Optimization of Gluten-Free Bread Formulation Using Whole Sorghum-Based Flour by Response Surface Methodology

Microwave-treated rice flour halves the need of hydroxypropyl methylcellulose in the formulation of gluten-free bread

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.

The study aimed to define the ideal proportions of pseudocereal flours (PF) in sensory-accepted gluten-free bread (GFB) formulations. The characteristics of GFB developed with PF (amaranth, buckwheat, and quinoa) were verified through a mixture design and response surface methodology. Three simplex-centroid designs were studied to analyze the effects of each PF and their interactions with potato starch (PS), and rice flour (RF) on GFB’s physical and sensory characteristics, each design producing three single, three binary and six ternary GFB formulations. Results showed that using PF alone resulted in unacceptable GFB. However, the interactions between PF and RF improved the loaf specific volume and the crumb softness and also enhanced appearance, color, odor, texture, flavor, and overall liking. Moreover, the composite formulations prepared with 50% PF and 50% RF (flour basis) presented physical properties and acceptability scores like those of white GFB, prepared with 100% RF or a 50% RF + 50% PS blend (flour basis). Maximum proportions of PF to obtain well-accepted GFB (scores ≥7 for all evaluated attributes on a 10-cm hybrid hedonic scale) were defined at 60% for amaranth flour (AF), 85% for buckwheat flour (BF), and 82% for quinoa flour (QF) in blends with RF.

Optimization of gluten-free bread production with low aflatoxin level based on quinoa flour containing xanthan gum and laccase enzyme

Effect of added psyllium and food enzymes on quality attributes and shelf life of chickpea-based gluten-free bread

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.

Grain and flour characterizations of two improved sorghum varieties (Gambella-1107 and 76T1#23) grown in Ethiopia was conducted from the perspective of their incorporation into Gluten-Free Bread (GFB). The sample varieties were evaluated for physicochemical and functional properties and their antinutrient compositions. In addition, GFB was produced from sorghum flour (50% flour weight basis), corn flour (20%), potato flour (10%) and chick pea flour (20%). Response Surface Methodology (RSM) was used to optimize the formulation and process conditions. The independent variables (factors) for the experiment were egg albumin level, milk powder level, baking temperature and time. The investigated responses were volume expansion, moisture loss, loaf height and bread hardness. Overall optimization, conducted by overlaying the 3-D plots under investigation, was able to identify an optimal range of the independent variables within which the four responses were simultaneously optimized. The point chosen as representative of this optimal area corresponded to egg albumin (2.5% flour-weight basis), milk powder (7.5%), temperature (220°C) and baking time (35 min), process conditions under which the model predicted volume expansion (597 cm3), moisture loss (4.02%), loaf height (3.43 cm) and bread hardness (3.88 N/g). The optimum GFB contain 78.9% dry matter, 12.3% crude protein, 3.9% crude fat, 2.4% crude fiber, 1.7% total ash and 58.6% total carbohydrates. Sensory evaluation indicated that the overall acceptability of the optimum GFB was much more similar to commercial GFB produced by local bakeries than the existing formulated GFB. Hence, the optimum formulation and process conditions can be used as starting point for bakers to produce GFB and to contribute to the eradication of the celiac problems in Ethiopia.

A sourdough process based on fermented chickpea extract as leavening and anti-staling agent for improving the quality of gluten-free breads

Bread is a cereal-based product, commonly from wheat flour and trough the process of mixing, fermentation, and baking steps until the changes in flavor, shape, and chemical composition occur. Wheat flour content gliadin and glutenin that form gluten which can cause an intestine inflammation in patients of celiac diseases. They should avoid to consume gluten so need gluten-free product such as gluten free bread. The Gluten-free bread made from rice flour, corn starch, and cassava starch with proportion of 74.2% cornstarch, 17.2% rice flour, and 8.6% cassava starch. In general gluten-free white bread has poor capability to retain gas from fermentation, so will has firm crumb, poor loaf and easy to be stahling. This condition can be improved by addition of hydrocolloid such as xanthan gum. Randomized Block Design (RBD) used in research. The treatment was concentration of xanthan gum 0.5%, 1%, 1.5%, 2%, and 2.5%. and repeated five times. Observation was done on water content, hardness, compressibility, specific volume, and preference tests for crumb pore, texture (mouthfeel), and moistness. The data were analyzed with Anova α = 5% and than continued with Duncan’s Multiple Range Test (DMRT) at α = 5% when the treatment gave significant influence. The best treatment is determined according to the Effectiveness Index. The result showed that the use of xanthan gum has no effect on the water content of bread, but influence the hardness, compressibility, specific volume, and sensory evaluation of gluten-free white bread made from cornstarch, rice flour, and cassava starch. The higher the concentration of xanthan gum results in higher value of hardness, compressibility, and specific volume of gluten-free bread. The treatment of 2% xanthan gum showed to give the best gluten free bread with 23.89% of water content, 23.8 N of hardness, 98.02% of compressibility, 2.1675 cm3/g of volume specific, and give the best score in preference test.

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 formulation for gluten free bread was optimized on the basis of specific volume, crumb firmness and overall acceptability of the bread. A rotatable central composite design (CCRD) was applied on three control variables viz. xanthan gum, extruded rice flour and corn starch varying within the range (-α to +α) of 0.5–1.5%, 15–35% and 15–35% w/w, respectively. All three responses were significantly (p&lt;0.05) affected by the combinations of independent variable. The quadratic polynomial models for the measured responses could be successfully used for their prediction during baking. The numerical optimization suggested a proportion (% w/w) of xanthan gum: rice flour: corn starch = 0.94:24.91:25.11 with high overall acceptability, comparable specific volume and crumb firmness values with respect to wheat bread. Shelf life analysis of the optimized formulation over six days revealed that, as crumb firmness increased, crust firmness and crumb moisture decreased. Keywords: Rice flour, Corn starch, Xanthan gum, Gluten free bread, Optimization, Response surface methodology

As a sustainable ingredient, acorn flour supports biodiversity and reduces dependence on conventional grains, promoting eco-friendly gluten-free (GF) food production. This study investigated the incorporation of increasing levels of Quercus robur acorn flour in GF bread formulation and evaluated its effect on the physico-chemical and nutritional attributes of the product. Water content for each bread formulation was empirically optimized to obtain the largest loaf expansion and softest crumb. Optimized acorn-enriched GF breads were characterized for specific volume, crumb hardness, moisture and total (poly)phenolic contents, antioxidant activity, and in vitro starch digestibility. From a technological perspective, acorn flour was successfully integrated into GF bread, with water content modulation playing a key role in optimizing bread volume and texture. The recommended substitution level was below 30% to maintain desirable texture and structural characteristics. From a nutritional standpoint, acorn flour incorporation significantly increased dietary fiber, resistant and slowly digestible starch contents, while antioxidant activity was significantly enhanced at acorn flour inclusion levels of 10% or higher. These findings corroborate Quercus robur acorn flour as a valuable ingredient for improving the nutritional profile of gluten-free bread.

Recently, there has been an increase in demand for gluten-free (GF) products due to the growing number of gluten-intolerant and healthy individuals choosing to follow a gluten-free diet. Gluten-free bread (GFB) is a staple food product; therefore, many recent studies have reported the nutritional properties of GFB. However, an overview of the current ingredients and nutritional labeling of GFB worldwide has not yet been provided. This review aimed to gather the latest information regarding the most used ingredients in GFB formulations and the nutritional quality of these products from different countries, based on studies published in the last decade (2010–2020). Our analysis showed that GFB had a lower protein and a higher fat content than gluten-containing bread, and the dietary fiber content was highly variable between countries. Some studies have revealed a high glycaemic index in most products, which is associated with the extensive use of rice flour and starch as the main ingredients in GFB formulation. Label information presented significant differences from the data obtained through the chemical analysis of fiber and other nutritional components. Micronutrient fortification is not common in the GFB. The nutritional quality of commercial GFB is a crucial issue that needs to be addressed.

Gluten free (GF) breads require a gluten replacement to provide structure and gas retaining properties in the dough and mimic the viscoelastic properties of gluten. Hydroxypropylmethylcellulose (HPMC), which forms thermoreversible gel networks on heating had proved the most effective in structuring baked products. Response surface methodology was used to optimize a GF bread formulation based on ingredients such as maize starch and rice flour, which are naturally GF. (HPMC) and water (W) were the predictor variables (factors) and loaf specific volume, crumb firmness, and overall acceptability were the dependent variables (responses) used to assess the product quality. The optimal formulation, determined from the data, contained 1.5 kg/100 kg HPMC and 88.7 kg/100 kg Water, corn starch-rice flour blend basis (sfb). The developed mathematical models for the measured responses could be successfully used for their prediction during baking. Shelf life study of the optimized formulation revealed that bread stored under modified atmosphere packaging (MAP) exhibited lower crumb firmness and moisture content values, thus remained softer through storage. Scanning electron microscopy of the crumb showed continuum matrix between starch and HPMC, in the optimized formulation, obtaining a more aerated structure.

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.