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1.
Whole wheat flour has been developed as fiber-rich food for healthy bowel function. In this study, whole waxy wheat flour (WWF) was characterized and applied for breadmaking with the hope that breads made from WWF would improve the quality based on the superior properties of the waxy flour in retardation of bread staling. WWF had significantly higher protein, ash and dietary fiber contents (13.5%, 1.6% and 15.3%, respectively), but lower lipid content (0.8%) than commercial white flour (CWF). Amounts of soluble and insoluble dietary fiber in WWF were 4.1% and 11.2% (% total weight), respectively. WWF had lower pasting temperature and viscosities than CWF. Dough made from WWF increased water absorption and showed lower stability during mixing than that from CWF. The high amount of dietary fiber diluted the gluten protein in dough during mixing to form weak and inextensible dough. Bread made from whole waxy wheat flour had significantly low specific volume and big gal cell distribution as compared to that from CWF. Also, dark-brown color and bitter taste are weak points of whole waxy wheat bread. However, the WWF bread was significantly softer than CWF bread during storage. The qualities of breads were also improved using partial WWF substitution (10%, 30% or 50%) for CWF. As a result, whole waxy wheat flour can be used for breadmaking to improve nutritious quality of bread for health benefits.  相似文献   

2.
Research has shown that prolonged frozen storage of bread dough reduces the quality of the end product. In this study, the effect of air‐classified barley flour fraction rich in β‐glucan (approximately 25%) on rheology and quality of frozen yeasted bread dough was investigated. Wheat flour (W) was replaced by air‐classified barley flour fraction (B) at 10% without or with 1.4% vital gluten to produce β‐glucan enriched barley dough (WB) or barley dough plus gluten (WB + G). Dough products were stored at ?18 ºC for 8 wk and their rheological properties were investigated weekly. During frozen storage dough extensibility increased, while elastic and viscous moduli decreased. Differential scanning calorimeter and nuclear magnetic resonance data indicated that WB and WB + G dough products contained approximately 10% less freezable water and 9% more bound water compared to the control dough (W). β‐Glucan enriched dough also exhibited less changes in gluten network as shown by SEM photographs. The addition of air‐classified barley flour fraction at 10% in frozen dough reduced deterioration effects caused by frozen storage via minimizing water redistribution and maintaining rheological properties of frozen dough.  相似文献   

3.
BACKGROUND: Waxy wheat, a new kind of genetically back‐crossed wheat, was applied to make whole bread in this study. Dough properties and bread quality of the whole waxy wheat flour, which was milled from 100% whole grains containing bran and germ, were determined. RESULTS: Whole waxy wheat had lower protein and lipid contents but higher dietary fiber content than whole regular wheat flour. Pasting temperature and viscosity of the whole waxy wheat flour were significantly lower than those of the whole regular wheat. However, the white wheat flour milled from wheat grains with 48% recovery had significantly higher peak viscosity than the whole waxy wheat. Bread made from the whole waxy wheat flour was significantly softer than that from the whole regular wheat flour during storage. However, bread made from whole waxy wheat had significantly lower specific volume than that from the white waxy flour because of the high amount of dietary fiber. Addition of cellulase increased paste viscosity, lowered dough mixing properties and reduced the firmness of the bread. The addition of pentosanase also increased paste viscosity, lowered dough mixing properties, improved loaf volume of bread but increased the firmness of breadcrumbs, while the addition of α‐amylase only increased final viscosity of flour and did not affect dough properties and bread qualities of whole waxy wheat flour. CONCLUSION: As a result, waxy wheat shows superior properties for making whole breads. Additional enzymes are also necessary to improve bread quality and nutritive values of whole waxy bread. Copyright © 2007 Society of Chemical Industry  相似文献   

4.
Use of Enzymes to Minimize Dough Freezing Damage   总被引:1,自引:0,他引:1  
The purpose of this investigation was to study the effect of pentosanase (Pn), glucose oxidase (Gox), and transglutaminase (TG) on frozen dough (−18 °C) and their influence on minimizing the damage caused by frozen storage. Bread characteristics were analyzed on day 0; after 3 and 9 weeks of frozen storage, specific loaf volume, crust color, and crumb texture and structure were analyzed. Dough expansion capacity and dough stickiness, extensibility, and viscoelasticity were determined. Frozen dough with high levels of Gox developed a larger bread volume than control dough (without added enzyme). The damage percentage caused by frozen storage in Gox samples was lower than in control samples, indicating that Gox increased dough strength and counteracted the depolymerization effect of gluten produced by ice crystal formation and the release of reducing substances from dead yeast cells during freezing. Samples with Pn developed a large bread volume after 9 weeks of frozen storage because of the formation of smaller pentosans, which result from Pn enzyme action. These pentosans were located in protein–starch–CO2 matrix interfaces and increased dough expansion capacity without gas loss, thus allowing a higher expansion during proofing. The intermediate level of TG was the only one to present a larger bread volume from frozen dough than control. The new isopeptidic bonds introduced by TG in the gluten proteins helped to mitigate the damage caused by dough freezing.  相似文献   

5.
本文研究了海藻酸丙二醇酯(Propylene glycol alginate,PGA)对全麦冷冻面团冻藏期间稳定性的影响,并探究了冷冻面团烘焙面包品质的变化。将0.3%的PGA加入全麦面团,通过测定冷冻面团冻藏1、2、3、4和5周后发酵特性、流变特性、蛋白质二级结构、微观结构以及面包的比容、质构特性、内部纹理结构和老化程度等,研究冷冻面团冻藏期间的稳定性。结果表明,随着冻藏时间的延长,添加PGA的冷冻面团在冻藏5周后具有较好的保水性,其发酵特性及流变特性相对于对照组均有所改善。冻藏5周后,对照组与PGA组其面包比容分别下降了19.872%和14.153%;面包硬度分别升高了64.186%和36.386%;气孔表面积分率分别下降了3.497%和2.300%;老化焓值分别上升了65.142%和42.416%。添加PGA能延缓冷冻面团冻藏期间β-折叠含量的上升和β-转角相对含量的下降。电镜扫描图(SEM)显示,随着冻藏时间的延长,PGA组的冷冻面团孔洞数目相比对照组明显减少且大小均匀,面筋网络结构完整性和连续性提高。研究结果表明PGA可以有效地延缓冷冻面团在冻藏期间的品质劣变,维持冷冻面团的稳定性并提高面包的烘焙特性。  相似文献   

6.
Jinhee Yi 《LWT》2009,42(9):1474-1483
This study compares the effects of freezing temperature and rate as well as storage temperature and time on the quality of frozen dough. Yeasted bread dough was frozen using four freezing rates (19-69 °C/h), then stored at −10, −20, −30, or −35 °C for up to 180 days. Dough strength diminished with longer storage time and higher storage temperatures. Cryo-SEM showed that dough stored at −30 and −35 °C had the least damaged gluten network. NMR studies showed that more rapidly frozen dough, and that stored at lower temperatures had lower transverse relaxation (T2) times (9-10 ms). However, dough stored at −20 °C displayed the highest yeast activity among samples. Bread loaf volume decreased with storage time, and bread made from dough stored at −20 °C showed the highest loaf volume. Breads produced from −30 and −35 °C stored dough displayed less change in the texture profile during storage as well as less change in T2 values. Response surface analysis showed that optimal properties occurred at freezing rates of around 19-41 °C/h and storage temperatures of −15 to −20 °C.  相似文献   

7.
将藜麦和小麦粉按一定比例混合,用快速粘度分析法测定混合粉糊化特性,流变仪测定了冻藏过程中小麦-藜麦冷冻面团的流变学特性,核磁共振法测定面团中水分迁移,并测定其发酵体积变化,最后分析了冷冻面团组织状态与产品品质的关系。结果表明:藜麦粉对冷冻面团及面包的品质均有改善。藜麦粉降低了混合粉体系的糊化粘度和崩解值。冻藏后,冷冻面团的弹性模量和粘性模量增加,小麦粉冷冻面团损耗角正切值增加了4.73%,添加量为5%时冷冻面团损耗角正切值仅增加0.41%;小麦冷冻面团自由水上升了3.90%,藜麦添加后仅上升2.40%,可见藜麦粉能冷冻面团降低水分迁移程度;同时,添加藜麦粉能维持面团面筋网络结构的完整性,发酵体积由26.42 mL/h增大到29.17 mL/h。不同添加量的藜麦粉对面团及面包的品质改善程度不同,最适添加量为10%,烘烤后面包比容为3.08 mL/g,硬度为2803.48 g。本研究可为开发藜麦冷冻面团提供理论基础,在藜麦新产品开发方面具有重要的指导意义。  相似文献   

8.
The importance of polyunsaturated fatty acids (PUFA) in health and nutrition is well recognised. Flaxseed (Linum usitatissimum) has recently gained a lot of attention as functional food because of its unique nutrient profile. In the present work efforts were made to develop omega-3 enriched functional bread using raw and roasted ground flaxseed flour. Initially optimisation of each bread ingredient viz., salt, sugar, and shortening, GMS, yeast and water was carried out on the basis of sensory overall acceptability score. The standardised bread was incorporated with raw and roasted ground flaxseed (5, 10, and 15 g/100 g) flour. The effect of flaxseed incorporation on bread dough rheology parameters viz., dough stickiness and water absorption was studied. Increase in water absorption and dough stickiness was observed with increased flaxseed level. Further breads were evaluated for sensory parameters, colour and texture. The crumb softness increased with increase in flaxseed level. Bread was optimised at 10(g/100 g) flaxseed level based on sensory evaluation.  相似文献   

9.
研究通用中筋粉在常温(25℃),不同湿度(50%、65%、80%)条件下储存过程中面粉中水分含量、粗蛋白质含量、湿面筋含量、脂肪酸值等指标及其制作面团的酸度和馒头的感官品质的变化。实验结果表明,在湿度80%条件下,随着储存时间的延长面粉水分含量变化显著(p<0.05)。同一储藏时间,湿度越高,面筋含量越低。不同湿度(50%、65%、80%)条件下,面粉中的脂肪酸值都随储存时间的增加而增加(p<0.05)。不同湿度(50%、65%、80%)储存过程的面粉制作的发酵面团的酸度都呈现先降低后增加的趋势,制作馒头的感官评分呈现下降的趋势(p<0.05)。面粉在不同湿度(50%、65%、80%)储存过程中,储存30 d的面粉,醒发后面团酸度都显著下降(p<0.05);继续延长储存期,在湿度50%下的面粉制作的面团酸度有回升,但不超过原始的面团酸度,随储存湿度提高面团酸度增加明显;感官评分表明,储存环境湿度越高,面粉制作的馒头品质下降越快,湿度80%储存60 d后的面粉制成的馒头口感差。湿度50%存放120 d仍可用于加工馒头。结论:面粉储存过程中,湿度越大,面粉品质下降越快,进而影响到所制作的馒头品质。  相似文献   

10.
Two different green tea extracts (GTE‐A and ‐B) as a rich source of tea catechins were incorporated into a no‐time bread‐making process, where bread made from the unfrozen and frozen dough processes was compared by specific volume and texture profile. GTE‐A and ‐B both exhibited significant effects on bread volume and firmness, but to a different extent. GTE‐A with higher content of tea catechins (73%) at a level of 1.5 g kg?1 flour was found to lead to a significant reduction in bread volume in unfrozen dough process and an increment in firmness during storage for 4 days at ambient temperature (22 °C). GTE‐B, with a lower content of catechins (60%), had relatively mild effects on the bread quality. Significantly negative effects were evident starting at a higher level of 5.0 g kg?1 flour in unfrozen dough process. Frozen storage showed more predominant deteriorating effects than the GTEs over a period of 9 weeks frozen storage at ?20 °C. Copyright © 2006 Society of Chemical Industry  相似文献   

11.
This article presents a novel idea for the preparation of frozen dough and steamed bread by which black rice flour (BRF) with different particle sizes (0.18–0.25 mm, 0.15–0.18 mm and 0.125–0.15 mm) was added into wheat flour (WF), considering the nutritional values of BRF. The characteristic of the composite flour (CF), frozen dough and steamed bread was studied. CF had higher contents of dietary fibres (2.01–2.16%) but lower content of protein (11.57–11.92%) compared with WF (1.6% and 12.60%, respectively). Correlation analysis showed that the addition of BRF could alleviate the damage to dough caused by freezing, which may be due to that water in CF dough was more stable. The content of freezable water in WF dough increased by 23.48%, while that in CF dough increased by 6.09–12.11% after frozen storage. With decreasing particle size, the hardness of CF dough decreased and the resistance to extension and gas retention coefficient increased, whereas the specific volume and the soft crumb texture of CF steamed bread increased. In short, small-sized BRF is more suitable for use in the preparation of steamed bread.  相似文献   

12.
质构仪在面团和面包品质评定中的应用研究(英文)   总被引:9,自引:1,他引:9  
郑铁松 《食品科学》2004,25(10):37-40
以八种品牌面粉为试验材料,采用英国 CNS-FARNELL 公司制造的质构仪测试了面团的硬度、弹性、粘力、粘着性、断裂力、断裂能量、断裂回复形变程度、回复能量、回复形变程度等九种指标,并通过相关分析研究了这些指标与面包品质(面包体积和弹性变化率)以及与小麦面粉的品质性状的相互关系。研究结果表明:面团的硬度、粘力与面包的体积呈正相关,相关系数分别为 0.546、0.568,弹性与面包的体积呈负相关,相关系数为-0.606;粘力与24h后室温下弹性变化率呈显著的正相关,相关系数为0.707。面团的质构特性与面粉的品质指标的相关性也非常明显。  相似文献   

13.
The application of Chinese steamed bun starter dough (CSB-SD) in breadmaking was investigated. The activation of CSB-SD to activate the growth of lactic acid bacteria (LAB) and to increase the number of yeast, prior to making bread, was conducted by mixing CSB-SD with wheat flour and water and then incubating for 24 h. Wheat flour was then substituted by this activated CSB-SD (aCSB-SD) at 10%, 30%, and 50% (w/w) to make bread. Dough and bread properties were studied comparing to the control (without aCSB-SD). From the farinograph results, a high aCSB-SD substitution level resulted in a less stability in dough with a higher degree of softening. Extensigraph results suggested that after aging, all the substituted dough yielded a greater resistance to extension with lower extensibility values than the control. Substitutions with 30% and 50% (w/w) aCSB-SD significantly increased the total CO(2) gas generation. Scanning electron microscopy SEM images of the 30% and 50% (w/w) substituted dough showed a well-developed gluten matrix. The 50% (w/w) substituted breads obtained a greater risen volume, finer crumb grain, and retained more softness after 5-d storage than the control. In addition, both the 30% and 50% (w/w) substituted breads showed a slightly increased mold stability, as compared to the 0% and 10% (w/w) substituted breads.  相似文献   

14.
Texture properties of wheat doughs were determined with a texturometer by using texture profile analysis (TPA) as well as Chen and Hoseney methodologies. The time elapsed between two compressions and strain were optimized so that meaningful values were obtained for TPA. Single effects and interactions between flour type, the breadmaking process and anti-staling additives (i.?e. monoglycerides, diacetyl tartaric ester of monoglycerides, sodium stearoyl lactylate, carboxymethylcellulose and hydroxypropylmethylcellulose) on dough texture properties (i.?e. springiness, resilience, hardness, cohesiveness, adhesiveness, chewiness, gumminess and stickiness) were estimated. The breadmaking process and addition of hydrocolloids had the most important effects and interactions on TPA. Hydrocolloids and α-amylase increased dough stickiness. Dough cohesiveness was a good predictive parameter of bread quality. Water content, acidity values and gluten quality were the main factors determining the texture properties of dough.  相似文献   

15.
Free amino acids, peptides, and vital wheat gluten were investigated to determine their effect on the mixing and frozen dough baking properties of wheat flour. Addition of 1% cysteine and aspartic acid decreased and glutamic acid, histidine, arginine, and lysine increased the mixing tolerance of flour. Cystine, methionine, tryptophan, and phenylalanine increased but isoleucine, histidine, glycine, arginine, glutamic acid, aspartic acid, and lysine decreased loaf volume of nonfrozen dough breads. However cystine, methionine, tryptophan, and phenylalanine did not increase loaf volume of bread prepared from frozen dough. Vital wheat gluten increased mixing tolerance and bread loaf volume only for the nonfrozen dough. However, wheat gluten hydrolysate, corn, and bonito peptides decreased mixing tolerance after optimum mixing time and were effective in increasing loaf volume for both frozen and nonfrozen dough. As the amount of corn and bonito peptide increased, specific loaf volumes also increased. Addition of 2.5% corn peptide was most effective in increasing loaf volume of frozen dough bread. Crust browning and crumb stickiness increased, whereas crumb softness decreased with addition of peptides. Addition of less than 1% peptide did not adversely affect the aftertaste and off‐flavor of bread. These results suggest that addition of peptides are effective for improving the baking quality of frozen dough, whereas amino acids and gluten have no effect.  相似文献   

16.
目的 探讨不同全麦粉替代率对冷冻馒头品质影响的变化规律.方法 采用不同比例全麦粉(0、10%、20%、30%、40%、50%、60%、70%、80%、90%、100%)替代小麦粉,测定了混合粉的湿面筋含量和流变学特性,对比新鲜馒头,评价全麦粉替代率对冷冻馒头外观、质构和感官品质的影响.结果 随全麦粉替代率增加,面团湿面...  相似文献   

17.
The textural properties of wheat doughs made with different commercial amylases, xylanases/pentosanases, lipases and glucose-oxidase, singly and in mixed combinations, were investigated. Parameters from the texture profile analysis (TPA) and measurement of stickiness (Chen and Hoseney test) were determined after mixing the dough and after it had rested for 3.5 h. Resting of doughs led to softer and less cohesive doughs, with higher adhesive properties. Enzymes acted quickly and induced significant changes in the textural properties of doughs immediately after mixing. The influence of enzymes continued during resting. Xylanases/pentosanases substantially reduced dough consistency and increased stickiness, while addition of glucose-oxidase and specific lipases overcame these effects. Strong correlations could be established between different TPA parameters and stickiness and bread quality characteristics (i.e. volume, density and texture). Bread quality could be described by a single or multiple linear combination of textural variables.  相似文献   

18.
将以棕榈油和大豆油为原料制备的专用油脂应用于冷冻面团中,研究专用油脂对冷冻面团流变学特性影响及对冷冻面团焙烤面包品质的影响。结果表明:添加专用油脂制备的冷冻面团面包比容大、纹理细腻、口感柔和、品质良好;专用油脂可以有效地提高冷冻面团的筋力和延伸性,并能延缓冷冻面团因冻藏导致的焙烤品质下降,对延缓面包老化效果良好;确定专用油脂在冷冻面团中的添加量为配方中面粉质量的6%。  相似文献   

19.
BACKGROUND: Ozone gas could be used as a fumigant during grain and flour storage. Experiments were conducted to determine the effects of exposure to ozone and the effects of blending ozone‐treated flour with control flour on flour functionality and bread‐making quality. RESULTS: Ozone treatment oxidized lipids, increased brightness and reduced the yellow hue of flour, and increased peak viscosity and setback viscosity of flour. Bread made from flour treated with ozone at 1500 mg kg?1 for 4.5 min and bread made from flour blended with 100 g kg?1 ozonated flour had good crust color and a whiter crumb and had more crumb cells, which resulted in a greater specific volume of the bread when compared with control flour. Flour functionality declined as ozone exposure increased beyond 9 min and as the concentration of ozonated flour increased beyond 200 g kg?1. CONCLUSION: Bread made from flour exposed to ozone for 4.5 min or flour that contained 100 g kg?1 fully ozonated flour had greater specific loaf volume and whiter crumb compared to bread made with control flour. Exposure of flour to ozone for longer times (9–45 min) and higher blends (200–1000 g kg?1) deteriorated quality of bread. Copyright © 2011 Society of Chemical Industry  相似文献   

20.
Response surface methodology was used to investigate the influence of three factors namely mill aperture, feed rate and moisture content of wheat grain on the damaged starch content of whole wheat flour from Lokwan wheat cultivar, dough stickiness and chapatti (Indian unleavened flat bread) quality. Each predictor variable was tested at three levels. Aperture was varied as 2, 3 and 4 mm in a stone mill, feed rate as 0.21, 0.63 and 1.05 min for 200 g wheat grains and grain moisture content as 8.6, 14.3 and 20% w/w. Flours containing varying amounts of damaged starch ranging from 6.1% to 26.90% were obtained and these were evaluated for dough stickiness and chapatti quality. Dough stickiness was increased with decreased aperture. With decreased aperture and increased grain moisture content softness of the chapatti was improved.  相似文献   

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