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Jan A. Delcour - One of the best experts on this subject based on the ideXlab platform.
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the role of non starch polysaccharides in determining the air water interfacial properties of wheat rye and Oat dough liquor constituents
Food Hydrocolloids, 2020Co-Authors: Frederik Janssen, Arno G.b. Wouters, Paula Moldenaers, Jan Vermant, Yannick Meeus, Jan A. DelcourAbstract:Abstract Dough gas cell stability is a prerequisite for obtaining Breads with high specific volume and homogeneous crumb. The contribution of cereal endogenous non-starch polysaccharides (NSPs) to gas cell stability during wheat, rye, and Oat Bread making is still unclear. In this work, the aqueous phases from their fermented doughs were isolated as dough liquor (DL) by ultracentrifugation. The foaming, bulk shear rheology, and air-water (A-W) interfacial properties of wheat and rye DLs (treated with and without endoxylanase) and Oat DL (treated with and without both lichenase and β- d -glucosidase) were studied. Enzymatic hydrolysis drastically reduced the apparent bulk shear viscosity of the different DLs and resulted in increased and decreased moduli (or magnitude) of the complex A-W interfacial shear viscosities of wheat and rye DLs, respectively. The latter implies that (non-hydrolyzed) rye DL arabinoxylan strengthens the A-W interfacial film consisting of adsorbed proteins and lipids. No measurable A-W interfacial shear viscosities were obtained for Oat DL irrespective of whether its β-D-glucans were hydrolyzed or not. This is probably because lipids dominate the Oat DL A-W interfaces. The knowledge generated provides a fundamental basis for specifically modifying the composition of the aqueous phase in wheat, rye, and Oat doughs to improve the quality of mixed cereal Breads.
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The role of lipids in determining the air-water interfacial properties of wheat, rye, and Oat dough liquor constituents.
Food Chemistry, 2020Co-Authors: Frederik Janssen, Arno G.b. Wouters, Lize Linclau, Etienne Waelkens, Rita Derua, Jonas Dehairs, Paula Moldenaers, Jan Vermant, Jan A. DelcourAbstract:Abstract Bread is mainly made from wheat but also from other cereals such as rye and Oats. We here report on the role of dough liquor (DL) proteins and lipids in determining the stability of gas cell air-water (A-W) interfaces in wheat, rye, and Oat Bread making. Surprisingly, most lipids in DLs of these cereals are nonpolar. Their main polar DL lipids are phospholipids. Lipids at wheat and rye DL stabilized A-W interfaces impair interactions between its proteins, as reflected by an increased A-W interfacial shear viscosity of the adsorbed film upon defatting. In contrast, removing most lipids from Oat DL pronouncedly increased the A-W interface surface tension, demonstrating that lipids are the prominent adsorbed species.
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impact of water extractable components from different cereals on the quality of Oat Bread
Journal of Cereal Science, 2018Co-Authors: Anneleen Pauly, Jan A. DelcourAbstract:Abstract Loaf volume and crumb structure of Oat Bread are not comparable to those of Bread from wheat flour. Hydrocolloids, surfactants and/or enzymes are often included in Oat batter recipes for quality enhancement reasons. In this study, we examined the impact of water-extractable components from barley, Oat, rye and wheat flour on Oat Bread quality. We speculated that such water extracts contain components which also would enhance the quality of Oat Bread. As expected, extract protein, non-starch polysaccharide, lipid and enzyme levels varied widely amongst the different cereal flours used. The extracts also varied in foaming properties and extract viscosities. Rye flour contained the highest level of water-extractable components. Inclusion of rye aqueous extract resulted in the largest loaf volume increase and in softer crumb than noted for control Oat Bread. Rheofermentometer analyses showed that the moment of gas cell opening was delayed when rye extract was added, indicating improved batter gas cell stabilization, while collapse during baking was not affected. The Oat Bread improving effect of the rye extract is likely due to a combination of the impact of different of its constituents such as enzymes and surface active components.
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partial purification of components in rye water extractables which improve the quality of Oat Bread
Journal of Cereal Science, 2018Co-Authors: Anneleen Pauly, Jan A. DelcourAbstract:Abstract Unlike wheat Bread, the dough of which has a visco-elastic network and high gas-holding capacity, Oat Bread generally has a low volume and a dense structure. We showed earlier that including rye water-extractable components in an Oat Bread batter recipe increases loaf volume by ca. 30% (Pauly and Delcour, submitted as back-to-back publication). We here report on efforts to identify the active factor(s). Anion exchange chromatography allowed enriching the active factor(s). This and the fact that only a limited volume increase was observed when Oat batter was supplemented with boiled rye extract indicate that proteins are likely the most important components responsible for the volume increase. While the most active factor(s) had a pI below 4.5, components with pI values between 4.5 and 8.5 also contributed to Oat loaf volume. Alkaline rye components (pI > 8.5) or rye arabinoxylan had no impact. Rye water-extractable components smaller than 6–8 kDa also had a positive impact on loaf volume.
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physical and molecular changes during the storage of gluten free rice and Oat Bread
Journal of Agricultural and Food Chemistry, 2014Co-Authors: Anna-Sophie Hager, Geertrui M. Bosmans, Jan A. DelcourAbstract:Gluten-free Bread crumb generally firms more rapidly than regular wheat Bread crumb. We here combined differential scanning calorimetry (DSC), texture analysis, and time-domain proton nuclear magnetic resonance (TD 1H NMR) to investigate the mechanisms underlying firming of gluten-free rice and Oat Bread. The molecular mobility of water and biopolymers in flour/water model systems and changes thereof after heating and subsequent cooling to room temperature were investigated as a basis for underpinning the interpretation of TD 1H NMR profiles of fresh crumb. The proton distributions of wheat and rice flour/water model systems were comparable, while that of Oat flour/water samples showed less resolved peaks and an additional population at higher T2 relaxation times representing lipid protons. No significant crumb moisture loss during storage was observed for the gluten-free Bread loaves. Crumb firming was mainly caused by amylopectin retrogradation and water redistribution within Bread crumb. DSC, texture, ...
Tamer H Gamel - One of the best experts on this subject based on the ideXlab platform.
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effect of yeast fermented and sour dough making processes on physicochemical characteristics of β glucan in whole wheat Oat Bread
Lwt - Food Science and Technology, 2015Co-Authors: Tamer H Gamel, Elsayed M Abdelaal, Susan M ToshAbstract:Abstract Consumption of Breads containing whole grains or functional ingredients rich in dietary fiber and β-glucans has shown a dramatic increase because of their health benefits. Since bioactivity of β-glucan has been linked with its physicochemical properties, the current study was designed to investigate the effects of straight-, sponge- and sour-dough Bread making processes on physicochemical characteristics of β-glucan in whole wheat/Oat Bread. The presence of β-glucan-degrading enzymes in the whole wheat flour used in this study were found to depolymerize β-glucan at a rate of 0.054 min −1 , causing a significant reduction in β-glucan molecular weight ( M w ) during dough process. Sour- and sponge-doughs had lower rates of β-glucan depolymerization, resulting in Breads with medium to high β-glucan M w range (600–1087 kg/mol) compared to straight-dough method. Dough pH, titratable acidity and fermentation plus proofing time showed significant impacts on β-glucan M w and viscosity, but not on solubility. Acetic and propionic acids were present in all doughs, whereas lactic acid was only found in sour-dough. Generally, sour-dough Bread showed better potential over yeast-fermented Breads in terms of preserving β-glucan M w and viscosity during baking process when a blend of whole wheat flour and Oat bran was used.
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Effect of yeast-fermented and sour-dough making processes on physicochemical characteristics of β-glucan in whole wheat/Oat Bread
Lwt - Food Science and Technology, 2014Co-Authors: Tamer H Gamel, El-sayed M. Abdel-aal, Susan M ToshAbstract:Abstract Consumption of Breads containing whole grains or functional ingredients rich in dietary fiber and β-glucans has shown a dramatic increase because of their health benefits. Since bioactivity of β-glucan has been linked with its physicochemical properties, the current study was designed to investigate the effects of straight-, sponge- and sour-dough Bread making processes on physicochemical characteristics of β-glucan in whole wheat/Oat Bread. The presence of β-glucan-degrading enzymes in the whole wheat flour used in this study were found to depolymerize β-glucan at a rate of 0.054 min −1 , causing a significant reduction in β-glucan molecular weight ( M w ) during dough process. Sour- and sponge-doughs had lower rates of β-glucan depolymerization, resulting in Breads with medium to high β-glucan M w range (600–1087 kg/mol) compared to straight-dough method. Dough pH, titratable acidity and fermentation plus proofing time showed significant impacts on β-glucan M w and viscosity, but not on solubility. Acetic and propionic acids were present in all doughs, whereas lactic acid was only found in sour-dough. Generally, sour-dough Bread showed better potential over yeast-fermented Breads in terms of preserving β-glucan M w and viscosity during baking process when a blend of whole wheat flour and Oat bran was used.
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changes of β glucan physicochemical characteristics in frozen and freeze dried Oat bran Bread and porridge
Journal of Cereal Science, 2013Co-Authors: Tamer H Gamel, Kaitlin Badali, Susan M ToshAbstract:Abstract The ability of Oat foods to lower serum cholesterol and post-prandial blood glucose concentrations has been linked to the physicochemical properties of the bioactive component, mixed linkage β-glucan. Oat foods frequently need to be shipped or stored prior to analysis and β-glucan characteristics may change over time. Reductions in β-glucan solubility or molecular weight lead to lower viscosity development which decreases bioactivity. Impact of freezing and freeze drying conditions on the β-glucan physicochemical characteristics in Oat bran Bread and porridge were studied. Two in vitro digestibility methods were used to produce physiological extracts and the results were compared. The β-glucan molecular weight, solubility and viscosity for Oat Bread stored at room temperature were unchanged for 3 days, followed by a gradual decline in these parameters. The extract viscosity for Bread decreased significantly after freezing at −80 °C and freeze drying after freezing at −18 and −80 °C, whereas freezing in liquid nitrogen did not significantly influence viscosity. Freezing of Oat bran porridge did not affect extract viscosity, but freeze drying resulted in reduction of extract viscosity compared to the fresh porridge. Freezing and freeze drying did not dramatically affect the molecular weight or solubility of β-glucan in either product. The rapid visco analyzer was more effective and reliable for sample digestion than when physiological extraction was conducted in the shaking water bath. Generally, freezing at −18 °C or by submersion in liquid nitrogen maintained the physicochemical characteristics of β-glucan in food products either for commercial products or subsequent analysis.
Susan M Tosh - One of the best experts on this subject based on the ideXlab platform.
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effect of yeast fermented and sour dough making processes on physicochemical characteristics of β glucan in whole wheat Oat Bread
Lwt - Food Science and Technology, 2015Co-Authors: Tamer H Gamel, Elsayed M Abdelaal, Susan M ToshAbstract:Abstract Consumption of Breads containing whole grains or functional ingredients rich in dietary fiber and β-glucans has shown a dramatic increase because of their health benefits. Since bioactivity of β-glucan has been linked with its physicochemical properties, the current study was designed to investigate the effects of straight-, sponge- and sour-dough Bread making processes on physicochemical characteristics of β-glucan in whole wheat/Oat Bread. The presence of β-glucan-degrading enzymes in the whole wheat flour used in this study were found to depolymerize β-glucan at a rate of 0.054 min −1 , causing a significant reduction in β-glucan molecular weight ( M w ) during dough process. Sour- and sponge-doughs had lower rates of β-glucan depolymerization, resulting in Breads with medium to high β-glucan M w range (600–1087 kg/mol) compared to straight-dough method. Dough pH, titratable acidity and fermentation plus proofing time showed significant impacts on β-glucan M w and viscosity, but not on solubility. Acetic and propionic acids were present in all doughs, whereas lactic acid was only found in sour-dough. Generally, sour-dough Bread showed better potential over yeast-fermented Breads in terms of preserving β-glucan M w and viscosity during baking process when a blend of whole wheat flour and Oat bran was used.
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Effect of yeast-fermented and sour-dough making processes on physicochemical characteristics of β-glucan in whole wheat/Oat Bread
Lwt - Food Science and Technology, 2014Co-Authors: Tamer H Gamel, El-sayed M. Abdel-aal, Susan M ToshAbstract:Abstract Consumption of Breads containing whole grains or functional ingredients rich in dietary fiber and β-glucans has shown a dramatic increase because of their health benefits. Since bioactivity of β-glucan has been linked with its physicochemical properties, the current study was designed to investigate the effects of straight-, sponge- and sour-dough Bread making processes on physicochemical characteristics of β-glucan in whole wheat/Oat Bread. The presence of β-glucan-degrading enzymes in the whole wheat flour used in this study were found to depolymerize β-glucan at a rate of 0.054 min −1 , causing a significant reduction in β-glucan molecular weight ( M w ) during dough process. Sour- and sponge-doughs had lower rates of β-glucan depolymerization, resulting in Breads with medium to high β-glucan M w range (600–1087 kg/mol) compared to straight-dough method. Dough pH, titratable acidity and fermentation plus proofing time showed significant impacts on β-glucan M w and viscosity, but not on solubility. Acetic and propionic acids were present in all doughs, whereas lactic acid was only found in sour-dough. Generally, sour-dough Bread showed better potential over yeast-fermented Breads in terms of preserving β-glucan M w and viscosity during baking process when a blend of whole wheat flour and Oat bran was used.
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changes of β glucan physicochemical characteristics in frozen and freeze dried Oat bran Bread and porridge
Journal of Cereal Science, 2013Co-Authors: Tamer H Gamel, Kaitlin Badali, Susan M ToshAbstract:Abstract The ability of Oat foods to lower serum cholesterol and post-prandial blood glucose concentrations has been linked to the physicochemical properties of the bioactive component, mixed linkage β-glucan. Oat foods frequently need to be shipped or stored prior to analysis and β-glucan characteristics may change over time. Reductions in β-glucan solubility or molecular weight lead to lower viscosity development which decreases bioactivity. Impact of freezing and freeze drying conditions on the β-glucan physicochemical characteristics in Oat bran Bread and porridge were studied. Two in vitro digestibility methods were used to produce physiological extracts and the results were compared. The β-glucan molecular weight, solubility and viscosity for Oat Bread stored at room temperature were unchanged for 3 days, followed by a gradual decline in these parameters. The extract viscosity for Bread decreased significantly after freezing at −80 °C and freeze drying after freezing at −18 and −80 °C, whereas freezing in liquid nitrogen did not significantly influence viscosity. Freezing of Oat bran porridge did not affect extract viscosity, but freeze drying resulted in reduction of extract viscosity compared to the fresh porridge. Freezing and freeze drying did not dramatically affect the molecular weight or solubility of β-glucan in either product. The rapid visco analyzer was more effective and reliable for sample digestion than when physiological extraction was conducted in the shaking water bath. Generally, freezing at −18 °C or by submersion in liquid nitrogen maintained the physicochemical characteristics of β-glucan in food products either for commercial products or subsequent analysis.
Elke K. Arendt - One of the best experts on this subject based on the ideXlab platform.
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in vitro starch digestibility and predicted glycaemic indexes of buckwheat Oat quinoa sorghum teff and commercial gluten free Bread
Journal of Cereal Science, 2013Co-Authors: Anika Wolter, Anna-Sophie Hager, Emanuele Zannini, Elke K. ArendtAbstract:Abstract The in vitro starch digestibility of five gluten-free Breads (from buckwheat, Oat, quinoa, sorghum or teff flour) was analysed using a multi-enzyme dialysis system. Hydrolysis indexes (HI) and predicted glycaemic indexes (pGI) were calculated from the area under the curve (AUC; g RSR/100g TAC*min) of reducing sugars released (RSR), and related to that of white wheat Bread. Total available carbohydrates (TAC; mg/4 g Bread “as eaten”) were highest in sorghum (1634 mg) and Oat Bread (1384 mg). The AUC was highest for quinoa (3260 g RSR), followed by buckwheat (2377 g RSR) and teff Bread (2026 g RSR). Quinoa Bread showed highest predicted GI (95). GIs of buckwheat (GI 80), teff (74), sorghum (72) and Oat (71) Breads were significantly lower. Significantly higher gelatinization temperatures in teff (71 °C) and sorghum flour (69 °C) as determined by differential scanning calorimetry (DSC) correlated with lower pGIs (74 and 72). Larger granule diameters in Oat (3–10 μm) and sorghum (6–18 μm) in comparison to quinoa (1.3 μm) and buckwheat flour (3–7 μm) as assessed with scanning electron microscopy resulted in lower specific surface area of starch granules. The data is in agreement with predictions that smaller starch granules result in a higher GI.
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rheological properties and Bread making performance of commercial wholegrain Oat flours
Journal of Cereal Science, 2010Co-Authors: Fabio Dal Bello, Edith K. Hüttner, Elke K. ArendtAbstract:Three commercial wholegrain Oat (WO) flours from Finland (WOF), Ireland (WOI) and Sweden (WOS) were evaluated for their Bread making ability with the objective of finding predictive relationships between flour physicochemical properties and Bread quality. Overall, significant differences were found in the Bread making properties of the WO flours. Good Bread quality was obtained when using WOS and WOI flour since Breads showed high specific loaf volume and slice height as well as low density and hardness. Low quality Breads were obtained when WOF flour was used. In addition, positive effects on Oat Bread quality were observed for low batter viscosity and high deformability, as obtained for WOS and WOI. Based on the physicochemical analysis of the flours, water hydration capacity was found to be the main reason for increased elasticity of WOF batters. Small flour particle size, damaged starch granules and high protein content were identified as the key factors causing increased water hydration capacity. These findings suggest that WO flours with coarse particle size, limited starch damage and low protein content result in superior Oat Bread quality.
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oxidative and proteolytic enzyme preparations as promising improvers for Oat Bread formulations rheological biochemical and microstructural background
Food Chemistry, 2010Co-Authors: Stefano Renzetti, Christophe M Courtin, Jan A. Delcour, Elke K. ArendtAbstract:Commercial preparations of laccase (LAC) and glucose oxidase (GO) (0.01% and 0.1% addition levels), as well as of a protease (PR) (0.001% and 0.01% addition levels) were tested for their impact on the Breadmaking performance of gluten-free Oat flour. LAC 0.1%, PR 0.001% and PR 0.01% additions significantly improved Oat Bread quality, as they increased specific volume and decreased crumb hardness and chewiness. In contrast, GO 0.1% addition revealed detrimental effects, as it resulted in the hardest Bread crumb. The improved Breadmaking performances of Oat Breads with LAC and PR addition was explained by the increase in batter softness, deformability and elasticity which were achieved upon addition of these enzyme preparations, both containing discernible levels of endo-β-glucanase side activity. With LAC, the effect is due to prevalence of β-glucan depolymerisation over protein polymerisation while, with PR, it is due to the combined effect of protein and β-glucan degradation. Extensive protein hydrolysis during baking may have increased functionality of the soluble protein fraction. In contrast, extensive protein polymerisation was detrimental, as indicated by GO addition.
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Identification of lactic acid bacteria isolated from Oat sourdoughs and investigation into their potential for the improvement of Oat Bread quality
European Food Research and Technology, 2010Co-Authors: Edith K. Hüttner, Fabio Bello, Elke K. ArendtAbstract:The use of sourdough in wheat and rye Breads has been extensively studied; however, little is known about its potential effect when baking Oat Bread. Consequently, the impact of sourdough on Oat Bread quality was investigated. Two different sourdoughs were prepared from wholegrain Oat flour without the addition of starter cultures, by continuous propagation at 28 (SD 28) or 37 °C (SD 37) until the composition of the lactic acid bacteria remained stable. The dominant LAB were identified by sequence analysis of the 16S rDNA isolated from pure cultures. LAB from SD 28 belonged to the species Leuconostoc argentinum , Pedicoccus pentosaceus and Weissella cibaria , while Lactobacillus coryniformis dominated SD 37. The isolated LAB were further used as starter cultures for the production of Oat sourdoughs. Fundamental rheology revealed softening of the sourdoughs compared to non-acidified and chemically acidified controls, which could not be attributed to proteolytic activity. Incorporation of Oat sourdough into an Oat Bread recipe resulted in significantly increased loaf-specific volume as well as improved texture, independent of addition level or sourdough type. Overall, the results of this study show that sourdoughs containing lactic acid bacteria isolated from Oats have the potential to enhance Oat Bread quality.
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Fundamental study on the effect of hydrostatic pressure treatment on the Bread-making performance of Oat flour
European Food Research and Technology, 2010Co-Authors: Edith K. Hüttner, Fabio Bello, Elke K. ArendtAbstract:The effect of hydrostatic pressure (HP) has been investigated on cereal starches, proteins and flour systems, but its efficacy in cereal food processing has not been established. This study describes the use of HP as a tool to improve the Bread-making performance of Oat flour. For this purpose, Oat batters were HP-treated at 200, 350 or 500 MPa, and the microstructure was investigated using scanning electron microscopy and bright field microscopy. Furthermore, HP-treated Oat batters were added to an Oat-Bread recipe, replacing 10, 20 or 40% of untreated Oat flour. Breads analysis revealed significantly improved Bread volume upon addition of 10% Oat batter treated at 200 MPa. The staling rate was reduced of all Breads containing Oat batter treated at 200 MPa. In contrast, Bread quality deteriorated due to addition of Oat batters treated at pressures ≥350 MPa, independent of the addition level. Overall, weakening of the protein structure, moisture redistribution and possibly changed interactions between proteins and starch were responsible for the positive effects of HP-treatment at 200 MPa on the Bread-making performance of Oat flour. Protein network formation and pre-gelatinisation of starch did not improve Oat-Bread quality.
Elke Karin Arendt - One of the best experts on this subject based on the ideXlab platform.
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Physicochemical properties of Oat varieties and their potential for Breadmaking
Cereal Chemistry, 2011Co-Authors: Edith K. Hüttner, Fabio Dal Bello, Steffen Beuch, Emanuele Zannini, Jean Titze, Elke Karin ArendtAbstract:ABSTRACT The Breadmaking potential of six Oat varieties was compared with and related to their physicochemical properties. The most significant differences in the Bread characteristics were found in the crumb structure. The varieties Buggy, Energie, and Zorro resulted in good Bread quality with an even gas-cell distribution characterized by a high number of relatively small pores. In contrast, Typhon, Ivory, and Nord 08/311 each had a large hole in the center of the crumb and accordingly poor quality. Breads differed little in specific volume, bake loss, and density. Rheological analysis revealed positive effects of low batter resistance to deformation on Oat Bread quality. On the basis of the physicochemical characterization, protein and fat contents were identified as key factors responsible for differences observed in Bread quality, provided that starch damage and water-hydration capacity were low. Additionally, high setback and final viscosity, as determined by Rapid Visco Analyser (RVA) analysis, pos...
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Rheological properties and Bread making performance of commercial wholegrain Oat flours
2010Co-Authors: Edith K. H??ttner, Fabio Dal Bello, Elke Karin ArendtAbstract:Three commercial wholegrain Oat (WO) flours from Finland (WOF), Ireland (WOI) and Sweden (WOS) were evaluated for their Bread making ability with the objective of finding predictive relationships between flour physicochemical properties and Bread quality. Overall, significant differences were found in the Bread making properties of the WO flours. Good Bread quality was obtained when using WOS and WOI flour since Breads showed high specific loaf volume and slice height as well as low density and hardness. Low quality Breads were obtained when WOF flour was used. In addition, positive effects on Oat Bread quality were observed for low batter viscosity and high deformability, as obtained for WOS and WOI. Based on the physicochemical analysis of the flours, water hydration capacity was found to be the main reason for increased elasticity of WOF batters. Small flour particle size, damaged starch granules and high protein content were identified as the key factors causing increased water hydration capacity. These findings suggest that WO flours with coarse particle size, limited starch damage and low protein content result in superior Oat Bread quality. ?? 2010 Elsevier Ltd. All rights reserved.
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Identification of lactic acid bacteria isolated from Oat sourdoughs and investigation into their potential for the improvement of Oat Bread quality
2010Co-Authors: Edith K. Hüttner, F. Dal Bello, Elke Karin ArendtAbstract:The use of sourdough in wheat and rye Breads has been extensively studied; however, little is known about its potential effect when baking Oat Bread. Consequently, the impact of sourdough on Oat Bread quality was investigated. Two different sourdoughs were prepared from wholegrain Oat flour without the addition of starter cultures, by continuous propagation at 28 (SD 28) or 37 °C (SD 37) until the composition of the lactic acid bacteria remained stable. The dominant LAB were identified by sequence analysis of the 16S rDNA isolated from pure cultures. LAB from SD 28 belonged to the species Leuconostoc argentinum, Pedicoccus pentosaceus and Weissella cibaria, while Lactobacillus coryniformis dominated SD 37. The isolated LAB were further used as starter cultures for the production of Oat sourdoughs. Fundamental rheology revealed softening of the sourdoughs compared to non-acidified and chemically acidified controls, which could not be attributed to proteolytic activity. Incorporation of Oat sourdough into an Oat Bread recipe resulted in significantly increased loaf-specific volume as well as improved texture, independent of addition level or sourdough type. Overall, the results of this study show that sourdoughs containing lactic acid bacteria isolated from Oats have the potential to enhance Oat Bread quality. © Springer-Verlag 2010.
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Oxidative and proteolytic enzyme preparations as promising improvers for Oat Bread formulations: Rheological, biochemical and microstructural background
Food Chemistry, 2010Co-Authors: Stefano Renzetti, Christophe M Courtin, Jan A. Delcour, Elke Karin ArendtAbstract:Commercial preparations of laccase (LAC) and glucose oxidase (GO) (0.01% and 0.1% addition levels), as well as of a protease (PR) (0.001% and 0.01% addition levels) were tested for their impact on the Breadmaking performance of gluten-free Oat flour. LAC 0.1%, PR 0.001% and PR 0.01% additions significantly improved Oat Bread quality, as they increased specific volume and decreased crumb hardness and chewiness. In contrast, GO 0.1% addition revealed detrimental effects, as it resulted in the hardest Bread crumb. The improved Breadmaking performances of Oat Breads with LAC and PR addition was explained by the increase in batter softness, deformability and elasticity which were achieved upon addition of these enzyme preparations, both containing discernible levels of endo-??-glucanase side activity. With LAC, the effect is due to prevalence of ??-glucan depolymerisation over protein polymerisation while, with PR, it is due to the combined effect of protein and ??-glucan degradation. Extensive protein hydrolysis during baking may have increased functionality of the soluble protein fraction. In contrast, extensive protein polymerisation was detrimental, as indicated by GO addition. ?? 2009 Elsevier Ltd. All rights reserved.
