Evaluation of antioxidant, rheological and sensorial properties of wheat flour dough and bread containing ginger powder

The effects of addition of ginger powder (0, 3, 4.5 and 6%) in formulation were examined in order to obtain an antioxidant-enriched bread with good physico chemical and sensorial properties. The rheological properties of doughs were evaluated using dynamic rheological measurements. Physical properties, total phenolics content (TPC- Folin-Ciocalteau method), radical scavenging activity (RSA- DPPH assay) and sensory analysis (hedonic test) of the supplemented bread were determined.The highest TPC (0.48 and 0.71 mg GAE/g DW on crumb and crust respectively) and RSA activity (0.15 and 0.24 μmol DPPH/mg DW ml⁻¹ on crumb and crust respectively) were achieved in the bread having the highest percentage of ginger powder (6%). But this sample showed the worst results regarding the rheological properties indicating that the dough and the bread had a tough structure. Moreover, by sensory evaluation this bread sample was not acceptable.Among the studied samples, bread with 3% of ginger powder showed good rheological characteristics and doubled anti-oxidant content compared to the control bread and the highest sensorial acceptability.     

Sourdough on quinoa and buckwheat gluten-free breads: Evaluation of autochthonous starter fermentation on bread nutritional and technological properties

The aim of this work was to evaluate the effect of two autochthonous strains of lactic acid bacteria as sourdough (SD) starters on gluten-free bread technological quality and in vitro starch hydrolysis and antioxidant activity. Two strains of Limosilactobacillus fermentum isolated from buckwheat (BW) and quinoa flours were used. SDs were prepared from wholegrain quinoa or BW flours. Bread technological properties, total polyphenol content and in vitro antioxidant activity and starch hydrolysis and dialysability were assessed. Specific bread volumes were between 2.61 and 2.76 cm³ g⁻¹. Breads with quinoa-based SD had overall higher technological quality than breads made with BW SDs, shown by a softer, well-aerated crumb, with an opener crumb structure and larger air area. Crumb firming during storage was reduced up to 29% when quinoa SD was used, and up to 42% when BW SD was added. Quinoa breads showed higher polyphenols and FRAP values, whereas BW breads had significantly higher ABTS values. Total starch hydrolysis and dialysability were significantly reduced when SD was used. Starch hydrolysis was reduced up to 42% and 25% when quinoa and BW SD were used, respectively. SD application produced breads with higher technological quality and modified in vitro starch hydrolysis and antioxidant capacity. Even though these effects seemed to be influenced by pH, a biological effect was also observed.     

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.     

Utilization of chestnut flour in gluten-free bread formulations

In this study, gluten-free bread formulations using chestnut and rice flours at different ratios (0/100, 10/90, 20/80, 30/70, 40/60, 50/50 and 100/0) were tested. In addition, the influence of hydrocolloid blend (xanthan-locustbean gum (LBG), xanthan-guar gum blend) and emulsifier DATEM on the rheological properties of dough formulations and quality parameters of breads were also investigated for the samples having chestnut/rice flour ratio of 10/90, 20/80, 30/70 and 40/60. Herschel-Bulkley model was found to explain the flow behavior of all dough formulations. The power-law index (n) of dough samples at 25 °C ranged from 0.52 to 0.87, the consistency index (K) of the samples ranged from 3.6 to 79 Pa sⁿ and the yield stress of the samples ranged from 4.8 to 85.9 Pa. The breads prepared with chestnut/rice flour ratio of 30/70 and containing xanthan-guar blend and emulsifier, had higher quality in terms of hardness, specific volume, color and sensory values. However, elevated levels of chestnut flour led to some deterioration in quality parameters (low volume, harder texture and darker color) regardless of gum blend and emulsifier addition.     

黑小麦全粉的流变学特性及复配混粉馒头的品质研究

通过对黑小麦全粉、与对照样特精粉复配混粉的面筋数量与质量测定,对黑小麦全粉占10%、15%、20%、25%、30%、40%、50%复配混粉进行流变学特性指标的测定及制作馒头成品以评价。结果表明:不同复配比例的混粉湿面筋数量表现比例越大含量越高;黑小麦全粉的流变学特性较差;复配混粉也都低于对照样特精粉的流变学指标;黑小麦全粉单独并不适合制作馒头,当复配比例在10%~15%时,馒头评价总分在80以上。     

Effect of phenolic acids on the rheological properties and proteins of hard wheat flour dough and bread

BACKGROUND: The effects of different phenolic acids on the rheological properties and gluten proteins of hard wheat flour dough and bread were investigated. Caffeic, ferulic, syringic and gallic acids were each blended with hard wheat flour at a concentration of 4.44 µmol L^?1 g^?1 flour. RESULTS: Mixing time and tolerance were reduced with the addition of phenolic acids. The phenolic acids reduced the maximum resistance to extension (R_max) and increased the extensibility of dough, with effects in the following order: gallic < syringic < ferulic < caffeic acid. The effect on R_max was more pronounced in overmixed dough. Loaf volume was most significantly decreased with the addition of caffeic acid. Extraction of sodium dodecyl sulfate‐soluble high‐molecular‐weight proteins was increased in both mixed and fermented doughs by the addition of ferulic and caffeic acids. The order of influence of the phenolic acids on the rheological properties and protein structure of dough and bread was consistent with that of their antioxidant activity. CONCLUSION: The addition of caffeic and ferulic acids reduced R_max and increased the extensibility of hard wheat flour dough by modifying the high‐molecular‐weight gluten, which resulted in decreased bread volume. Copyright © 2011 Society of Chemical Industry     

Thermal and dynamic rheological properties of wheat flour fractions

A commercial high gluten flour (HGF) was fractionated into prime starch (PS), tailing starch (TS), and gluten (G). Fractions were examined alone or in various combinations. Dynamic rheological properties of samples were measured in an oscillatory rheometer (strain 0.02; frequency 0.1 Hz) during heating at 1°C/min. Thermal characteristics of samples were determined by differential scanning calorimetry (DSC) at a heating rate of 10°C/min. The loss (G″) and storage (G′) moduli of PS and mixed G/PS, G/TS, and G/PS/TS increased after 60°C, reaching peak values (e.g. 81, 301, 313, and 3000 Pa in G′, respectively) around 75°C after which the moduli decreased. HGF showed a steady increase in G′ from 32 to 2490 Pa as temperature increased from 65 to 90°C, indicating continuous formation of elastic networks. Cooling increased G′ for G/PS/TS, decreased G′ for HGF, and produced no rheological transitions for all samples. TS and G alone did not exhibit appreciable viscoelastic responses to the heating and cooling temperatures. DSC measurements revealed a major endothermic transition in HGF. This transition, with a peak around 60°C, was due to starch gelatinization. The presence of G or TS resulted in reduced melting enthalpies of starch in the PS fraction. Gluten or TS fractions alone or in combination did not exhibit any endothermic transitions.     

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.     

配麦和配粉对小麦粉面团流变学特性的影响

选用7种高、中、低筋小麦,对其品质进行综合分析;根据分析结果以水饺粉为目标粉进行配麦和配粉实验,对混合粉的流变学特性进行分析研究。结果表明差异性大的小麦(粉)以合适的比例搭配能明显改善混配粉的流变学特性。配麦和配粉在提高稳定时间,降低弱化度,改善拉伸特性方面区别并不明显,但在降低吸水率和拉伸度方面配粉比配麦表现效果更加明显。     

Effects of freezing and frozen storage conditions on the rheological properties of different formulations of non-yeasted wheat and gluten-free bread dough

Empirical and fundamental rheological measurements were made on fresh and frozen dough to study the effects of freezing and frozen storage conditions. Frozen dough was stored at two different temperatures, −18 °C and −30 °C, and for 1, 7 and 28 days. Four dough formulations were tested: a standard wheat dough, a fibre-enriched wheat dough, a standard gluten-free dough and a gluten-free dough containing amaranth flour. No yeast was used in any formulation. The wheat dough is more affected by freezing and by the first days of storage whereas the gluten-free dough is more affected by a longer storage time. A storage temperature of −30 °C alters dough rheological properties more than a storage temperature of −18 °C. The addition of dietary fibres to the wheat dough increases its resistance to freezing and frozen storage. The addition of amaranth flour to gluten-free dough also increases its resistance to freezing but decreases its resistance to storage conditions.     

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.     

小麦粉面筋蛋白质流变学特性的研究

本试验采用快速黏度仪(RVA)通过面筋蛋白醇溶指数法,研究了不同类型小麦粉的面筋蛋白醇溶指数,探讨了不同小麦粉的粉质特性、拉伸特性及湿面筋、面筋指数及其与醇溶指数、最终黏度的影响.结果表明:不同类型的小麦粉的面筋蛋白RVA曲线存在明显差异,醇溶指数在α=0.05水平上与小麦粉吸水率、延伸性呈负相关,与峰值黏度呈正相关;在α=0.10水平上与小麦粉稳定时间呈负相关,最终黏度在α=0.05水平上与小麦粉面筋指数呈负相关,与峰值黏度呈正相关.因此,麦胶蛋白明显影响小麦粉的吸水率、稳定时间、延伸性及面团的面筋指数,而与拉伸阻力、湿面筋及弱化度无相关性,此与麦胶蛋白的富有延伸性、粘性,但弹性小的性质有关.     

Synergism between lipoxygenase‐active soybean flour and ascorbic acid on rheological and sensory properties of wheat bread

BACKGROUND: The interaction between lipoxygenase‐active soybean flour (LOX) and ascorbic acid (AA), on colour, rheological and sensory properties of wheat bread was studied with the aim of reducing the applied quantity of additives in bread formulations. RESULTS: The ascorbic acid (0–500 ppm) and active soybean flour (0–1%) mixture improved bread‐crumb colour by lowering the yellow hue in a higher proportion than those expressed by the components alone, characterising a synergistic mechanism (?_b = 15.1? (1.7 × LOX) ? (0.5 × AA) ? (5.8 × LOX × AA), where ?_b represent the estimated value for the yellow hue parameter). No differences in flavour and porosity were seen between the samples. As supported by the instrumental methods, breads made with active soybean flour and ascorbic acid (LOX + AA) had whiter crumbs and were softer and springier than controls as assessed by a trained sensory panel. In summary, the combination of both active soybean flour and ascorbic acid showed synergism, promoting a greater bleaching effect than when used alone. CONCLUSION: These results suggest the potential use of active soybean flour as a synergistic ingredient in the substitution of artificial additives in bread making. Since the interaction on the bleaching response was not linear and active soybean flour showed a higher iron concentration (66.40 ± 4.23 µg g^?1) than non‐active soybean flour (52.30 ± 0.40 µg g^?1), more studies are warranted to establish the biochemical mechanisms involved in this interaction. Copyright © 2007 Society of Chemical Industry     

Improving the sensory and nutritional value of gluten-free bread

Bakery products, especially breads, are important part of everyday diet. Home-made breads are all the more crucial on the gluten-free diet, as commercially available breads without gluten are often unattractive. The study presents the recipe, nutritional characteristics (fat, protein, calcium, magnesium, sodium, potassium, copper, iron, zinc, manganese), costs and consumer acceptance of four easy to make home-made gluten-free breads. Partial substitution of bread-mix based on corn and rice (control bread) with teff flour, amaranth flour or quinoa flour significantly changed the content of the most of analysed nutrients, while their price was comparable. The highest nutritional benefits were found for protein, magnesium, potassium, calcium, zinc, iron and manganese in bread with teff and for magnesium, potassium, zinc and manganese in bread with amaranth. The highest consumer acceptance of people on gluten-free diet was noticed for breads with quinoa and teff.