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1.
This study demonstrates new possibilities in using freeze‐dried buckwheat sourdoughs in the processing of gluten‐free bread (GFB). Fresh and freeze‐dried (at temperatures of 20, 40 and 60 °C) sourdoughs were added in the amounts of 10, 20, 30 and 40% of the total flour content. Significant and beneficial changes in the quality of bread under the influence of different quantities of fresh and freeze‐dried sourdoughs additive were observed. Freeze‐dried buckwheat sourdoughs at the level of 20 and 30% gave the best baking results for GFB. pH of bread significantly changed, which had a positive effect on increasing its suitability for the storage. Buckwheat sourdough dried at 40 °C is the most highly recommended for GFB processing. Higher temperatures (60 °C) caused the least change in bread volume; however, a bitter aftertaste from burning was slightly detectable. Freeze‐dried buckwheat sourdoughs can be used directly in processing, thus eliminating the long fermentation of sourdough.  相似文献   

2.
The objectives of this study were to assess the effect of the addition of different hydrocolloids on gluten‐free batter properties and bread quality and to obtain information about the relationship between dough consistency and bread quality. Breads were made of rice, corn and soy flours and 158% water. Following hydrocolloids were added: carrageenan (C), alginate (Al), xanthan gum (XG), carboxymethylcellulose (CMC) and gelatine (Gel). Batter consistency, bread specific volume (SV), crumb analysis, crust colour, crumb hardness and staling rate were determined. Hydrocolloids increased batter consistencies: the highest value was obtained with XG, which doubled that of control batter, followed by CMC. Breads with hydrocolloid presented higher SV than control, especially with XG whose SV was 18.3% higher than that of control bread. A positive correlation was found between SV and batter consistency (r = 0.94; P < 0.05). Crumbs with Gel, XG and CMC presented higher cell average size. XG and CMC crumbs looked spongier. Breads containing hydrocolloid evidenced lighter crusts. Crumb firmness was decreased by XG and CMC addition, and staling rate was slower. Overall, XG was the hydrocolloid that most improved gluten‐free bread quality. These results show that, in formulations with high water content, batter consistency is strongly associated with bread volume.  相似文献   

3.
Green plantain flour (GPF) was used as a functional ingredient to produce gluten‐free (GF) bread based on a flour blend of rice flour and GF wheat starch (50:50) to improve their functional properties and to increase their resistant starch (RS) content. In pretrials, an addition of up to 30% GPF provided acceptable bread quality with maximum RS content. Based on these trials, two 23 factorial screening experimental designs were applied, where water content, baking temperature and baking time of GF bread containing 30% GPF addition were optimised. The best baking conditions to achieve satisfying GF bread quality – higher loaf volume, softer crumb firmness and regular porosity structure at the highest RS content could be defined to a maximum addition of water at 160%, baking temperature of 180 °C and baking time of 90 min. The incorporation of GPF showed good potential to improve the quality of GF bread.  相似文献   

4.
The effect of soybean flour on gluten‐free bread quality was studied. Full‐fat enzyme‐active, semiactive and inactive soybean flours were evaluated. Active soybean flour improved the volume and structure of gluten‐free bread, while semiactive and inactive soybean flours did not have positive effects on bread quality. The particle size and concentration of the soybean flours also affected bread quality. Levels of addition between 125 and 150 g kg?1 and particle sizes between 90 and 120 µm of active soybean flour yielded the best results. Heating the active soybean flour destroyed its improving effect. The analysis of proteins by sodium dodecyl sulphate polyacrylamide gel electrophoresis and size exclusion chromatography showed that heating soybean flour at 60–200°C caused protein aggregation. The overall results indicated that the addition of active soybean flour improved gluten‐free bread quality, and this effect seemed to be due to both the structural proteins and the enzymatic activities of the soybean flour. Copyright © 2004 Society of Chemical Industry  相似文献   

5.
The purpose of this study was to evaluate the effect of the addition of pomegranate seed powder (PSP) on physical, sensorial and antioxidant properties of gluten‐free bread. The PSP was incorporated at different levels (2.5%, 5.0%, 7.5% and 10%) into formula of gluten‐free bread. Control gluten‐free bread made without any addition of PSP was used for comparison. The results showed that the specific volume and springiness of gluten‐free breads increased, whereas hardness and chewiness decreased significantly with increasing PSP addition. The addition of PSP into gluten‐free bread decreased the lightness and yellowness of crumb and crust colour, while redness increased. Total phenolics content (TPC) increased from 46% to 181% with PSP addition (2.5%–10%). Moreover, antioxidant activity was significantly higher for bread with PSP. For bread with the highest percentage of PSP, the highest antioxidant activity was obtained. For sensorial and antioxidant activity, the optimum level of PSP addition was found to be 7.5%.  相似文献   

6.
Gluten‐free (GF) sourdough was prepared from wheat sourdough and analysed both in fresh (GFS) and dried forms (DGFS). The gluten content in each GF sourdough sample was <20 mg kg?1. The dough leavening capacity and the properties of the bread samples were investigated and compared to those of bread prepared using bakery yeast (Saccharomyces cerevisiae). Two commercial rice‐based mixtures (different for the presence/absence of buckwheat flour) were used to prepare bread samples. In GFS, lactic acid bacteria (LAB) and yeasts were found in amounts corresponding to 108 and 107 CFU g?1, respectively, whereas both LAB and yeasts were detected in lower amounts (about 106 CFU g?1) in DGFS. When used in bread‐making, both GFS types produced significant dough acidification and exhibited good dough development during proofing, resulting in loaves with specific volume values between 3.00 and 4.12 mL g?1, values similar to those obtained for reference bread (3.05÷4.15 mL g?1). The use of GFS was effective in lowering the bread staling rate during storage for up to 7 days.  相似文献   

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9.
This study aimed to investigate effect of butter content (0–30 g/100 g flour) and baking conditions hot air baking (HA), microwave baking (MW) and hot air‐microwave baking (HA‐MW) on quality of the rice flour dough and bread. The increased butter (up to 15 g butter/100 g flour) enhanced elastic modulus (G′) and viscous modulus (G″) of dough and specific volume of bread. Additionally, the increased butter improved crust colour and reduced hardness of the bread. The HA‐MW and MW conditions were useful for the gluten‐free bread by reducing baking time and predicted glycemic index (GI), regardless of butter content. However, enthalpy of retrogradation and crystallinity in the HA‐MW and MW bread stored at 4 °C for 7 days were increased and higher than those of the HA bread, indicating a faster staling. The predicted GI of both MW and HA‐MW bread remained at a medium level during storage.  相似文献   

10.
The influence of zein protein and hydroxypropyl methylcellulose (HPMC) on the texture and volume of gluten‐free bread was investigated. The addition of HPMC to starch affected the dough viscoelasticity and it improved the bread volume during baking since it acts as an emulsifier. The addition of zein protein to gluten‐free bread increased the crumb firmness and reduced the crust hardness within the range of concentrations investigated. No zein protein network could be observed in the bread crumb. The zein protein, cold mixed at low concentration, did not enhance the dough elasticity. Due to the lack of a protein network noncovalent interactions may stabilize the bubble structure stabilization within the crumb, rather than covalent links of the protein chain. With an optimized amount of zein protein and HPMC hydrocolloid, the gluten‐free bread showed similar texture and staling behavior to that of model wheat bread. The optimized recipe, compiled into a spreadsheet, is available in the supporting information. The microstructural observations suggest that zein could be replaced with another protein for this recipe resulting in a similar bread texture.  相似文献   

11.
The effect of three different rice varieties with different starch shapes (Seolgaeng (SG), round starch structure; Samkwang (SK), polygonal starch structure and Boramchan (BRC), polygonal starch structure) on rice flour characteristics and gluten‐free bread baking quality was investigated. Rice flours were produced by dry milling and passed through a 200 mesh sieve. Electron microscopy revealed that the structure of SG grains, with round starch granules, possessed larger void spaces than SK and BRC, composed of polygonal starch granules. For this reason, SG grain had low grain hardness and consequently, it was milled to a fine flour with low damaged starch content. The thermo‐mechanical properties were determined by Mixolab, which revealed that SG was gelatinised rapidly and maintained high viscosity after gelatinisation. These characteristics gave SG flour the ability to build up bread structure without gluten. Specific volume and crumb hardness of gluten‐free rice breads made of SG, SK and BRC flours were 3.37, 3.11 and 2.12 mL g?1 and 2.61, 2.76 and 6.46 N, respectively. The SG flour with round starch structure is appropriate for making gluten‐free rice breads.  相似文献   

12.
The chemical modification of rice flour by phosphorylation is an alternative to improve the technological quality of bakery products. The aim of this study was to investigate the effect of phosphorylation process of rice flour on technological properties (specific volume, crumb and crust colour) of gluten‐free breads and the hardening of these breads during two storage temperatures (21 °C and ?24 °C). Breads were made with native rice flour, with phosphorylated rice flour and with wheat flour, used as control. The phosphorylation causes significant reduction in the synaeresis of pastes and in retrogradation tendency of rice flours, varying from 258.7 cP (native rice flour) to 122 cP (phosphorylated rice flour). The breads prepared with phosphorylated rice flour showed reduction in the hardness in both storage temperatures studied and effect on rice bread volume, crumb appearance and colour, demonstrating the possibility of use of the phosphorylated rice flour in gluten‐free breads.  相似文献   

13.
The aim of this work was to analyse the influence of defatted almond flour on soya bean‐based gluten‐free pasta. Optimal cooking time of pasta varied between 2.0 and 3.5 min, while cooking loss ranged 6.1% and 19.7%. The total protein content of samples varied from 30.4% to 41.0% (dry basis, db) in cooked pasta. The total phenols content of cooked samples varied between 1.66 and 2.99 mg ellagic acid equivalent/g, while the antioxidant activity (DPPH?) ranged between 19.1% and 41.9%. The sensory test showed no significant differences between the formulated pasta samples among brightness (3.20–3.27), surface appearance (1.14–1.20), hardness (2.14–2.36) and elasticity (1.56–1.71). Pasta developed is an innovative product that improves nutritional and functional properties of gluten‐free pasta compared to gluten‐free and traditional wheat flour pasta available on market.  相似文献   

14.
Maize is used for bakery and for gluten‐free food for coeliac patients. Our objective was assessing diversity for dough rheology and breadmaking in maize with different origins, grain types and growth cycles. Endosperm type affected bread crumb colour having dent maize higher L* and a* and instant recovery speed. Population origin affected flotation index, onset pasting temperature, bread crumb colour, hardness and instant recovery speed. Finally, growth cycle affected flotation index, crumb colour L* and a* and cohesiveness. Water‐binding capacity, crumb colour and hardness were the most discriminative parameters for maize. The maize population Andaluz/Daxa was the less distant from wheat parameters, and Tremesino was the most different.  相似文献   

15.
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.  相似文献   

16.
Chickpea flour (CF)‐based muffin formulations were made with CF alone and with added biopolymers [whey protein (WP), xanthan gum (XG) and inulin (INL)] to evaluate their suitability to be a wheat flour (WF) substitute in muffins. Structural characteristics of the batters and muffins were studied by means of rheometry, microscopy, physicochemical properties, and texture and sensory analysis. Partial replacement of CF with XG, alone (at 0.5 and 1%) or blended with either WP or INL, significantly increased the batter viscoelasticity as denser matrices developed; moreover, the muffins with XG added at 1% had similar hardness to wheat gluten muffins. The replacement of WF decreased the springiness, cohesiveness, chewiness, resilience and specific volume of the muffin. However, baked muffins with added XG also showed higher sensory sponginess and moisture associated with numerous air bubbles in the batter and were perceived to be easier to swallow and to have better general appearance.  相似文献   

17.
Canola proteins extracted by electroactivated solutions were incorporated to gluten‐free biscuits made from blend of rice and buckwheat flours. Physical and textural properties were significantly influenced by these proteins. Isolates and concentrates did not behave in a similar way. A significant increase in diameter was noted for all of the supplemented samples. An increase in thickness was observed for the samples added with protein concentrate, whereas the spread ratio decreased for all the samples compared to control. The hardness of biscuits decreased with the addition of the proteins as compared to the control. The changes in biscuit hardness or fracture strength were in line with the changes in dough hardness. Biscuits containing protein concentrate had lighter, more aerated texture as shown by scanning electron microscopy with lesser amounts of gelatinised starch, indicating improved gas‐holding capacity and more stabilised structure. Protein‐supplemented biscuits have lower moisture and water activity.  相似文献   

18.
In the present study new formulations for gluten-free bread based on mixtures of rice (RF) and buckwheat flour (light buckwheat flour (LBF) or wholegrain flour (WBF)), in the proportions of 90:10, 80:20, and 70:30 were made. The gluten-free breads were investigated for their total phenolic content, rutin and quercetin contents, antioxidant activity (AOA) by β-carotene bleaching method, reducing power, scavenging activity on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, and chelating activity on Fe2+. The increased amount of LBF or WBF in the dough formulation resulted in the final products with higher antioxidant properties. Baking treatment expressed different influences on antioxidative properties of the final gluten-free product in terms of raw materials, applied recipe and antioxidative capacity in comparison to calculated values based on raw materials. Final gluten-free products were characterized by lower total phenolic and rutin contents, lower antioxidative and reducing activity and on the other hand higher DPPH and chelating activity as well as quercetin content in comparison to calculated values. Bread containing wholegrain buckwheat flour expressed in most of the cases higher values of measured antioxidative parameters than bread prepared with light buckwheat flour and thus contributes to their additional functional property.  相似文献   

19.
The effect of egg white, skim milk powder, soy protein isolate and soy protein concentrate on creep‐recovery parameters of gluten‐free batter made from sorghum and pregelatinised cassava starch was studied. Batter treated with egg white had the highest deformation and compliance parameters and lowest zero shear viscosities and differed significantly (P < 0.05) from the other treatments. However, this batter recovered its elasticity sufficiently and its elastic portion of maximum creep compliance did not differ significantly (P < 0.05) from the other treatments. Unlike the other treatments, egg white did not decrease bread volume and exhibited the lowest crumb firmness and staling rate. Optimisation of the amount of egg white with diacetyl tartaric acid esters of mono and diglycerides (DATEM) showed that creep‐recovery parameters and crumb hardness were affected by the linear, quadratic and interaction effects of the input variables. Treatment with 6% and 0.1% w/w fwb egg white and DATEM, respectively, gave gluten‐free batter with the least elastic portion of maximum creep compliance (Je/Jmax = 11.65%) which corresponded to the lowest crumb firmness (790.8 g).  相似文献   

20.
In recent years, gluten‐free (GF) goods have become popular, fuelling a growing market, as they not only cater to individuals with medical needs but also to consumers who seek a GF diet. In their development, it is pivotal to pay attention to nutritional quality. This review aims to provide some insights on the nutritional quality of GF products, focusing on major concerns and the strategies to overcome them. In order to mimic the viscoelastic properties of gluten, a large number of flours and starches and other ingredients have been used. Therefore the different mixtures of these ingredients bring a wide difference in the nutritional composition of GF foods with respect to gluten‐containing counterparts. Several GF foodstuffs contain more fat, including saturated, and salt but fewer minerals and vitamins than their equivalents with gluten. The increased fibre content and improved technological processes have positively affected the glycaemic responses from these goods. However, in order to improve their nutritional quality, wholemeal GF cereals and pseudocereals with high nutritive value should replace the low‐nutritional GF flours and consequently the technological processes would be optimized. The improvement of the nutritional quality of GF products, and in turn that of the GF diet, should also be aimed at lowering the risk of later chronic degenerative disorders, especially for infants and young children. © 2015 Society of Chemical Industry  相似文献   

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