementing SMPI at three concentrations (3.0, 6.0, and 9.0% w/w) to improve the nutritional quality. Farinograph parameters showed that water absorption, arrival time, dough development time, mixing tolerance index, dough weakening, and dough stability increased as the percentage of SMPI in the blends increased. The results also showed that the color (L*, a*, and b*) of pasta samples was darker as the mixing level of SMPI increased. The obtained sensorial results confirmed this result. The cooking quality of pasta revealed that the weight, volume, and cooking loss of prepared pasta with SMPI (3.0–9.0%) increased compared to the control sample (pasta with 100% WF). Moreover, sensory evaluation of pasta revealed that all samples were acceptable. Nonetheless, mouth feel and overall acceptability of pasta reinforced with 3.0 and 6.0% SMPI did not notably impact the pasta compared to the control sample, while flavor did not significantly influence the pasta with 3.0% SMPI. These findings demonstrated that pasta supplemented with SMPI could benefit the pasta industry, which requires a suitable technological process to obtain novel products.

Dry Heating of Cowpea Flour below Biopolymer Melting Temperatures Improves the Physical Properties of Bread Made from Climate-Resilient Crops

Improving the technological functionality of climate-resilient crops (CRCs) to promote their use in staple foods, such as bread, is relevant to addressing food and nutrition security in Africa. Dry heating of cowpea flour (CPF) was studied as a simple technology to modulate CPF physicochemical properties in relation to bread applications. For this purpose, the melting behavior of cowpea starch and proteins in CPF was first studied and modeled using Flory–Huggins theory for polymer melting. Next, dry-heating conditions were investigated based on the predicted biopolymer melting transitions in CPF to be well below starch and protein melting. The pasting properties (i.e., peak viscosity, final viscosity, breakdown and setback) of CPF could be selectively modulated depending on temperature-time combinations without altering the thermal behavior (i.e., melting enthalpies) of CPF. Water-binding capacity and soluble solids decreased with the increased severity of the temperature-time combinations. Dry-heated CPF added to CRC-based bread significantly improved crumb texture. In particular, dry heating at 100 °C for 2 h provided bread with the highest crumb softness, cohesiveness and resilience. The positive effects on the crumb texture could be largely related to enhanced starch integrity, as indicated by a reduction in breakdown viscosity after treatment. Overall, dry heating of CPF under defined conditions is a promising technology for promoting the use of CPF as a techno-functional and protein-rich ingredient in bread-type products.

Effective Use of Plant Proteins for the Development of "New" Foods

Diversity in our diet mirrors modern society. Affluent lifestyles and extended longevity have caused the prevalence of diabetes and sarcopenia, which has led to the increased demand of low-carb, high-protein foods. Expansion of the global population and Westernization of Asian diets have surged the number of meat eaters, which has eventually disrupted the supply–demand balance of meat. In contrast, some people do not eat meat for religious reasons or due to veganism. With these multiple circumstances, our society has begun to resort to obtaining protein from plant sources rather than animal origins. This “protein shift” urges food researchers to develop high-quality foods based on plant proteins. Meanwhile, patients with food allergies, especially gluten-related ones, are reported to be increasing. Additionally, growing popularity of the gluten-free diet demands development of foods without using ingredients of wheat origin. Besides, consumers prefer “clean-label” products in which products are expected to contain fewer artificial compounds. These diversified demands on foods have spurred the development of “new” foods in view of food-processing technologies as well as selection of the primary ingredients. In this short review, examples of foodstuffs that have achieved tremendous recent progress are introduced: effective use of plant protein realized low-carb, high protein, gluten-free bread/pasta. Basic manufacturing principles of plant-based vegan cheese have also been established. We will also discuss on the strategy of effective development of new foods in view of the better communication with consumers as well as efficient use of plant proteins.

A review on rice yellowing: Physicochemical properties, affecting factors, and mechanism

Yellowing is a critical issue that reduces quality and commodity value of rice. This article presents an overview on rice yellowing and the mechanism of rice yellowing was addressed as the emphasis. The change of physicochemical and nutritive properties in yellowed rice depends on the exposure temperature and time, as well as rice cultivar. The temperature and moisture on rice yellowing were dominant. There is no consensus on the relationship between microorganisms and rice yellowing. The occurrence of yellowing is mainly associated with heat stress induced by heaping heat or respiration of grain, and the yellowing is the collective result of primary and secondary metabolism. The upregulation of flavonoids is the direct cause of rice yellowing, which can be used as metabolic markers of rice yellowing. The Maillard reaction also contributes to yellowing during storage. Aeration and cooling are recommended to lessen the occurring of rice yellowing during commercial storage.

A review on mechanistic aspects of individual versus combined uses of enzymes as clean label-friendly dough conditioners in breads

Numerous dough improvers are used alone or in combination to enhance the quality of baked goods such as breads. While modern consumers demand consistent quality, the expectations for ingredients have changed over the past few years, and reformulations have taken place to provide "clean label" options. However, the effects and mechanisms of blended dough conditioners suitable for such baked products have not been systematically summarized. In this review, dough and bread properties as affected by different improver combinations are examined, with a focus on additive or synergistic interactions between enzymes or between enzymes and ascorbic acid. The combination of enzymes that hydrolyze starch and cell wall polysaccharides has been shown to reduce textural hardness in fresh and stored bakes goods such as breads. Enzymes that hydrolyze arabinoxylans, the main nonstarch polysaccharide in wheat, have synergistic effects with enzymes that result in cross-linking of wheat flour biopolymers. In some studies, the effects of bread improvers varied for wheat flours of different strength. Overall, bread products in which wheat is used in whole grain form or in a blend with other flours especially benefit from multiple improvers that target different flour constituents in doughs.

A Systematic Review of Gluten-Free Dough and Bread: Dough Rheology, Bread Characteristics, and Improvement Strategies

High-quality, gluten-free doughs and bakery products are clearly more difficult to produce than wheat flour-based products. The poor quality of the breads that are currently available demonstrates that manufacturing remains a significant technological problem. This is mainly due to the absence of gluten, which has a huge negative impact on dough rheology and bread characteristics. Gluten replacement is still the major challenge in the development of doughs and baked goods. The literature documents various improvement strategies. The most active approach seeks to identify alternative ingredients that can mimic the viscoelastic properties of the gluten network, notably hydrocolloids, enzymes, emulsifiers, and alternative sources of protein. However, other innovative strategies, such as high pressure, using heat to dry flour, and sourdough fermentation, have been investigated. In this context, the first aim of this review is to summarize current knowledge regarding gluten-free doughs, breads, and bakery products. Secondly, as it is clear that the manufacture of gluten-free products remains a key challenge, it suggests some improvement strategies that can boost their nutritional, technological, and sensorial characteristics.

The effect of Quinoa flour and enzymes on the quality of gluten-free bread

Gluten-free products usually are produced by refined flours such as rice and corn flour, which the bran is separated during processing. These flours are not nutritionally as rich as gluten containing products. Moreover, gluten-free bread has several technical problems such as unfavorable texture, low volume, quick staling, and weaker color and taste compared with the wheat flour products. In this research, gluten-free bread with various substitution of quinoa (0%, 15%, and 25%) was produced and the effects of lipase and protease enzymes on the quality of bread were investigated. The gluten-free bread properties like physicochemical properties, rheological properties, and bread microstructure were evaluated. Moreover, the sensorial properties were assessed. The results have demonstrated that gluten-free bread with quinoa flour has favorable properties. Also, lipase and protease enzymes could improve the quality of the bread containing quinoa. Protease and lipase enzymes increased the bread volume, specifically in sample containing 15% quinoa substitution. Moreover, the staling was delayed in sample 25% quinoa substitution. The bread was accepted by consumers, and the highest score belonged to 25% substitution of quinoa flour.

Effects of different carbohydrases on the physicochemical properties of rice flour, and the quality characteristics of fermented rice cake

The rice flours were hydrolyzed using α-amylase (A), α-amylase and xylanase (AX), and α-amylase, xylanase and β-amylase (AXB). The effects of different enzymatic rice flour hydrolysates (ERH) on the quality of the fermented rice cake (FRC) were determined at 25 °C for 4 days. ERH had higher porosity, water absorption index, water solubility index and lower viscosity than the control. Moisture content of FRC center decreased significantly after 4 days. Specific volumes of fresh A-, AX- and AXB-FRC were higher than the control. Color of fresh A-FRC was closer to that of the control. AXB-FRC had lower hardness and firming rate than other samples during storage. After 4 days of storage, FRC with ERH had lower endotherm enthalpy and more uniform and clearer pore structure than the control. Therefore, the ERH with single or mixed enzymes could improve the structure of FRC, and extend its shelf-life.

Gluten-free breadmaking affected by the particle size and chemical composition of quinoa and buckwheat flour fractions

This study aimed at assessing the effect of physicochemical properties and the particle size of different fractions of buckwheat and quinoa on the behaviour of gluten-free dough and bread quality. Quinoa and buckwheat grains were milled with a hammer mill and then separated in three fractions. These fractions where then re-milled with a cyclonic mill to obtain samples of similar sizes. Results showed that the chemical composition of these fractions was very different and played a major role on bread quality. Proteins, lipids and fibre negatively affected bread quality, whereas starch-rich fractions were more adequate for breadmaking. Re-milling quinoa and buckwheat fractions increased bread volume, although chemical composition still influenced bread properties. For hammer-milled fractions, both the finest fractions resulted in breads with higher technological quality, as well as a final product with more fibre, minerals and proteins.

Gluten-Free Rice Breading Using Composited Rice Flour and Pre-Germinated Brown Rice Flour for Health Benefits

Gluten-free rice breading (RB) is generally prepared by shredding of gluten-free rice bread. It is an alternative product for Celiac patients, who are gluten allergic. The aim of this research was to formulate gluten-free rice bread formula by using composited rice flour (RF) and pre-germinated brown rice flour (PGBRF) from two Thai rice cultivars, Pathum-Thani1 (15% amylose) and Phitsanulok2 (27% amylose) at the ratio of 1:1, by considering the structural properties of bread, health benefit of breading, and the properties of breading as coating material of fried frozen croquette (C-) and compared to those of samples prepared from wheat flour. Increasing PGBRF from 0% to 50% in gluten-free rice bread formula increased the puffed cell wall of air cell in gluten-free rice bread. Antioxidative activity of RB containing 50% PGBRF (RB-50%) was 4 and 9 times higher than RB without PGBRF (RB-0%) and wheat breading (WB), respectively. WB contained 356,289 mg/kg of gluten, while RB contained less than 2 mg/kg of gluten, which could be labeled "gluten-free". When compared all breading samples as coating material of C-, oil absorption of C-RB-50% (14.32%) was 3 times lower than that of WB (44.36%). Therefore, the RB-50% had health benefits for consumers who are suffered from Celiac disease and also other health-conscious consumers considering the higher antioxidative properties and lower oil uptake than the consumption of WB.

Recent practical researches in the development of gluten-free breads

Wheat bread is consumed globally and has played a critical role in the story of civilization since the development of agriculture. While the aroma and flavor of this staple food continue to delight and satisfy most people, some individuals have a specific allergy to wheat or a genetic disposition to celiac disease. To improve the quality of life of these patients from a dietary standpoint, food-processing researchers have been seeking to develop high-quality gluten-free bread. As the quality of wheat breads depends largely on the viscoelastic properties of gluten, various ingredients have been employed to simulate its effects, such as hydrocolloids, transglutaminase, and proteases. Recent attempts have included the use of redox regulation as well as particle-stabilized foam. In this short review, we introduce the ongoing advancements in the development of gluten-free bread, by our laboratory as well as others, focusing mainly on rice-based breads. The social and scientific contexts of these efforts are also mentioned.

A systematic reconsideration on proteases

Proteases are a group of large complex enzyme molecules that perform highly focused proteolysis functions. A vast quantity of the protease enzymes is predominantly sourced from microbial fermentation process, although proteases tend to natively present in plant, animals and humans. Proteases possess a pervasive importance in medical and pharmaceutical sector, because of its enriched specificity towards biomolecules. They are also actively encompassed in regulating certain physiological pathways. A distinct territory of human disorders is treated by substrate specific proteases. Enormous numbers of catalytic activities in habitual metabolism process of a living organism are protease dependent. Pilot scale researches and product development in industrial biotechnology sectors are wholly based on any one of the protease enzymes. The applications of the protease enzymes and its economic benefits of being an eco-friendly material are far-reaching. This review presents a brief overview on the classification and sources of various types of proteases. We describe the essential evidences of role of protease in different sectors. The proteases could be a potential relieves to harmful synthetic chemicals in distinctive industrial processes and thus gains global perception.

Innovative processing techniques for altering the physicochemical properties of wholegrain brown rice (Oryza sativa L.) - opportunities for enhancing food quality and health attributes

Rice is a globally important staple consumed by billions of people, and recently there has been considerable interest in promoting the consumption of wholegrain brown rice (WBR) due to its obvious advantages over polished rice in metabolically protective activities. This work highlights the effects of innovative processing technologies on the quality and functional properties of WBR in comparison with traditional approaches; and it is aimed at establishing a quantitative and/or qualitative link between physicochemical changes and high-efficient processing methods. Compared with thermal treatments, applications of innovative nonthermal techniques, such as high hydrostatic pressure (HHP), pulsed electric fields (PEF), ultrasound and cold plasma, are not limited to modifying physicochemical properties of WBR grains, since improvements in nutritional and functional components as well as a reduction in anti-nutritional factors can also be achieved through inducing related biochemical transformation. Much information about processing methods and parameters which influence WBR quality changes has been obtained, but simultaneously achieving the product stabilization and functionality of processed WBR grains requires a comprehensive evaluation of all the quality changes induced by different processing procedures as well as quantitative insights into the relationship between the changes and processing variables.

Dynamic viscoelasticity of protease-treated rice batters for gluten-free rice bread making

Papain (cysteine protease), subtilisin (Protin SD-AY10, serine protease), and bacillolysin (Protin SD-NY10, metallo protease) increased the specific volume of gluten-free rice breads by 19-63% compared to untreated bread. In contrast, Newlase F (aspartyl protease) did not expand the volume of the rice bread. In a rheological analysis, the viscoelastic properties of the gluten-free rice batters also depended on the protease categories. Principal component analysis (PCA) analysis suggested that the storage and loss moduli (G' and G″, respectively) at 35 °C, and the maximum values of G' and G″, were important factors in the volume expansion. Judging from the PCA of the viscoelastic parameters of the rice batters, papain and Protin SD-AY10 improved the viscoelasticity for gluten-free rice bread making, and Protin SD-NY effectively expanded the gluten-free rice bread. The rheological properties differed between Protin SD-NY and the other protease treatments.

How to improve the gluten-free diet: The state of the art from a food science perspective

The celiac disease is the most common food intolerance and its prevalence is increasing. Consequently, use of gluten-free diet has expanded, notwithstanding consumption as therapy for other gluten-related disorders or by wellbeing people without any medical prescription. Even the therapeutic efficiency has undoubtedly proven, several drawbacks mainly regarding the compliance, nutritional deficits and related diseases, and the alteration of the intestinal microbiota have described in the literature. Food science has been considered as one of the primary area of intervention to limit or eliminate such drawbacks. Efforts have approached shelf life, rheology and palatability aspects but more recently have mainly focused to improve the nutritional features of the gluten-free diet, and to propose dietary alternatives. The sourdough fermentation has shown the most promising results, also including a biotechnology strategy that has allowed the complete degradation of gluten prior to consumption.

Partial Characterization of the Proteolytic Properties of an Enzymatic Extract From "Aguama" Bromelia pinguin L. Fruit Grown in Mexico

Plant proteases are capable of performing several functions in biological systems, and their use is attractive for biotechnological process due to their interesting catalytic properties. Bromelia pinguin (aguama) is a wild abundant natural resource in several regions of Central America and the Caribbean Islands but is underutilized. Their fruits are rich in proteases with properties that are still unknown, but they represent an attractive source of enzymes for biotechnological applications. Thus, the proteolytic activity in enzymatic crude extracts (CEs) from wild B. pinguin fruits was partially characterized. Enzymes in CEs showed high proteolytic activity at acid (pH 2.0-4.0) and neutral alkaline (pH 7.0-9.0) conditions, indicating that different types of active proteases are present. Proteolytic activity inhibition by the use of specific protease inhibitors indicated that aspartic, cysteine, and serine proteases are the main types of proteases present in CEs. Activity at pH 3.0 was stable in a broad range of temperatures (25-50 °C) and retained its activity in the presence of surfactants (SDS, Tween-80), reducing agents (DTT, 2-mercapoethanol), and organic solvents (methanol, ethanol, acetone, 2-propanol), which suggests that B. pinguin proteases are potential candidates for their application in brewing, detergent, and pharmaceutical industries.

Effect of gluten, egg and soy proteins on the rheological and thermo-mechanical properties of wholegrain rice flour

The effect of protein addition on the rheological, thermo-mechanical and baking properties of wholegrain rice flour was investigated. Gluten, powdered eggs and soy protein concentrate were first analyzed in terms of rheological properties, alone and in admixture with rice flour. The temperature ramp tests showed clear differences in the rheological behavior of the batters supplemented with different proteins. The highest thermal stability was observed in case of soy protein samples. Frequency sweep tests indicated significant improvements of the rheological properties of rice flour supplemented with 15% gluten or soy proteins. The thermo-mechanical tests showed that, due to the high fat contents and low level of free water, the dough samples containing powdered eggs exhibited the highest stability. Addition of gluten resulted in a significant decrease of the dough development time, whereas samples with powdered eggs and soy proteins were more difficult to hydrate. The incorporation of proteins into the rice flour-based dough formulations significantly affected starch behavior by decreasing the peak consistency values. Concerning the quality of the rice flour-based breads, soy protein addition resulted in lighter crumb color and increased texture attributes, samples with gluten had better resilience and adhesiveness, whereas breads with egg protein were less brittle.

Influence of germination time of brown rice in relation to flour and gluten free bread quality

The effect of germination time on physicochemical characteristics of brown rice flour and its effect on gluten free bread qualities have been investigated. Germination was carried out at 28 °C and 100 % RH for 12, 24 and 48 h; brown rice and soaked brown rice was also analyzed. Significant changes on hydration and pasting properties of brown rice flour were found during germination. The starch degradation by enzyme activity could be evidenced with the decrease in viscosity and water binding capacity (WBC). No significant effect in specific volume, humidity and water activity of the gluten free bread was found as germination time increase, but a significant softness of the crumb was obtained. However, at 48 h of germination, the intense action of α amylase could result in excessive liquefaction and dextrinisation, causing inferior bread quality. Overall, germinated rice flour showed appropriate functionality for being used as raw ingredient in gluten free breadmaking.

Transamidation of gluten proteins during the bread-making process of wheat flour to produce breads with less immunoreactive gluten

Due to an increasing incidence of celiac disease (CD) and other gluten-related disorders, different gluten-free breads have been developed using starches and additives as a substitute for gluten. Thus, patients miss not only the taste and aroma of wheat bread but also risk their sensitive intestines. Therefore, modifying gluten to avoid an immune response in CD and its application to baking is in progress. The aim of the study was to enzymatically modify gluten on wheat flour, during bread-making avoiding the use of additives, to reduce immunoreactivity, preserving its properties. Microbial transglutaminase (mTG) or chymotrypsin (ChT) was used to bind lysine or valine to gluten proteins in a model system. The best conditions were directly applied to wheat flour for bread-making with and without punching at 45 min. Subsequently, the rheological properties of the doughs, specific volume of the loaves, immunoreactive gluten content and modification of the extracted proteins were evaluated. ChT-treated breads presented a better appearance with a more homogeneous crumb, higher specific volume values (3.34-4.25 cm(3) g(-1)) and higher reactive gluten reduction (up to 71%) than the mTG-treated ones (1.23-2.66 cm(3) g(-1)) with only a 42% reactive gluten reduction. Thus, transpeptidation during bread-making is a promising technology, although it is necessary to improve the modification process to obtain the reactive gluten reduction required in breads for the treatment of CD patients and other gluten-related disorders.

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.