Quality and antioxidant property of buckwheat enhanced wheat bread

Common buckwheat (Fagopyrium esculentum Moench) was used to substitute 15% of wheat flour to make buckwheat enhanced wheat breads. Proximate composition, physical quality, functional components and antioxidant properties of buckwheat enhanced wheat breads were analysed and compared with those of white bread. Specific volumes of three breads were 6.10–6.75 cm³/g. Buckwheat enhanced wheat bread showed lower lightness and whiteness index values and higher redness and yellowness values. On a seven-point hedonic scale, all sensory results were 5.33–5.91, indicating that three breads were moderately acceptable. No differences were found in appearance, colour and overall sensory attributes for three breads, whereas both buckwheat enhanced wheat breads were rated higher in flavour and mouth feel. Buckwheat enhanced wheat bread contained more rutin and quercetin as expected. Buckwheat enhanced wheat bread was good in antioxidant activity, reducing power and 1,1-diphenyl-2-picrylhydrazyl radical scavenging ability with unhusked buckwheat enhanced wheat bread being the most effective. Overall, buckwheat enhanced wheat bread could be developed as a food with more effective antioxidant properties.     

Use of sourdough fermented wheat germ for enhancing the nutritional, texture and sensory characteristics of the white bread

Lactobacillus plantarum LB1 and Lactobacillus rossiae LB5, isolated from wheat germ and selected based on the kinetics of acidification, were used as starters for the manufacture of sourdough fermented wheat germ. A bread containing sourdough fermented wheat germ as an ingredient (SFWGB) was compared to breads made with (raw wheat germ bread, RWGB) or without (wheat flour bread, WFB) raw wheat germ. The higher concentration of free amino acids mainly differentiated SFWGB from WFB and RWGB. The in vitro protein digestibility of WFB was the highest, even if sourdough fermentation of wheat germ attenuated the difference. Phytase and antioxidant activities of SFWGB were highest. The specific volume and cell-total areas were also the highest for SFWGB. As determined by texture profile analysis, the values of hardness, resilience and fracturability of breads containing wheat germ were lower than those found in WFB. The crust lightness showed a decrease from WFB to SFWGB. As determined by sensory analysis, SFWGB had mainly acid taste and flavour and resulted more salty. Sourdough fermented wheat germ is an ingredient able to enhance nutritional, texture and sensory properties of bread.     

Evaluation of the effects of fat replacers on the quality of wheat bread

The performance of different fat replacers at various levels (Inulin powder, Inulin gel and Simplesse) in wheat bread and dough compared to a control containing block fat was examined. Empirical and fundamental rheological tests were carried out on the doughs. Volume yield, crumb texture, crust colour and crumb image characteristics were measured for the baked loaves. The addition of inulin gel was found to increase water absorption. Dough complex modulus for doughs containing fat was significantly lower (P<0.01) than the doughs containing the replacers. The addition of simplesse and inulin increased the complex modulus (P<0.01). Loaves containing the control fat and inulin gel had similar volume yields, significantly higher (P<0.01) than loaves containing simplesse or inulin powder. Inulin powder and simplesse had adverse effects on crumb hardness, producing slices significantly harder (P<0.01) than slices with the control fat or inulin gel. Overall it was found that breads containing the inulin gel were similar in quality characteristics to the control breads containing fat.     

Quality and antioxidant properties of bread containing turmeric (Curcuma longa L.) cultivated in South Korea

Turmeric (Curcuma longa L.) powder was used to substitute 0%, 2%, 4%, 6% and 8% of wheat flour for making turmeric wheat breads. Proximate composition, physical quality, functional components (curcumin and total phenols) and antioxidant properties of breads containing turmeric were analysed and compared with those of wheat bread. Hardness, crumb colour a and b values, curcumin content and total phenolic contents of breads significantly increased with the addition of turmeric powder. Water activity, specific volume and crumb colour L value of breads decreased with the addition of turmeric powder. Breads containing turmeric powder also showed good antioxidant activity as tested by the β-carotene-linoleate bleaching assay. A 4% substitution of wheat flour with turmeric powder showed acceptable sensory scores which were comparable to wheat bread. Breads containing turmeric powder can thus be developed as a health-promoting functional food.     

Optimization of ingredients and baking process for improved wholemeal oat bread quality

Baking technology for tasty bread with high wholemeal oat content and good texture was developed. Bread was baked with a straight baking process using whole grain oat (51/100 g flour) and white wheat (49/100 g four). The effects of gluten and water content, dough mixing time, proofing temperature and time, and baking conditions on bread quality were investigated using response surface methodology with a central composite design. Response variables measured were specific volume, instrumental crumb hardness, and sensory texture, mouthfeel, and flavour. The concentration and molecular weight distribution of β-glucan were analysed both from the flours and the bread. Light microscopy was used to locate β-glucan in the bread. Proofing conditions, gluten, and water content had a major effect on specific volume and hardness of the oat bread. The sensory crumb properties were mainly affected by ingredients, whereas processing conditions exhibited their main effects on crust properties and richness of the crumb flavour. β-glucan content of oat bread was 1.3/100 g bread. The proportion of the highest molecular weight fraction of β-glucan was decreased as compared with the original β-glucan content of oat/wheat flour. A great part of β-glucan in bread was located in the large bran pieces.     

Evaluation of viscoelastic properties and air-bubble structure of bread containing gelatinized rice

The impact of addition of gelatinized rice porridge to bread has been investigated on loaf volume, viscoelastic properties and air-bubble structure. We prepared four variety of bread: bread containing rice porridge (rice porridge bread), bread containing gelatinized rice flour (gelatinized rice flour bread), and wheat flour and rice flour breads for references. Instrumental analyses the bread samples were carried out by volume measurement of loaf samples, creep test and digital image analysis of crumb samples. Rice porridge bread showed the maximum specific volume of 4.51 cm³/g, and even gelatinized rice flour bread showed 4.30 cm³/g, which was larger than the reference bread samples (wheat and rice flour breads). The values of viscoelastic moduli of gelatinized rice flour bread and rice porridge bread were significantly smaller (p < 0.05) than those of wheat flour and rice flour breads, which indicates addition of gelatinized rice flour or rice porridge to bread dough encouraged breads softer. Bubble parameters such as mean air- bubble area, number of air-bubble, air-bubble area ratio (ratio of bubble area to whole area) were not significantly different among the bread crumb samples. Therefore, the bubble structures of the bread samples seemed to similar, which implied that difference of viscoelasticity was attributed to air-bubble wall (solid phase of bread crumb) rather than air-bubble. This study showed that addition of gelatinized rice to bread dough makes the bread with larger loaf volume and soft texture without additional agents such as gluten.     

Baking properties and microstructure of pseudocereal flours in gluten-free bread formulations

In the present study, the baking properties of the pseudocereals amaranth, quinoa and buckwheat as potential healthy and high-quality ingredients in gluten-free breads were investigated. Scanning electron micrographs were taken of each of the flours. The pasting properties of these flours were assessed using a rapid visco analyser. Standard baking tests and texture profile analysis were performed on the gluten-free control and pseudocereal-containing gluten-free breads. Confocal laser scanning microscopy (CLSM) images were also obtained from the baked breads and digital image analysis was conducted on the bread slices. Bread volumes were found to significantly increase for the buckwheat and quinoa breads in comparison with the control. In addition, the pseudocereal-containing breads were characterised by a significantly softer crumb texture effect that was attributed to the presence of natural emulsifiers in the pseudocereal flours and confirmed by the confocal images. No significant differences were obtained in the acceptability of the pseudocereal-containing gluten-free breads in comparison with the control.     

Quality of wheat bread enriched with onion extract and polyphenols content and antioxidant activity changes during bread storage

We determined the effect of onion skin extract (OE) on the quality of wheat bread: contents of total polyphenols and flavonols, antioxidative activity and their changes during storage. With increasing doses of OE to bread, contents of total polyphenols and flavonols and the antioxidative activity were observed to increase. A higher total flavonol content was found in bread with 1% OE stored at 24 °C than in bread stored at 4 °C. There was no such relationship in the bread with 0.5% OE. Changes in flavonols content during storage for 72 h were insignificant. No clear trends of change in the antioxidant activity could be found at storage of breads. The addition of OE caused no changes in the yield and volume of bread and contributed to a decreasing value of L* parameter and to increasing values of ΔE, a* and b* parameters of bread crumb colour. Consumers accepted the smell and taste of bread with the addition of OE to a lesser extent than the control bread. Bread with 1% OE the taste was rated very low. Consumers rated the taste of bread with 1% OE low because it was bitter. Breads enriched with OE had a proper external appearance as well as crumb and crust features. Roasted onion aroma and taste were perceptible in the obtained breads. A bitterness was perceptible in breads baked with the addition of 1% of OE.     

Effect of dietary fibre enrichment on selected properties of gluten-free bread

The enrichment of gluten-free baked products with dietary fibre seems to be necessary since it has been reported that coeliac patients have generally a low intake of fibre due to their gluten-free diet. In the present study different cereal fibres (wheat, maize, oat and barley) were added at 3, 6 and 9 g/100 g level into a gluten-free bread formulation based on corn starch, rice flour and hydroxypropyl methyl cellulose (HPMC). Doughs were evaluated based on consistency, viscosity and thermal properties. Results showed that maize and oat fibre can be added to gluten-free bread with positive impact on bread nutritional and sensory properties. All breads with 9 g/100 g fibre increased the fibre content of control by 218%, but they were rated lower than those with 3 and 6 g/100 g fibre due to their powdery taste. The formulation containing barley fibre produced loaves that had more intense color and volume comparable to the control. During storage of breads a reduction in crumb moisture content and an increase in firmness were observed. The micrographs of the crumb showed the continuous matrix between starch and maize and/or oat fibre obtaining a more aerated structure.     

Fortification of wheat flour with black soldier fly prepupae. Evaluation of technological and nutritional parameters of the intermediate doughs and final baked products

Bread wheat flour presents specific nutrient deficiencies, such as some essential amino acids and this drawback could be tackled by adding ingredients that contain them in high amounts. Therefore, this study aims at developing new types of flours as well as at analysing enriched flours and baked derived products, which combine the compositional and sensory characteristics of wheat bread with some peculiar nutritional properties of black soldier fly prepupae (Hermetia illucens). These composite flours were obtained by mixing “Italian type 1” semi-whole wheat flour (W = 300) with flour obtained from prepupae of black soldier fly (20 g and 40 g/1 kg composite flour). Chemical, physical, and rheological analyses were carried out for each of the flour mixtures. Moisture, ash, gluten, total protein content, falling number, strength, tenacity, extensibility, amino acid profile of doughs and breads were analysed as well. An increase in the content of essential amino acids in doughs and baked products was obtained and also led to an improvement in bread texture.     

Effects of wheat and rye bread structure on mastication process and bolus properties

Chemical composition, baking process and structure of breads influence their degradation in digestion leading to different postprandial responses. Rye bread has a very different structure as compared to wheat bread, and rye breads are known to induce lower postprandial insulin responses than wheat bread. The aim of this study was to find out potential differences in mastication and initial starch hydrolysis rate of rye and wheat breads. Three rye breads (wholemeal rye, endosperm rye and endosperm rye with gluten) and wheat bread were masticated by fifteen participants and the process was monitored using electromyography. The particle size distribution and initial in vitro starch hydrolysis of the bread boluses were analysed. Specific volume correlated negatively and closed porosity of breads correlated positively with work required for mastication. When compared to wheat bread, wholemeal rye bread required more work for mastication process (p = 0.004). Rye breads were degraded to smaller particles than wheat bread during mastication. There was a trend (p = 0.098) towards slower in vitro starch hydrolysis rate in rye bread boluses than in wheat bread boluses. The results indicate that the digestion process of rye breads differs from that of wheat bread already in the early phase of digestion. This may be one reason behind the unique postprandial responses reported for rye breads.     

Effect of fortification of defatted soy flour on sensory and rheological properties of wheat bread

The objective of this study was to determine the effects of soy-fortified bread on the sensory and rheological properties. Ground defatted soy flour was blended with wheat flour at 3%, 7% and 12%. The organoleptic characteristics of soy-fortified wheat breads were carried out by taste panel. The effect of this fortification on the rheological properties of the resulting dough was investigated using farinograph and extensograph for quality assessment of the final product. The ash and protein contents of 3% and 7% wheat–soy bread blends increased compared with control. The results revealed that organoleptic characteristics score such as bendability, appearance, flavour and taste, crust texture and overall acceptability properties of bread containing 3% defatted soy flour was highest even though it is not significantly different. Therefore, we conclude that adding 3% or 7% defatted soy flour actually gives as good a loaf of bread as the 100% wheat bread with higher nutritional quality and acceptable consumer attitude with rheological and sensory characteristics.     

Antioxidative and reducing capacity,macroelements content and sensorial properties of buckwheat‐enhanced gluten‐free bread

Common buckwheat flour (BF) was used to substitute 10%, 20%, 30% and 40% of corn starch, the main component of a gluten‐free bread formula, to make buckwheat‐enhanced gluten‐free breads. The 40% BF‐enhanced gluten‐free bread showed the highest antioxidant capacity against ABTS⁺˙ and DPPH˙ radicals (4.1 and 2.5 μmol Trolox g^?1 DM, respectively) and reducing capacity measured by cyclic voltammetry (1.5 μmol Trolox g^?1 DM). The antioxidant and reducing capacity of buckwheat‐enhanced gluten‐free breads were positively correlated with their total phenolic contents (r = 0.97). The 40% BF‐enhanced gluten‐free bread showed the highest overall sensory quality (7.1 units) when compared to control gluten‐free bread (1.8 units). The linear relationship between applied increasing BF doses in gluten‐free bread formula and magnesium, phosphorus and potassium content in breads was noted. It was concluded that 40% BF‐enhanced gluten‐free bread could be developed and dedicated to those people suffering from coeliac disease.     

Characterization of the Bread Made with Durum Wheat Semolina Rendered Gluten Free by Sourdough Biotechnology in Comparison with Commercial Gluten‐Free Products

Durum wheat semolina was fermented with sourdough lactic acid bacteria and fungal proteases aiming at a complete gluten hydrolysis. The gluten‐free (GF) semolina, added with naturally GF ingredients and structuring agents, was used to produce bread (rendered GF bread; rGFB) at industrial level. An integrated approach including the characterization of the main chemical, nutritional, structural, and sensory features was used to compare rGFB to a gluten‐containing bread and to 5 commercial naturally GF breads. High‐performance liquid chromatography was used for free amino acids (FAAs), organic acids, and ethanol analysis. A methanolic extract was used for determining total phenols and antioxidant activity. The bread characterization also included the analysis of dietary fibers, mycotoxins, vitamins, and heavy metals. Beyond chemical analysis, nutritional profile was evaluated considering the in vitro protein digestibility and the predicted glycemic index, while the instrumental texture profile analysis was performed to investigate the structure and the physical/mechanical properties of the baked goods. Beyond the huge potential of market expansion, the main advantages of durum wheat semolina rendered GF can be resumed in the high availability of FAAs, the high protein digestibility, the low starch hydrolysis index, and the better technological properties of bread compared to the commercial GF products currently present on the market. Vitamins, minerals, and dietary fiber profiles are comparable to those of gluten‐containing wheat bread. Also the sensory profile, determined by a panel test, can be considered the most similar to those of conventional baked goods, showing all the sourdough bread classic attributes.     

Application of Kluyveromyces marxianus, Lactobacillus delbrueckii ssp. bulgaricus and L. helveticus for sourdough bread making

The application of Kluyveromyces marxianus (IFO 288), Lactobacillus delbrueckii ssp. bulgaricus (ATCC 11842) and Lactobacillus helveticus (ATCC 15009) as starter cultures for sourdough bread making was examined. Production of lactic and acetic acids, bread rising, volatile composition, shelf-life and organoleptic quality of the sourdough breads were evaluated. The amount of starter culture added to the flour, the dough fermentation temperature and the amount of sourdough used were examined in order to optimise the bread making process. The use of mixed cultures led to higher total titratable acidities and lactic acid concentrations compared to traditionally made breads. Highest acidity (3.41 g lactic acid/kg of bread) and highest resistance to mould spoilage were observed when bread was made using 50% sourdough containing 1% K. marxianus and 4% L. delbrueckii ssp. bulgaricus. The use of these cultures also improved the aroma of sourdough breads, as shown by sensory evaluations and as revealed by GC–MS analysis.     

Rheological,textural and sensory properties of gluten-free bread formulations based on rice and buckwheat flour

Mixolab, as the rheological instrument, was utilized to create gluten-free products. According to obtained Mixolab profiles, mixtures of rice flour and husked buckwheat and rice flour and unhusked buckwheat flour expressed rheological properties similar to wheat flour. In both types of mixtures the ratio of rice flour to buckwheat flour was 90:10, 80:20 and 70:30. According to the Mixolab profiles of the investigated systems, gluten-free products containing unhusked buckwheat flour had higher water absorption values, lower stability and weaker protein network structure, as well as lower peak viscosity than those consisted of husked buckwheat flour.Increasing the amount of husked buckwheat flour from 10% to 20% resulted in both G′ and yield stress value increase, but further increase of the husked buckwheat flour on 30% resulted in both G′ and yield stress value decrease. However, increasing the amount of unhusked buckwheat flour from 10% to 20% resulted in significant decrease of G′ and yield stress value having no significant impact with the addition of 30% of unhusked buckwheat flour.Hardness, expressed as a work of compression of the final product, increased with the amount of both types of buckwheat flour. Samples containing UBF expressed not significantly higher values of hardness than those prepared with HBF. According to obtained results of sensory evaluation of the final products it can be concluded that all six combinations of tested gluten-free breads were sensory acceptable.     

Rheological properties of gluten-free bread formulations

In this study, the rheological properties of rice bread dough containing different gums with or without emulsifiers were determined. In addition, the quality of rice breads (volume, firmness and sensory analysis) was evaluated. Different gums (xanthan gum, guar gum, locust bean gum (LBG), hydroxyl propyl methyl cellulose (HPMC), pectin, xanthan–guar, and xanthan–LBG blend) and emulsifiers (Purawave^™ and DATEM) were used to find the best formulation for gluten-free breads. Rice dough and wheat dough containing no gum and emulsifier were used as control formulations. The rice dough containing different gums with or without emulsifiers at 25 °C showed shear-thinning behavior with a flow behavior index (n) ranging from 0.33–0.68 (except pectin containing samples) and consistency index (K) ranging from 2.75–61.7 Pa sⁿ. The highest elastic (G′) and loss (G″) module were obtained for rice dough samples containing xanthan gum, xanthan–guar and xanthan–LBG blend with DATEM. When Purawave^™ was used as an emulsifier, dough samples had relatively smaller consistency index and viscoelastic moduli values compared to DATEM. The viscoelastic parameters of rice dough were found to be related to bread firmness. Addition of DATEM improved bread quality in terms of specific volume and sensory values.     

Viability of some probiotic coatings in bread and its effect on the crust mechanical properties

The objective of this study was to obtain functional bread combining the microencapsulation of Lactobacillus acidophilus and starch based coatings. Different probiotic coatings (dispersed or multilayer) were applied onto the surface of partially baked breads. In all treatments, microencapsulated L. acidophilus survived after baking and storage time, although reduction was higher in the sandwich treatment (starch solution/sprayed microcapsules/starch solution). Despite coatings significantly affected the physicochemical properties of the crust, increasing water activity and reducing the failure force, the sensory evaluation revealed a good acceptability of the functional breads. Scanning electron microscopy revealed the presence of scattered microcapsules onto the bread crust, being highly covered in the sandwich coating. Therefore, L. acidophilus included in microcapsules can be incorporated to bread surface through edible coatings, leading functional bread with similar characteristics to common bread, but with additional healthy benefits.     

Development of soy-based bread with acceptable sensory properties

Consumption of soy protein has been associated with benefits related to numerous areas of health. Due to the widespread consumption of bread, one means of contributing to the health of individuals is through the incorporation of soy protein into bread. To this end, soy flour (SF) or soy protein isolates (SPIs) in 20% and 12% substitution levels, respectively, were added to flour during bread manufacture. The developed breads were tested using a consumer panel for acceptability, using a refined white bread as a control. These data were compared to attribute intensity data collected by the trained panel to identify specific flavor and texture characteristics affecting liking. The sensory profile of the 20% SF bread was acceptable and comparable to the control bread, despite a significantly stronger beany flavor. No significant differences in sensory properties of the SF and control breads were detected by the trained panel for many sensory attributes. The SPI bread, however, had a sensory profile that was significantly more firm, dense, sour, beany, bitter, and astringent with a strong aftertaste in comparison to the wheat control bread. Consumer liking scores for the SPI bread was significantly lower than the liking of the control and the SF added bread. PRACTICAL APPLICATION: Many soy-enriched foods, while contributing positively to health, are considered unacceptable by consumers. This is due to negative sensory properties, such as beany, painty, and astringent notes, often perceived by consumers. This study provides information on the level of SF that can be included in bread in an amount that does not detract from consumer acceptability. This level also allows for a Food and Drug Administration (FDA) health claim to be made.