The effects of emulsifiers on quality and staling characteristics of gluten‐free bread containing fermented buckwheat, quinoa, and amaranth

The influence of fermented buckwheat, quinoa and amaranth flour on gluten-free bread quality

The diet based on gluten free products is characterised by a low content of some nutritional components such as proteins and mineral components, as well as non-nutritional but physiologically important components like dietary fibre. Buckwheat grains are a rich source of proteins, which have a high biological value due to the well-balanced amino-acids composition, although its digestibility is relatively low. The aim of the present research was to investigate the influence of buckwheat flour addition on gluten free bread quality and their antioxidant capacity. In this study, own gluten free bread formula, composed of corn starch, potato starch, salt, yeast, pectin, sugar and sunflower oil was investigated. The buckwheat flour substituted corn starch at final amount of 10, 20, 30, 40% w/w of total ingredients in gluten free bread formula. The breads were baked in electric oven at 200°C for 25 min. The bread samples were freeze-dried, ground and sieved. The sensory quality of buckwheat enhanced gluten free breads was analysed using sensory profiling (QDA) and hedonic tests. The measurement of macroelements content in the crumb was carried out using the atomic absorption spectroscopy (AAS) method (SORAL-SMIETANA et al. 2001). The antioxidant capacity (AC) of the breads was evaluated by cyclic voltammetry (CV) method and free radical scavenging activities of 67% methanol extracts against 2,2-diphenyl-1-picryhydrazyl radical (DPPH.) as DPPH Radical Scavenging Activity (DPPH RSA). All breads were analysed for their total phenolics content. The buckwheat enhancing gluten free breads were in accordance to the requirements of Polish Standards (PN-A-74123) for gluten-free bread. The sensory profiles of gluten-free breads were dependant on the amount of buckwheat flour added. The overall quality of breads was the highest for bread with 40% buckwheat flour addition. The positive correlation between macroelements content and increasing amount of buckwheat flour was observed in breads. The antioxidant capacity of buckwheat enhanced gluten free breads determined by CV and DPPH RSA was related to the amount of added buckwheat flour. The total phenolics content was positively correlated with antioxidant capacity of the breads. In summary, buckwheat flour as a natural source of minerals and antioxidant activity, and also as a structure-forming factor improving the sensory quality, can be used for preparation of new buckwheat enhanced gluten free breads.

As prevalence of celiac disease increases, the demand for gluten-free products also increases. Researchers are still trying to improve gluten-free bread quality and shelf life to reach the quality of wheat bread. In this study, the aim was to obtain gluten-free breads made from frozen dough with acceptable specific volume, crumb firmness, and color and to investigate the effects of gum type and flaxseed concentration on the quality of gluten-free breads. Three different gum types (guar gum, xanthan gum, locust bean gum) were used. Gums were added to the formulation at 1 % level. Flaxseed was also added to the formulation at different concentrations (0, 2.5, and 5 %). After frozen storage at −20 °C for 10 days, frozen samples were thawed at +4 °C. Thawed samples were then fermented and baked in infrared-microwave (IR-MW) combination oven. The quality parameters (weight loss, specific volume, hardness, and color) of gluten-free breads were determined. In addition to the measurement of hardness of fresh samples, hardness of staled samples during the 72-h storage was also determined to investigate the effects of different formulations in retarding the staling of gluten-free breads. When the effects of gums and flaxseed concentration on the quality of breads were considered, the quality of gluten-free breads formulated with guar gum-5 % flaxseed was found to be better (with lower hardness, higher specific volume, and better color) than the other samples. The results obtained during the 72-h storage also demonstrated that gluten-free breads formulated with guar gum-5 % flaxseed had the lowest hardness values.

The buckwheat flour was studied as a potential healthy ingredient for improving the nutritional and technological quality of gluten-free bread. The effect of exchange of gluten-free formulation mass by buckwheat flour in 10, 20, 30 and 40 % was investigated. The increase in loaf specific volume with rising buckwheat flour addition was observed. Compared with the control sample, decrease in whiteness and increase in redness and yellowness of crumb were noticed. The rising amount of buckwheat flour in gluten-free bread formulation caused a decrease in crumb hardness during storage. This was in agreement with the decrease in starch gelatinisation enthalpy with the increasing amount of buckwheat flour in gluten-free formula in comparison with the control sample. Buckwheat flour could be incorporated into gluten-free formula and have a positive influence on bread texture and delaying its staling.

Besides an appealing texture and taste, gluten-free products should feature a well-balanced nutrient profile, since celiac disease or chronic inflammations are likely to induce malnutrition for involved patients. Due to their composition, pseudocereals represent a promising ingredient to improve nutrient profile of gluten-free bread. The objective of this study was to investigate the impact of quinoa bran on gluten-free bread quality, focusing on volume, pore size and sensory acceptance. The impact of quinoa bran was studied in a gluten-free bread formulation. Five different quinoa bran and two whole grain flour concentrations were evaluated and compared to a control formulation based on rice and corn flour. The rheological properties of quinoa bran as well as the effect on dough development up to a replacement level of 80 % were investigated. Baking tests were carried out, and loaf volume, crumb firmness and sensory characteristics were determined. Quinoa fractions significantly increased carbon dioxide formation (p < 0.05) due to a higher substrate availability. Gas retention was reduced by increasing bran levels (p < 0.05). Oscillation measurements indicated a firming impact of quinoa bran which might have caused a more permeable dough structure, promoting the release of carbon dioxide. With regard to the specific loaf volume significant differences were found across the quinoa milling fractions and the applied levels (p < 0.05). Overall this study demonstrated that 10 % bran improved the bread volume by 7.4 % and enhanced the appearance without compromising the taste.

Modified Sweet Potato Flour has been done by oxidation using H2O2 and irradiation. This flour was used to develop gluten free bread with addition Nuts (soy, mung bean, and red bean kidney) flour. The aim of this research was to determine the physicochemical, baking quality, and sensory evaluation of gluten free bread. Gluten Free Bread sample was compare with wheat flour and native sweet potato flour for the physicochemical (texture, color properties, proximate, and dietary fiber) and baking quality. The sensory evaluation was obtained only for the gluten free bread from modified sweet potato flour. Result showed that chemical properties bread made from modified sweet potato has higher moisture content, dietary fiber, moderate ash, and lower protein than wheat and native flour bread. The physic properties showed that the free gluten bread has higher hardness, springiness than wheat flour bread. The L color score of bread based modified sweet potato was not significantly different compare with wheat flour. Baking quality of the gluten free bread was lower than wheat flour. Sensory evaluation for the bread based on modified sweet potato with addition soybean flour showed the highest score for taste, aroma, color, and overall acceptance.

In this study, response surface methodology based on simplex- centroid design was used to optimize the gluten-free bread formulation with rice flour and cassava starch as independent variables. Bread formulations were evaluated by physicochemical analysis and descriptive sensory analysis encompassing appearance, structure, texture, and aroma parameters by a trained sensory panel. The five formulations composition showed statistical differences concerning aw, lipid and protein content. Carbohydrate was significantly correlated with specific volume and lipids with protein. Overall, rice flour's addition improved lipid and protein, whereas further rises in cassava starch allowed developing bread with higher specific volume and sensory scores. The optimum combinations of the variables to maximize scores of porosity, texture, elasticity, and protein content, should be obtained with 51.75% of rice flour and 48.25% of cassava starch. The use of the simplex-centroid design and the response desirability function in the optimization was useful for evaluating the influence and potential of the binary mixture of rice flour and cassava starch on the sensory quality and chemical characteristics of gluten-free bread. These research findings open the scope for further investigation of rice flour and cassava starch and their useful application in gluten-free bread processing.

Nutritional therapy – Facing the gap between coeliac disease and gluten-free food

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.

Effect of arabinoxylans and laccase on batter rheology and quality of yeast-leavened gluten-free breads

Psyllium husk powder was investigated for its ability to improve the quality and shelf life of gluten-free bread. Gluten-free bread formulations containing 2.86%, 7.14%, and 17.14% psyllium by flour weight basis were compared to the control gluten-free bread and wheat bread in terms of performance. The effect of time on crumb moisture and firmness, microbial safety, and sensory acceptability using a 10-cm scale was assessed at 0, 24, 48, and 72 h postproduction. Crumb firming was observed during the storage time, especially for the control gluten-free bread, which had a crumb firmness 8-fold higher than that of the wheat bread. Psyllium addition decreased the crumb firmness values by 65–75% compared to those of the control gluten-free bread during 72 h of storage. The longest delay in bread staling was observed with a 17.14% psyllium addition. The psyllium-enriched gluten-free bread was well accepted during 72 h of storage, and the acceptability scores for aroma, texture, and flavor ranged from 6.8 to 8.3, which resembled those of wheat bread. The results showed that the addition of 17.14% psyllium to the formulation improved the structure, appearance, texture, and acceptability of gluten-free bread and delayed bread staling, resembling physical and sensory properties of wheat bread samples during 72 h of storage. Therefore, according to the obtained results, this approach seems to be promising to overcome some of the limitations of gluten-free breadmaking.

The objective is to verify if gluten-free (GF) and gluten-containing (G) breads differ in their sodium content and lipid profile. Samples of GF (n = 20) and G (n = 14) sliced white sandwich bread of commercial brands most frequently consumed in Spain were collected. The fatty acid (FA) composition and the contents of sodium, fat, cholesterol and phytosterols were determined. Sodium, fat and cholesterol contents were significantly higher in GF bread. The FA composition also differed, while G breads declared in most instances the use of sunflower oil as fat ingredient and presented a higher polyunsaturated FA percentage; GF breads declared a wide variety of fats and oils as ingredients (coconut, palm, olive, sunflower, etc.) which was reflected in their FA profile. Cholesterol content was higher in GF bread because five samples declared the use of whole egg, while G samples did not include any egg product in their formulas. Phytosterol content was higher in G bread but its variability was greater in GF bread. In conclusion, nutritional quality of GF bread varied depending on the ingredients used and might be lower than that of G bread. However, these differences in composition could be reduced or eliminated through changes in the formulation of GF bread. Moreover, the comparison of the results obtained in our laboratory for fat and salt content with the declared contents on the labels showed a much higher deviation for GF samples and it can be concluded that the quality of the nutritional information declared was lower in GF samples.

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.

Jerusalem artichoke, a plant that can be grown in areas with limited irrigable land, contains valuable macro and micro nutrients. Nowadays, there is an increased demand for gluten-free products. In this study, the physical, chemical, microbiological, and sensory effects of adding Jerusalem artichoke to gluten-free bread production were investigated. As a result of the study, it was determined that as the amount of Jerusalem artichoke powder increased in the gluten-free bread formulation, the specific volume, baking loss, moisture, and pH of the bread decreased, while the amounts of fiber and ash increased. Additionally, the selenium, calcium, and magnesium contents in the bread also increased significantly (P &amp;lt;0.05). According to sensory evaluation results, gluten-free bread with 10% Jerusalem artichoke addition received the highest score in overall appreciation. The addition of Jerusalem artichoke powder to gluten-free bread dough improved the crumb and external appearance of the bread and eliminated some quality defects.

The effect of cassava-banana flour formulation and soy protein isolate (SPI) addition on gluten-free bread quality and antioxidant properties has been studied. The gluten-free flour composition was 25:75, 50:50, and 75:25 for cassava & banana flour with SPI levels ranged 0, 2.5, 5.0, and 7.5%. Wheat bread was used as control. Different gluten-free flour formulations and SPI addition affected the quality of gluten-free bread (height, specific volume, hardness, springiness, cohesiveness, and resilience) significantly. Banana flour gave a better specific volume compared to cassava flour, and the addition of SPI also increased the height and specific volume of gluten-free bread. Total phenolic content (TPC) and antioxidant activities (2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS)) of gluten-free bread were altered by the type of flour composition and SPI addition. Banana flour composition increased TPC & antioxidant capacities. The SPI inclusion on the gluten-free bread also increased TPC and antioxidant activities. The highest DPPH and ABTS content were achieved from 25:75 cassava: banana flour with 5% and 0 % SPI addition (3.25 and 3.16 μmol Trolox equivalent (TE) respectively). These values were higher than the wheat bread control (2.04, and 2.92 μmol TE/100 g, respectively). It can be inferred that banana flour and SPI inclusion in the gluten-free bread gave a better gluten-free bread quality and enhanced antioxidant capacities.