Impact of quinoa bran on gluten-free dough and bread characteristics

Besides an appealing texture and taste, gluten-free products should feature a well-balanced nutrient profile, since celiac disease or chronic inflammations are likely to induce malnutrition for involved patients. Due to their composition, pseudocereals represent a promising ingredient to improve nutrient profile of gluten-free bread. The objective of this study was to investigate the impact of quinoa bran on gluten-free bread quality, focusing on volume, pore size and sensory acceptance. The impact of quinoa bran was studied in a gluten-free bread formulation. Five different quinoa bran and two whole grain flour concentrations were evaluated and compared to a control formulation based on rice and corn flour. The rheological properties of quinoa bran as well as the effect on dough development up to a replacement level of 80 % were investigated. Baking tests were carried out, and loaf volume, crumb firmness and sensory characteristics were determined. Quinoa fractions significantly increased carbon dioxide formation (p < 0.05) due to a higher substrate availability. Gas retention was reduced by increasing bran levels (p < 0.05). Oscillation measurements indicated a firming impact of quinoa bran which might have caused a more permeable dough structure, promoting the release of carbon dioxide. With regard to the specific loaf volume significant differences were found across the quinoa milling fractions and the applied levels (p < 0.05). Overall this study demonstrated that 10 % bran improved the bread volume by 7.4 % and enhanced the appearance without compromising the taste.     

Influence of inulin on physical characteristics and staling rate of gluten-free bread

Inulin preparations with different degree of polymerization (HSI with a DP < 10, GR − DP ? 10 and HPX − DP > 23) were used for the production of gluten-free bread. It was found that an addition of investigated compounds resulted in an increase of loaf volume and reduction of crumb hardness. However, internal structure of the obtained loaves was less uniform and more open than in control bread. Generally, inulin preparations with lower degree of polymerization had stronger effect on all analyzed parameters than that with higher DP. A decrease in staling was observed (measured as the rate of crumb hardening), which was caused by the presence of inulin. The highest content of retrograded amylopectin was found for crumb with HSI, and the lowest for samples with HPX.     

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.     

The effects of maltodextrins on gluten-free dough and quality of bread

The aim of the study was to check if maltodextrins of various dextrose equivalents (DE) could be used to improve stability and quality of gluten-free bakery products, and effectively reduce starch retrogradation. The maltodextrins, which were used for partial replacement of starch in the recipe for gluten-free dough, were characterised by DE 3.6, 15.3, 18.0 and 21.8. Basing on the obtained results it was concluded, that the addition of applied maltodextrins significantly influences starch gelatinisation, by increasing pasting temperature and reducing viscosity of the obtained pastes. Rheological properties of the obtained dough are also modified by maltodextrins, which weaken its structure and increase deformation sensitivity. The addition of maltodextrins with low DE (3.6) diminishes loaf volume and causes deterioration of bread quality. Maltodextrins with higher DE, especially 18.0 and 21.8, positively influence bread volume and have a beneficial influence on crumb hardening during storage. Maltodextrin with the highest DE is also an effective factor reducing recrystallisation enthalpy of amylopectin.     

The effect of emulsifiers,sugar, shortening and soya flour on the staling of barbari flat bread

A standard method has been developed to bake barbari flat-type bread. Instron was used to measure the hardness of the crumb of bread samples as a criterion of staling. Different combinations of emulsifiers, sugar, shortening and soya flour were added to the formula of barbari bread to find their effect on the retardation of hardness. Addition of soya flour increased the loaf weight but decreased its total organoleptic score. Added amounts of different additives tried in this experiment improved the hardness approximately to the same level. The best result was obtained by the addition of sodium stearoyl-2-lactylate and shortening.     

Effect of quinoa,chia and millet addition on consumer acceptability of gluten-free bread

There is an increasing demand for gluten-free foods; however, standard gluten-free foods are deficient in nutrients. This study investigated the use of alternative grains (chia, millet and quinoa) in gluten-free breads to evaluate their sensory properties (fresh and following a partial bake method). A sensory trial (n = 98) asked participants to consider six fresh bread samples made from chia, millet and quinoa, using 9-point hedonic scales and check-all-that-apply. A second sensory trial (n = 89) was then completed using par-baked bread samples of the different formulations. The sensory properties and the acceptability of the bread were significantly affected by the chia and quinoa flour. The millet flour did not change the acceptability of the bread. Furthermore, the partial baking method (after 90 days of frozen storage) did not significantly affect the acceptability of the breads made with chia, millet and quinoa, but it did affect the acceptability of the control bread prepared with brown rice flour. Overall, millet flour could be incorporated into gluten-free breads made following a partial baking method without affecting consumer acceptability. Future studies should use a trained panel to evaluate how the breads differ based on the partial baking method.     

Influence of modified starches on properties of gluten-free dough and bread. Part II: Quality and staling of gluten-free bread

The aim of the study was to check the quality of gluten-free bread produced basing on the recipes, in which part of native starch was replaced with high amylose corn starch (HACS), acetylated distarch adipate (ADA), and hydroxypropyl distarch phosphate (HDP). The application 10 or 15% of chemically modified starches (HDP, ADA) caused the increase in volume of the obtained gluten-free loaves. The changes were accompanied by a decrease of average cell size, and an increase in their number. Due to the addition of modified starch crumb structure became more elastic, which was revealed in the results of stress relaxation. A slight decrease in hardness and chewiness of the crumb was also observed on the day of baking, and its extent depended on the level of modified starch, and was a little more pronounced in case of starch adipate. In comparison to the chemically modified starches, HACS deteriorated structural and mechanical properties of the crumb, which is probably related to their resistance to pasting and divergence in retrogradation pattern, where amylose component is more important than amylopectin.     

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.     

The role of buckwheat and HPMC on the breadmaking properties of some commercial gluten-free bread mixtures

Although the food industry has risen to the formulation challenges associated with removing gluten from dough, and a number of gluten-free (GF) products are now commercially available, many GF bread formulations are still based on pure starches, resulting in low technological and nutritional quality. The aim of this research was to evaluate the role of buckwheat and HPMC on the breadmaking properties of two commercial GF bread mixtures. A dehulled (DBF) and a puffed (PBF) buckwheat flour were used, and high substitution levels (40%) were tested, with the aim of improving the nutritional value of the final GF breads without decreasing their technological quality. Ten mixtures (2 commercial, 8 experimental) were evaluated. The inclusion of 40% DBF was demonstrated not to reduce but actually improve the baking performances of the commercial GF mixtures. Moreover, the presence of a small amount of PBF, as well as of HPMC, turned out to be useful in limiting both the diffusion and the loss of water from the bread crumb and the interactions between starch and protein macromolecules, resulting in a softer GF bread crumb and reduced staling kinetics during storage.     

Influence of unicellular protein on gluten-free bread characteristics

The objective of this work was to study the characteristics of three gluten-free bread formulations and the effect of the inclusion of unicellular protein. Bread recipes were starch-based, starch-vegetable-based and flour-based and the same recipes with added unicellular protein. Flour-based breads had lower specific volume values (2.2–2.3 cm³/g) than starch-based breads (3.1–3.3 cm³/g). Starch-based and starch-vegetable-based formulations with unicellular protein showed less bake loss (18.3 and 17.8%) than their counterparts (21.1 and 19.6%) probably due to increased water retention caused by unicellular protein. Flour-based recipes resulted in the firmest crumb, mainly caused by the high content in dietary fiber. The addition of unicellular protein resulted in a darker crumb color, and significant differences were also found in crumb color because of ovalbumin addition. Confocal scanning laser microscopy results showed a more compact microstructure in flour-based recipes compared with starch-based and starch-vegetable-based formulations. Starch-vegetable-based formulations without unicellular protein were the most preferred by consumers, followed by starch-vegetable-based formulations with added protein. Main differences detected by consumers were related to texture attributes. No major changes in shelf-life could be attributed to differences in formulation.     

Effect of water,albumen and fat on the quality of gluten‐free bread containing amaranth

The aim of the research was the development of an alternative formula for gluten‐free bread (GFB) containing amaranth flour. GFBs were prepared using a 2³ factorial screening experimental design. The amount of water, albumen and fat varied in order to evaluate their impact on the textural, structural and sensory characteristics of the final product. Water amount had the greatest influence on bread characteristics. For a 33% water content increase (from 0.6 to 0.8 g g^?1 of flour) the firmness of the crumb decreased to 20% of the initial value. Also, for the same water content increase, the average pore size became 2.5‐fold greater. Albumen addition (from 0 to 0.04 g g^?1 of flour) influenced mainly crumb viscoelasticity (20% increase). Variations in fat amount did not significantly influence any of the response variables investigated. However, the combined addition of fat and albumen resulted in breads that received the best rankings in overall acceptance in sensory evaluation.     

苦荞面包的研制及品质评价

通过响应面分析法确定苦荞面包研制的最佳条件,即苦荞粉添加量12.6%,和面时间33.9 min,发酵时间2.2 h,烘烤时间19.6 min。通过质构仪测定苦荞面包品质,总体来看,苦荞面包品质较好。     

The impact of resistant starch on characteristics of gluten-free dough and bread

The study focused on partial replacement in gluten-free breads of corn starch with tapioca and corn resistant starch preparations. The use of resistant starch resulted in the increase of storage and loss moduli of the dough, and the lowering of loss tangent, which indicates its more elastic character. The incorporation of resistant starch reduced creep and recovery compliance and elevated zero shear viscosity. Modified doughs displayed higher starch gelatinization temperatures and lower viscosities that were proportional to the share of RS. It was found that the loaves baked with the share of resistant starch had less hard crumb than bread without RS addition. The crumb hardness diminished with the increasing amount of applied RS preparation. The addition of resistant starch raised total dietary fibre, by up to 89%, as compared to control (bread without RS addition). The most pronounced change was observed for insoluble dietary fibre (increase 137%), while only slight increase was found for its soluble fraction (18%).     

荞麦粉对馒头品质的影响

荞麦具有丰富的营养和药食价值,采用10％、20％、30％、40％、50％和60％的全荞麦粉置换出等量高筋小麦粉蒸制馒头,通过荞麦馒头感官评价、色泽、质构特性的变化,研究荞麦粉对馒头品质的影响.结果表明:全荞麦粉会弱化面团结构,影响馒头的品质.随着荞麦粉添加量的增加,馒头表皮及内部色泽变暗,质构参数中硬度、胶凝性、咀嚼性明显增大.     

添加HPMC对无麸质大米面包品质的影响

水稻是全球主导的粮食作物之一,作为无麸质食品的主要原料倍受青睐。但水稻中缺乏面筋蛋白,在发酵过程中难以形成持气性较好的网孔结构,所以很难获得理想的面包类发酵产品。本论文探讨了采用HPMC为面筋替代物制作无麸质大米面包的可行性,并研究了HPMC对大米面包品质的影响,从而为无麸质大米面包的制作奠定基础,为大米资源的广泛应用开辟新的途径。结果表明,当添水量提高到100%110%时,4%的HPMC可以作为面筋替代物,用以改善大米面团的品质,烘焙出优质、理想的无麸质大米面包,但其淀粉体外消化率和整体感官评价却受到影响。最后认为,应该把无麸质大米面包看作为一类新型的焙烤食品,不一定要完全适用小麦面包的评价体系。     

荞麦粉对面团流变学特性和馒头品质的影响研究

通过对不同筛粉目数的荞麦粉色泽以及馒头感官的测定,确定最佳筛粉目数,并且将荞麦粉以不同比例添加到小麦粉中,研究其对面团流变学特性以及对馒头品质的影响。结果表明,100目的荞麦粉可以有效地保留荞麦小麦馒头中混合粉原有的色泽特征,在小麦粉中添加不同量的荞麦粉会影响面团的粉质特性和延展性,且荞麦粉的添加量不宜超过40%;通过对荞麦小麦馒头的感官评价和质构得出,荞麦粉的添加量为20%时馒头的色泽、外形、感官、质地最好。     

面粉特性对荞麦馒头预拌粉品质的影响

测定8种不同面粉的基本性质、面团流变特性、发酵特性,并用其制备成荞麦馒头预拌粉制作荞麦馒头,通过测定荞麦馒头的比容、质构特性、感官品质等指标,探究面粉特性对荞麦馒头预拌粉品质的影响。试验结果表明:湿面筋含量在33%～34%,蛋白质含量在11%～12%的面粉其蛋白质弱化度较小,面团形成时间和稳定时间较长,面团的持气率较好,面团开始漏气时间较晚;对应编号制作的荞麦馒头比容较大,硬度、弹性、咀嚼性适中,感官评价总分较高;灰分0.4g/100g的面粉制作的荞麦馒头表面颜色光亮、色泽均匀。综上可得:湿面筋含量在33%～34%,蛋白质含量在11%～12%,吸水率在58%～60%,灰分0.4g/100g的面粉制作的荞麦馒头品质较好,比较适合制备荞麦馒头预拌粉。