Flour Bread Research Articles

Analysis of Starch in Food Systems by High‐Performance Size Exclusion Chromatography

Starch has unique physicochemical characteristics among food carbohydrates. Starch contributes to the physicochemical attributes of food products made from roots, legumes, cereals, and fruits. It occurs naturally as distinct particles, called granules. Most starch granules are a mixture of 2 sugar polymers: a highly branched polysaccharide named amylopectin and a basically linear polysaccharide named amylose. The starch contained in food products undergoes changes during processing, which causes changes in the starch molecular weight and amylose to amylopectin ratio. The objective of this study was to develop a new, simple, 1-step, and accurate method for simultaneous determination of amylose and amylopectin ratio as well as weight-averaged molecular weights of starch in food products. Starch from bread flour, canned peas, corn flake cereal, snack crackers, canned kidney beans, pasta, potato chips, and white bread was extracted by dissolving in KOH, urea, and precipitation with ethanol. Starch samples were solubilized and analyzed on a high-performance size exclusion chromatography (HPSEC) system. To verify the identity of the peaks, fractions were collected and soluble starch and beta-glucan assays were performed additional to gas chromatography analysis. We found that all the fractions contain only glucose and soluble starch assay is correlated to the HPSEC fractionation. This new method can be used to determine amylose amylopectin ratio and weight-averaged molecular weight of starch from various food products using as low as 25 mg dry samples.

Effect of Cassava Flour Characteristics on Properties of Cassava-Wheat-Maize Composite Bread Types.

Replacement of wheat flour by other kinds of flour in bread making is economically important in South East Africa as wheat is mainly an imported commodity. Cassava is widely available in the region, but bread quality is impaired when large amounts of cassava are used in the bread formulation. Effect of differently processed cassavas (sun-dried, roasted and fermented) on composite cassava-wheat-maize bread quality containing cassava levels from 20 to 40% (w/w) was evaluated in combination with high-methylated pectin (HM-pectin) added at levels of 1 to 3% (w/w) according to a full factorial design. Addition of pectin to cassava flour made it possible to bake bread with acceptable bread quality even at concentration as high as 40%. In addition to cassava concentration, the type of cassava flour had the biggest effect on bread quality. With high level of cassava, bread with roasted cassava had a higher volume compared with sun-dried and fermented. The pectin level had a significant effect on improving the volume in high level roasted cassava bread. Crumb firmness similar to wheat bread could be obtained with sun-dried and roasted cassava flours. Roasted cassava bread was the only bread with crust colour similar to wheat bread.

Physical, Sensory and Microbiological Properties of Wheat-Fermented Unripe Plantain Flour

The physical, sensory and microbiological properties of wheat-fermented unripe plantain composite flour bread were studied. Mature unripe plantain was peeled, sliced, steam blanched, dried and milled into flour. The flour was made into a slurry (10 g of flour/3 ml of water) and allowed to ferment for 24 h. It was then dried, pounded and sieved through 0.25 mm sieve. The fermented unripe plantain flour was then blended with wheat flour in the ratios of (wheat:fermented unripe plantain) 100:0; 90:10; 80:20; 70:30; and 60:40. Bread was produced from the flour blends using the straight dough method. Loaf weight and volume decreased significantly (p < 0.05) with increasing levels of plantain flour inclusion. Sensory evaluation of the flour samples revealed significant differences in the ratings for crumb colour and texture between 100% wheat flour (100:0) and 60% wheat-40% fermented unripe plantain flour (60:40) bread but no significant difference was observed between all bread samples with respect to crust colour, taste, aroma and overall acceptability. The sensory scores showed that all the bread samples were acceptable. Microbiological analysis (total viable count) revealed that all the bread samples were free of microorganisms for up to four days after production.

Selling rice to wheat eaters: the colonial lobby and the promotion of Pain de riz during and after the First World War

This article examines the efforts to promote pain de riz (rice-flour bread) in France during and after the First World War. This effort marked the beginning of the campaign to increase French consumption of Indochinese rice, a campaign that began during the First World War and intensified throughout the 1920s and 1930s. In the face of cultural resistance to rice in France, the Indochina lobby first encouraged the use of rice flour in French bread. The centrality of bread to the French diet and to French national identity seriously complicated the introduction of rice flour. This study expands our understanding of the complex meaning of the whiteness of French bread and the cultural significance of bread's key ingredient: flour. All stages of bread production were heavily regulated in France, and the story of pain de riz reveals how closely various business interests in Indochina and France coordinated with government officials to influence legislation concerning bread's content. In addition, it demonstrat...

Textúra striedky špaldového chleba

The bread quality is considerably dependent on the texture characteristic of bread crumb. Crumb texture is an important quality indicator, as consumer prefer different bread taste. Texture analysis is primarily concerned with the evaluation of mechanical characteristics where a material is subjected to a controlled force from which a deformation curve of its response is generated. It is an objective physical examination of baked products and gives direct information on the product quality, oppositely to dough rheology tests what inform on the baking suitability of the flour, as raw material. This is why the texture analysis is one of the most helpful analytical methods of the product development. In the framework of our research during the years 2008 – 2009 were analyzed selected indicators for bread texture quality of five Triticum spelta L. varieties – Altgold, Oberkulmer Rotkorn, Ostro, Rubiota and Franckenkorn grown in an ecological system. The bread texture quality was evaluated on texture analyzer TA.XT Plus (Stable Micro Systems, Surrey, UK), following the AACC (74-09) standard method and expressed as crumb firmness (N), stiffness (N.mm-1) and relative elasticity (%). Our research proved that all selected indicators were significantly influenced by the year of growing and variety. The most soft bread was achieved in Rubiota, whereas bread crumb samples from Franckenkorn and Altgold were the most firm and stiff. Correlation analysis showed strong negative correlation between relative elasticity and bread crumb firmness as well as bread stiffness (-0.81++, -0.78++). The spelt grain can be a good source for making bread flour, but is closely dependent on choice of spelt variety. The spelt wheat bread crumb texture need further investigation as it can be a reliable quality parameter.

Flour Fortification in South Africa: Post-Implementation Survey of Micronutrient Levels at Point of Retail

Fortification of staple foods is an effective strategy to deliver and increase the intake of micronutrients in the diet and can reduce micronutrient deficiencies. It is important to ensure that the food vehicle consistently contains adequate amounts of nutrients at the point of consumption for effective impact. This survey aimed to gauge the level of fortification of maize and wheat flour at the retail level compared with staple food fortification regulations in South Africa to better understand the current obstacles to effective delivery of micronutrients through flour fortification and consider approaches to strengthening the program. White bread flour and maize meal samples were collected from retail points across all provinces and analyzed for vitamin A, iron, and nicotinamide, and a database capturing the origins of the sample was populated. Nicotinamide and vitamin A results were compared against each other and evaluated against food regulations. The level of compliance with statutory fortification requirements was low, both for bread flour and for maize meal. There is evidence of insufficient addition of premix as opposed to losses due to vitamin A stability as seen from the strong correlation between vitamin A and nicotinamide in maize meal. The current levels of micronutrients added to maize meal and bread flour are unsatisfactory. This is likely to be because of insufficient addition of premix at the mills. This affects the availability and intake by consumers of fortified product and potentially prevents the desired reduction in vitamin and mineral deficiencies expected from the flour fortification program.

Quality and antioxidant properties of breads enriched with dry onion (Allium cepa L.) skin

The aim of the study was to investigate the effect on the antioxidant properties and sensory value of bread of adding ground onion skin (OS). For a determination of bioaccessibility and bioavailability in vitro the human gastrointestinal tract model was used. OS contained mastication-extractable quercetin (4.6mg/g). Quercetin from OS was highly bioaccessible during in vitro conditions, but only approximately 4% of quercetin released during simulated digestion was bioavailable in vitro. The antioxidant potential of bread with OS was significantly higher than the activity noted in the control. In particular, OS addition significantly fortificated bread with bioaccessible lipid oxidation preventers and compounds with reducing and chelating abilities. The 2–3% OS addition caused significant improvement of antioxidant abilities (further increases in the OS supplement did not increase the activity of bread). Sensory evaluation showed that replacement of wheat flour in bread with up to 3% OS powder gave satisfactory consumer acceptability.

Discrimination of Volatiles of Refined and Whole Wheat Bread Containing Red and White Wheat Bran Using an Electronic Nose

The principal objective of this study was to evaluate the capability of electronic (E) nose technology to discriminate refined and whole wheat bread made with white or red wheat bran according to their headspace volatiles. Whole wheat flour was formulated with a common refined flour from hard red spring wheat, blended at the 15% replacement level with bran milled from representative samples of one hard red and 2 hard white wheats. A commercial formula was used for breadmaking. Results varied according to the nature of the sample, that is, crust, crumb, or whole slices. Bread crust and crumb were completely discriminated. Crumb of whole wheat bread made with red bran was distinct from other bread types. When misclassified, whole wheat bread crumb with white bran was almost invariably identified as refined flour bread crumb. Using crust as the basis for comparisons, the largest difference in volatiles was between refined flour bread and whole wheat bread as a group. When refined flour bread crust was misclassified, samples tended to be confused with whole white wheat crust. Samples prepared from whole bread slices were poorly discriminated in general. E-nose results indicated that whole wheat bread formulated with white bran was more similar in volatile makeup to refined flour bread compared to whole wheat bread made with red bran. The E-nose appears to be very capable to accommodate differentiation of bread volatiles whose composition varies due to differences in flour or bran type. Consumer preference of bread made using refined flour in contrast to whole wheat flour is partly due to the different aroma of whole wheat bread. This study used an electronic nose to analyze bread volatiles, and showed that whole wheat bread incorporating white bran was different from counterpart bread made using red bran, and was closer in volatile makeup to "white" bread made without bran. Commercial millers and bakers can take advantage of these results to formulate whole wheat flour with brans of preferred type in order to foster increased consumption of whole wheat products which confer many favorable health benefits.

Evaluation of Baking Properties and Sensory Quality of Wheat-Cowpea Flour

The fortified of soft wheat flour with cowpea flour in bread making was investigated. The Soft wheat flour (SWF) was substituted by cowpea flour at levels of 5, 15 and 20%. The protein content of composite breads ranged from 6.1 - 9.9%. Significant difference was observed in moisture, protein and crude fibre contents of control (wheat bread) and composite bread at 5% addition of cowpea. Water absorption capacities of composite flours increased with increasing levels of cowpea flour in the blend. The specific loaf volume decreased significantly with increased cowpea content of blends. The overall acceptability of the 5% cowpea flour content of composite bread was not significantly different from the control (Soft Wheat-bread) but there is significantly different with increasing the levels of cowpea flour in the blend more than 5%. Keywords—Cowpea flour, wheat flour, baking properties, sensory quality.

Evaluation of Wheat Flour Bread Fortified With Dried Mushroom

Evaluation of Wheat Flour Bread Fortified With Dried Mushroom

Colour Assessment on Bread Wheat and Triticale Fresh Pasta

Although durum wheat is the cereal of choice for pasta production, in many areas of Argentina pasta is made from bread wheat, since durum wheat is cultivated only in a small region of the country. The purpose of this work was to determine the influence of different bread flours on the colour of laminated fresh pasta. Triticale flour was also studied. In addition, ash, protein, and protein fractions of each flour were measured. Also, the formulation was modified using different gluten, starch, and water concentrations. Pasta lightness and redness were affected mainly by the ash content, while yellowness was affected by the protein content of different flours. A similar effect was found when the formulation was substituted for starch and gluten, due to protein dilution and concentration, respectively. Albumins and globulins correlated with a* component, while gliadins, soluble and insoluble glutenins correlated with b* component; however, only glutenins presented correlation with colour score (CS = [L* + (b* × 2)]/20). The greatest amount of water added to the dough produced a decrease of lightness and an increase of redness and yellowness of pasta samples. The overall ANOVA revealed that the greatest sources of variation for pasta colour were the different flours used, in comparison with the effect of starch and gluten substitution, and with the addition of different amounts of water.

Wheat Proteins—The Foundation of Breadmaking

In different breadmaking processes the methods for mixing and processing dough vary and, in principle, so should the qualities of the proteins present in the flour. It has long been known that flour (gluten) content and quality underpin bread quality, but we are still learning about the microscopic processes that ultimately control bread quality. The relationship between flour characteristics and bread volume has understandably been a key area of study, but perhaps we should be paying more attention to the interactions between dough and the processing methods used to turn dough into bread. Examples provided in the column demonstrate that flour protein has many different roles to play in delivering the bread quality that bakers and consumers seek. Because flour protein is vital to breadmaking, we must understand how to use it wisely.

Influence of maize flour particle size on gluten‐free breadmaking

Maize, one of the suitable grains for coeliac consumption, is, together with rice, the most cultivated cereal in the world. However, the inclusion of maize flour in gluten-free bread is a minority and studies are scarce. This paper analyses the influence of different maize flour types and their particle sizes on the quality of two types of bread without gluten (80% and 110% water in the formulation) obtained from them. We also analysed the microstructure of the dough and its behaviour during the fermentation. Finer flours had a lower dough development during fermentation in all cases. Among the different types of flour, those whose microstructure revealed compact particles were those which had higher specific bread volume, especially when the particle size was greater. Among the formulations, the dough with more water gave breads with higher specific volume, an effect that was more important in more compact flours. The higher volume breads had lower values of hardness and resilience. The type of corn flour and mainly its particle size influence significantly the dough development of gluten-free bread during fermentation and therefore the final volume and texture of the breads obtained. The flours having coarser particle size are the most suitable for making gluten-free maize bread.

Effect of ginseng powder addition on physicochemical properties of wheat bread and cookies

This study evaluated quality properties of hard wheat-ginseng bread (10% ginseng powder, GP) and soft wheat-ginseng cookies (10% GP), and changes in ginsenosides (G) in bread and cookies upon baking. Bread loaf volume decreased when GP was added to hard wheat flour (HWF) bread formulations. Widths of cookies baked from soft wheat flour (SWF)-GP were significantly smaller than those of cookies baked from SWF. Individual G (Rb1, Rc, Rd, Rg2, and Rg3) were fractionated and identified by reversed-phase (RP)-HPLC from GP, ground bread crust, and ground bread crumb of samples baked from HWF and HWF-GP, and ground cookie samples baked from SWF and SWF-GP. Rg2 (0.17 and 0.06 mg/100 mg GP) was found in the bread crust and bread crumb of samples baked from HWF-GP, respectively, whereas Rg3 (0.07 mg/100 mg GP) was present only in the bread crust. Rg2 and Rg3 were not present in cookie samples baked from SWF-GP.

Alkylresorcinols in Latvian and Finnish breads

The alkylresorcinol (AR) content and relative homologue composition were determined in 9 Latvian and 11 Finnish soft breads. ARs were extracted with hot 1-propanol and quantified, using a gas chromatography-mass spectrometry method. The total AR content (μg/g dry matter) varied from 560 to 840 in rye breads, from 500 to 700 in Finnish mixed rye and wheat flour breads, from 200 to 300 in Latvian mixed rye and wheat flour breads and from 25 to 30 in white wheat breads. Rye and white wheat breads in the two countries varied only slightly in AR content, but there were wide variations in AR content in mixed flour breads. The AR contents in soft breads could be indicators of bran or fibre content, but not of whole-grain flour content.

Effect of Bambara Groundnut Flour (Vigna subterranea (L.) Verdc.) Supplementation on Chemical, Physical, Nutritional and Sensory Evaluation of Wheat Bread

Bambara groundnut (Vigna subterrenea (L) Verdc) is a major source of vegetable protein in sub-Saharan Africa. And the aim of this study was to enhance the nutritional value of wheat bread through the addition of bambara groundnut flour to wheat four. For this, bambara groundnut seeds were soaked in tap water, manually decorticated, sun dried and milled into fine flour. Proximate analysis of flours of de-hulled bambara groundnut and wheat were conducted. Flour of de-hulled bambara groundnut was used for bread supplementation in ratios of 5, 10 and 15%. Rheological properties of the control flour and wheat flour supplemented with 10% of de-hulled bambara groundnut flour were conducted. The total area and dough development time increased. However, water absorption, stability and extensibility respectively decreased, from 71.3; 8.5; 190 in the control flour to 71.0; 5.5; 180 in the 10% supplemented flour. The increases in the resistance to extension and proportional number from 260 to 280 and 1.37 to 1.56, respectively resulted in stiff dough. The most important effect of wheat bread supplementation was the improvement of protein quantity from 13.74 +/- 0.02% for the control bread to 15.49 +/- 0.02, 17.00 +/- 0.05 and 18.98 +/- 0.02% for the 5, 10 and 15% blending ratios, respectively. The in-vitro protein digestibility progressively increased from 84.33 +/- 0.03 in the control bread to 85.42 +/- 0.04, 86.57 +/- 0.04 and 87.64 +/- 0.03 in breads containing 5, 10 and 15% bambara groundnut flour. The sensory attributes of different types of bread showed that, a significant difference was observed in texture, colour and overall acceptability. However, the panelists gave higher score for 10% de-hulled bambara groundnut flour bread than bread made from other blends. The loaf weights, loaf volume and specific volume increased. However, while the loaf weight increased with addition of 15% de-hulled bambara groundnut flour, both of loaf volume and specific volume decreased. Nutritional value of wheat bread can be enhanced by the addition of de-hulled bambara groundnut flour at a level of up to 10%.

Characterisation of volatile compounds of lupin protein isolate‐enriched wheat flour bread

The influence of lupin protein isolate (LPI) on the volatile fraction of wheat flour (WF) bread was investigated. Headspace solid-phase microextraction technique (HS-SPME) coupled to the gas chromatography–mass spectrometry (GC–MS) analysis was applied to characterise volatile compounds of both crust and crumb. In a preliminary sensory experiment, LPI was found to have a modifying effect on the odour of WF-bread. The most important odorants of WF and LPI-containing wheat flour (LWF) breads were evaluated on the basis of detection frequency analysis. Fifty three compounds were detected by more than five judges, ten of which were detected only in LWF bread. The most important compounds of LPI-containing crumb and crust were vinylpyrazine, hexanal, 2-propylpyrazine, 2-octenal, 2,3-butanedione, 2,5-dimethylpyrazine, non-identified compounds with green, mushroom-like or pleasant odour and pyrazines. Their presence was attributed either to oxidative degradation of fatty acids or thermal reactions. Most of these compounds contributed to the aroma character of LPI-bread with green, earthy, malty, buttery and roasted notes.

The anti-staling effect of pre-gelatinized flour and emulsifier in gluten-free bread

The use of gluten-free products is increasing since an increasing number of people (1–2 %) are suffering from Celiac disease and thereby need a gluten-free diet. Gluten-free bread tends to have shorter shelf life and quality compared with white wheat bread. In this study, 3 % (flour basis) of pre-gelatinized oat and barley flour as well as an emulsifier were added to a gluten-free mix to increase the water content by 1.5–2 %, affect the starch retrogradation and the formation of amylose lipid complex. The staling was followed measuring the firmness (texture analyzer), water content and distribution (nuclear magnetic resonance), amylopectin retrogradation and the formation of amylose–lipid complex (differential scanning calorimetry) in order to see the impact of both macroscopic and molecular changes on firmness. Both gluten-free bread and a white wheat bread were used as control loaves. Largest specific volume was found in the gluten-free control. The firmness varied with both the specific volume and the point of measurement. The amount of retrograded amylopectin increased the firmness, although this effect was dependent on the type of bread, in terms of distribution and availability of the water within the system. The proton relaxation time, which was representing movable water, decreased during storage and revealed that both the amylopectin retrogradation and the lipid complex formation were affecting the rigidity of the amorphous domain and not only the crystalline regions. In contrast to the other recipes, the use of emulsifier caused limited retrogradation and a low correlation between the texture properties and time-dependent events.

Effect of legume flours on baking characteristics of gluten-free bread

The objective of this work was to study the characteristics of four gluten-free bread formulations and the possibility of substituting soya protein with other legume proteins. Four bread recipes were prepared with chickpea flour, pea isolate, carob germ flour or soya flour. Carob germ flour batter structure was thicker compared with the other batters, probably due to the different protein behaviour and the residual gums present in carob germ flour. However, carob germ flour bread obtained the lowest specific volume values (2.51 cm3/g), while chickpea bread obtained the highest (3.26 cm3/g). Chickpea bread also showed the softest crumb. Confocal scanning-laser microscopy results showed a more compact microstructure in carob germ flour bread compared with soya and chickpea formulations. Chickpea bread exhibited the best physico-chemical characteristics and, in general, good sensory behaviour, indicating that it could be a promising alternative to soya protein.

Development and Validation of Two Competitive ELISAs for the Detection of Potentially Allergenic Lupine (Lupinus Species) in Food

The paper presents two competitive enzyme linked immunosorbent assays (ELISAs) for the detection of lupine proteins in foods. The ELISAs are based on anti-lupine antibodies produced in a rabbit (IgG) and in a chicken (IgY), respectively. Cross-reactivity tests with 33 foods of plant origin revealed that both ELISAs show slight cross-reactivity (≤1.5 %) with pecan nut. They do, however, not cross-react with 32 species potentially used in lupine containing foodstuffs. Both ELISAs detect proteins from white (Lupinus albus) and blue (Lupinus angustifolius) lupine and, with a lower sensitivity, proteins from yellow (Lupinus luteus) lupine. Matrix effects could be eliminated by diluting the sample extracts 1:10 before loading them onto the microtiter plate. The IgG ELISA allows the detection of 50 ppm white lupine flour in bread, vegetarian patties and rusk. With the IgY ELISA, lupine can be detected in vegetarian patties and bread at the 50 ppm spiking level and in rusk at the 100 ppm spike level.