Impact of endogenous constituents from different flour milling streams on dough rheology and semi-sweet biscuit making potential by partial substitution of a commercial soft wheat flour

A flour fractionation-reconstitution procedure was used to study the substitution of a commercial soft wheat flour with gluten, water extractables, prime starch and starch tailing fractions isolated from patent and clear flour streams on dough rheology and semi-sweet biscuit characteristics. Substitution of soft wheat flour with increasing levels of the native patent and clear flour streams raised the dough consistency, hardness and elastic properties as well as the biscuit textural attributes (density, hardness). The dough stickiness of the base flour was also reduced and the biscuits were free of cracks. Gluten isolated from the patent flour had a greater impact on dough consistency, hardness and elastic properties than gluten obtained from the clear flour, likely due to the superior protein quality of the former. Additionally, with increasing gluten levels in the fortified flour there were moderate increases in biscuit density, hardness, and lower crunchiness. The addition of starch tailings produced the largest impact on consistency and hardness of the dough. This fraction also exerted a pronounced effect on biscuit density and hardness, while it lowered crunchiness, presumably due to its higher pentosan content. Overall, the dough rheological properties and biscuit characteristics were controlled by the amount-nature of the fractions added; i.e., besides gluten (amount and quality), other constituents such as pentosans and the overall composition of the flour blends can largely affect the quality of the semi-sweet biscuits.     

Olive stone powder: A potential source of fiber and antioxidant and its effect on the rheological characteristics of biscuit dough and quality

Being waste products of olive fruits, olive stones could be used as a healthy functional food ingredient thanks to their rich antioxidant properties, nutrients and dietary fibers. In this study, wheat flour was substituted by olive stone powder at levels of 0, 5, 10 and 15%. The rheological properties of biscuit dough and proximate composition, color values, total phenolic content, antioxidant activity, textural characteristics and sensorial properties of biscuit samples were investigated. Wheat flour replacement by olive stone powder increased antioxidant activity, fat and fiber content of biscuit samples (p < 0.05). The biscuits prepared with addition of 15% olive stone powder had 30.44 ± 0.03% DPPH radical scavenging activity, 11.22 ± 0.09% crude fiber, and 26.32 ± 0.22% fat. According to results of sensory analysis, wheat flour could be substituted up to 15% by olive stone powder to prepare biscuits without causing unacceptable product in terms of sensory properties.     

鹰嘴豆全麦粉酥性饼干研制及品质分析表征

目的为开发一款低糖、低脂、富含氨基酸和膳食纤维的功能性饼干。方法以低筋粉、鹰嘴豆、全麦粉、玉米油等原料研制鹰嘴豆全麦粉酥性饼干,以感官评分为评定指标经单因素和正交试验优化得到最优配方。采用质构仪和低场核磁共振分析表征了不同组分条件下鹰嘴豆全麦粉酥性饼干的内在结构和水分分布情况。结果通过正交实验优化了鹰嘴豆全麦粉酥性饼干配方为：鹰嘴豆粉17.5%、全麦粉30%+低筋粉70%、木糖醇25%、玉米油22.5%。在此配方下制得的鹰嘴豆全麦粉酥性饼干感官评分最高且硬度、脆性、胶黏性和咀嚼性均高于其他试验组。结论本研究为膳食纤维功能饼干研发与生产提供理论参考。     

Effect of mustard flour incorporation on nutritional, textural and organoleptic characteristics of biscuits

Nutritional, sensory and textural characteristics of defatted mustard flour fortified biscuits were studied to optimize the mustard flour supplement in the blend for making biscuits. The wheat flour was replaced by defatted mustard flour at 5, 10, 15 and 20% incorporation levels in biscuit preparation. The protein content of mustard flour biscuit increased nearly 2.5 times as a result of mustard flour incorporation, coupled with reduction in fat and an increase in fiber content. Sensory evaluation results revealed that the sample containing 15% defatted mustard flour scored highest in most of the attributes including overall acceptability. Textural characteristics of all dough and biscuit upto 15% supplement of defatted mustard flour were similar while at 20% level, the values were significantly different. The study reveals that incorporation of 15% defatted mustard flour gave desirable results in terms of nutritional, sensory and textural attributes of mustard fortified biscuits.     

红薯泥饼干的研制

将红薯制成红薯泥,并以此为原材料加工红薯食品,可提高红薯食品的食用价值。通过正交试验确定产品的最佳配方为：红薯泥300 g∶低筋面粉300 g∶糖100 g∶猪油140 g。通过测定红薯泥饼干的理化指标,证明红薯泥制品抗氧化物总量多于普通饼干,更对人体健康有益。     

Biscuit making properties of flours from hard and soft milling single variety wheats

Bench scale baking tests for two types of biscuits,¹ a hard sweet (HS) and a short sweet (SS), have been used to examine the biscuit making properties of a large number of flour samples from wheats grown in four consecutive years (1980–1983). Multiple regression models for prediction of biscuit properties using a range of standard cereal laboratory tests as independent variables on results from 1980–1981 harvest wheats confirmed earlier observations that such tests are of limited commercial value for biscuit flour specification. However the results of baking tests, with both types of biscuit, from single wheat varieties grown during 1981–1983 showed that flours from soft milling wheats (SMW) required less water to give biscuit doughs of standard consistency (measured instrumentally) than did flours from hard milling wheats (HMW). In addition biscuit doughs made with SMW flours gave greater oven spring, i.e. biscuits of lower bulk density, than doughs made from HMW flours. In each season the difference in the mean values of both parameters for flours milled from SMW and HMW was highly significant (P<0.001). With one exception the variability of the measured parameters within seasons was not significantly different between SMW and HMW. However within both SMW and HMW varieties highly significant differences (P<0.001) were observed between seasons for the mean values of both measured biscuit parameters. The effect of flour particle size on the biscuits was studied by regrinding a number of flours. With flours from both SMW and HMW reduction in particle size resulted in HS biscuits of higher density but SS biscuits of lower density.     

Influence of gluten-free flour mixes and fat powders on the quality of gluten-free biscuits

Studies were conducted to develop gluten-free biscuits comparable in quality to wheat (W) biscuits and superior to those made from commercial gluten-free flour (Gf), suitable for coeliac sufferers. Three mixes of brown rice flour (R), corn starch (C), potato starch (P), soya flour (S), buckwheat flour (B) and millet flakes (M) were studied: RCPS in the percentage 70, 10, 10, 10, RPBM (50, 30, 10, 10) and RCPM (25, 25, 25, 25). Biscuits were tested for water activity, moisture, texture (snap test), diameter, thickness and colour (L* value), biscuit dough for hardness and stickiness. Various correlations >0.8 indicated for the three mixes, W and Gf that firm, non-sticky doughs yielded firm, thin, non-oval biscuits. Cluster analysis revealed that RCPS was most similar to W with regards to all parameters measured, and RCPS also showed best overall acceptability in sensory testing. Three fat powders were studied for use instead of palm oil: high and low fat dairy powder (HFP, LFP) and microencapsulated high fat powder based on vegetable fat (ME). HFP and ME yielded biscuits of comparable texture to palm oil, LFP resulted in much firmer biscuits, attributed to lower fat and higher protein and total sugar content.     

Protein nutritive quality during production and storage of dietetic biscuits

A comparative investigation of the changes in available lysine content during industrial production of two dietetic hard biscuits based on whole grain wheat flour/grits and a standard hard biscuit based on white wheat flour was performed. Dough preparation did not significantly affect the available lysine content. However, after baking, a significant loss (27–47%) of available lysine was found in all three types of biscuit. The average relative decrease in available lysine in proteins of each type of biscuit correlated highly significantly with technological parameters, mainly with the interaction between baking temperature and baking time (r = 0.980, p = 0.001). Physical characteristics of the biscuits, such as thickness, surface area, weight and density, also contributed considerably to the extent of damage to available lysine. The two dietetic biscuits were characterised by a higher available lysine content than the standard biscuit, and accordingly by a higher protein nutritive quality, with average chemical scores (calculated for adults) of 97 and 105 as against 60 for the standard biscuit. Storage for a long time (1 year) had no significant influence on the chemical scores. © 2002 Society of Chemical Industry     

Characterisation of flour, starch and fibre obtained from sweet potato (kumara) tubers, and their utilisation in biscuit production

Sweet potato (kumara) tubers of differing colours (orange, red and white) were used to produce tuber flour, a purified starch fraction and an isolated fibre extract. The fractions from each tuber colour were added into a biscuit mixture, and the effects of tuber source and fraction composition were observed in relation to the physico-chemical characteristics of biscuits. Addition of sweet potato flour and fibre fractions to white wheat flour significantly reduced the pasting properties (peak and final viscosity) of the resulting gels by up to seven-fold compared with the control wheat flour gel (as determined by the Rapid Visco Analyser). The addition of sweet potato starch affected the pasting properties of wheat flour–sweet potato starch mixes to a lesser extent. Biscuit texture (force required to cause a biscuit to fracture) was significantly reduced with the incorporation of sweet potato fibre into the biscuit dough preparation, this was linked to a reduction in biscuit thickness and spread ratio. However, the addition of sweet potato flour and starch resulted in biscuits of similar firmness as the control biscuits.     

Semi-Sweet Biscuits: 2. Alternatives to the Use of Sodium Metabisulphite in Semi-Sweet Biscuit Production

The influence of sodium metabisulphite (SMS) and other gluten-modifying agents on the performance of a commercial biscuit flour in the production of semi-sweet biscuits has been studied. Use of a proteolytic enzyme as a gluten-modifying agent resulted in a dough with a longer mixing time than other doughs, partly as a result of mixing to a higher temperature. The extrusion time of doughs containing the proteolytic enzyme was closest to the extrusion time of doughs containing SMS. Doughs containing SMS or proteolytic enzyme produced significantly shorter extrusion times than doughs containing l -cysteine hydrochloride. Dynamic oscillatory measurements showed that for doughs made at a constant water level the lowest elastic and viscous moduli were produced by doughs containing sodium metabisulphite. Doughs containing the other gluten-modifying agents produced stronger elastic properties than those containing SMS but weaker elastic properties than doughs containing no gluten-modifying agent. The hardness of the semi-sweet biscuits produced was found to be reduced by a weakening of the rheological properties of the dough. All gluten-modifying agents reduced dough piece contraction in length during processing, although SMS was the most effective. A decrease in dough piece length during processing caused an increase in dough piece thickness and width. Use of a proteolytic enzyme or the enzyme and l -cysteine hydrochloride in combination, as gluten-modifying agents, produced biscuits closest in quality to those produced from doughs containing SMS.     

Evaluation of sugar replacers in short dough biscuit production

Sugar inhibits gluten development during dough mixing by competing with the flour for the recipe water, resulting in less tough and more crumbly biscuits. Commercially available Raftilose, which acts as an oligofructose and a sugar replacer was used in the recipes where the sugar was reduced by 20–30%. It was found that the sugar replacer did not exert the same hardening effect on the dough as the granulated sugar, therefore values for dough hardness were found to be lower than those obtained for the standard biscuit. Peak force values of the reduced sugar biscuits were found to be significantly lower than the control biscuit (P<0.05), indicating a lower snapping characteristic, and therefore softer eating characteristics. Only those biscuits with the highest level of sugar replacement showed different surface colour attributes. At the lower and medium levels of sugar replacement, oligofructose can be used successfully to reduce sugar in short dough biscuits.     

麦麸对酥性饼干物理性质和淀粉消化性的影响

目的 研究麦麸对酥性饼干颜色、物理性质以及淀粉消化性的影响。方法 将麦麸按0～50%比例添加到面粉中制作饼干,测定混合粉的溶剂保持力,测定饼干颜色、延展度、硬度以及淀粉消化性。结果 添加麦麸导致混合粉的水和碳酸钠溶剂保持力值增加,乳酸溶剂保持力值和面筋性能指数降低(4.71%～33.20%和25.73%～34.11%),饼干颜色变暗。当麦麸添加量大于20%时,饼干的延展度和硬度增大(53.54%～64.31%和135.98%～408.53%)。此外,麦麸的添加在一定程度上降低了饼干淀粉消化性。麦麸添加量与饼干物理性质呈强正相关性,与消化终点葡萄糖含量呈负相关。通过主成分分析,提取了2个主成分,累计方差贡献率为85.3%。结论 适量添加麦麸有效改善了饼干酥脆性,并在一定程度上抑制了饼干淀粉的消化,增加了饼干的功能性质,可以为麦麸产品的进一步开发提供参考。     

Nutritional Evaluation of Breadfruit-containing Composite Flour Products

Composite flours containing wheat, breadfruit flour and soy protein, whey or peanut meal were formulated and incorporated into western style bread and biscuits. Bread containing 10% breadfruit flour and 5% whey, and biscuits containing 10% breadfruit flour and 5% soy protein were judged most acceptable in flavor, color, and texture. Breadfruit flour contained 4.4% protein and was lower in sulfur containing amino acids and higher in lysine than wheat flour. Breadfruit containing bread and biscuits had low amino acid scores. The protein efficiency ratio (PER) of the biscuit product, however, was similar to that of the casein control while the PER of bread was significantly lower. Results suggest that acceptable products can be made with composite flours containing 10% breadfruit flour.     

计算机辅助X光断层扫描对半甜韧性饼干的质构无损量化检测

采用X光计算断层扫描（X-ray computed tomography,CT）法研究了半甜韧性饼干（以下简称饼干）的 质构特征,并将CT参数与饼干常规物理参数进行了相关性研究。结果显示：CT测试所获得的组织重构可以直观再 现饼干的内部结构（二维及三维）;CT密度、孔隙率以及气泡截面积的平均值与饼干面团中蛋白酶或焦亚硫酸钠 （以下简称焦亚）的添加量、饼干厚度以及表观密度具有显著相关性（R＞0.9,P＜0.05）,反映出CT参数可以客 观地量化由于蛋白酶或焦亚添加量不同所导致的饼干组织结构变化。当蛋白酶或焦亚对面团产生程度相当的减弱面 筋（减筋）作用时,两种面团饼干的常规物理参数及CT参数均表现出显著性差异（P＜0.05）,并且饼干气泡截面 积的分布也表现出不同的特征,表明CT参数可以反映由于不同的减筋原理导致的饼干质构差异。结果表明,CT测 试可以应用于饼干质构的定性和定量测定,为饼干的生产与研究提供有益的信息。     

豆渣膳食纤维对酥性饼干特性的影响

将豆渣中酶法提取的可溶性膳食纤维(豆渣SDF)、不溶性膳食纤维(豆渣IDF)以及商业菊粉,分别添加到酥性饼干中,研究其对饼干的物理化学特性和感官品质的影响。结果表明:添加豆渣IDF的饼干持水性和硬度较高,添加豆渣SDF和菊粉的饼干松密度值和过氧化值较低,且两者的松密度值没有较大差异,而添加豆渣IDF的饼干与之相反,添加4%豆渣SDF的饼干感官评定结果最优,且总膳食纤维、水分和脂肪含量较空白高,而蛋白质和灰分含量没有明显变化。     

Feasibility of use of buckwheat flour as an ingredient in ginger nut biscuit formulation

Ginger nut biscuits are popular traditional biscuits which contain honey. In order to improve their nutritive profile and functionality, standard formulation based on wheat flour was substituted with buckwheat flour at three levels (30%, 40%, 50%). The quality attributes (chemical composition, microelements, bioactive compounds (total polyphenols, rutin, quercetin), antioxidative potential, textural and sensory properties) were compared to control biscuit (based on wheat flour) and biscuits substituted with rye at the same levels, since rye is used as an ingredient which improves the quality of ginger nut biscuits. Substitution with buckwheat flour resulted in a significant increase (p < 0.05) in protein, Zn, total polyphenols, antioxidative and chelating activity. Total dietary fibre, Cu, Mn and Fe contents also increased but did not exceed those in rye substituted biscuits. Consumption of 100 g of enriched biscuits could contribute to reaching ≈18–22% (buckwheat) and 16–17% (rye) of the estimated daily average total polyphenols intake, respectively. With the contents of rutin and quercetin at 3.96–6.57 mg/100 g d.b. and 0.087–0.214 mg/100 g d.b., respectively, buckwheat substituted biscuits may significantly contribute to total dietary flavonoid intake and meet the demands of preventive nutrition. Buckwheat enriched biscuits were rated higher regarding sensory attributes, softness and fracturability as compared to control but lower compared to rye supplemented biscuits.     

Effect of native and germinated finger millet flour on rheological and sensory characteristics of biscuits

Wheat flour was replaced with native finger millet flour (NFMF) and germinated finger millet flour (GFMF) at 30–50% levels to make soft dough biscuits. Dough rheological properties and baking characteristics of the blends were evaluated. Farinograph data of wheat flour replaced with NFMF and GFMF showed a decrease in water absorption, dough stability and an increase in mixing tolerance index as the level of replacement increased. Extensibility of dough decreased for both NFMF and GFMF as the levels increased. The hardness of biscuit dough measured by texture profile analysis increased from 125 to 234 N for NFMF and 118 to 126 N for GFMF. Scanning electron microscopic studies on the biscuit dough showed polygonal finger millet starch granules adhering to wheat starch granules and protein matrix. The results of the study indicated that the replacement level of 40% with either NFMF or GFMF produced biscuits with acceptable sensory attributes. Addition of sodium stearoyl‐2‐lactylate (SSL) showed further improvement in terms of spread ratio, surface characteristics and texture.     

全谷物发芽糙米韧性饼干制作工艺优化

为了拓展发芽糙米的利用途径,丰富全谷物食品种类,本文以发芽糙米粉替代部分小麦粉应用于饼干,开展了配方及焙烤工艺参数对韧性饼干品质特性的影响研究,优化了饼干的制作工艺.结果表明,随着发芽糙米粉的增加,饼干色泽降低,硬度呈上升趋势,延展度、感官评分均呈先增加后降低的趋势;增大黄油的添加量,延展度、膨松度变化较小;增大糖粉的...     

荷叶粉对面粉理化性质及酥性饼干品质的影响

目的:探索酥性饼干中荷叶粗粉与荷叶超微粉适宜添加量。方法:采用粉质仪、拉伸仪、湿面筋仪、降落数值仪测定荷叶粗粉与荷叶超微粉对面粉理化指标的影响,采用质构仪测定面团的硬度和酥性饼干的剪切力,采用感官方法评价酥性饼干的感官品质,采用菌落总数测定方法测定原料与酥性饼干的细菌总数。结果:在面粉中添加0%~15%的荷叶粗粉与荷叶超微粉,能够增加面粉的吸水率、降落数值和面团的硬度,降低面粉的稳定时间、面团的拉伸能量和湿面筋含量,酥性饼干的酥松度和感官评分先增加后下降,当面粉中荷叶粗粉添加量为6%、荷叶超微粉添加量为9%时,酥性饼干酥松度和感官评分最大,此时与空白相比,酥性饼干的感官评分分别提高9.81% 和18.33%,荷叶超微粉添加量比荷叶粗粉高出3%。与空白相比,添加15%荷叶粗粉的酥性饼干其细菌总数下降41.18%,添加15%荷叶超微粉的酥性饼干其细菌总数下降62.94%。结论:荷叶粗粉与荷叶超微粉能够增加酥性饼干的营养价值和感官品质,超微粉效果比粗粉更好。     

Mechanical and fracture properties for predicting cracking in semi-sweet biscuits

Mechanical and fracture properties required for predicting crack development in semi‐sweet (‘rich tea’) biscuits have been experimentally determined. Pilot‐scale biscuits of different fat concentrations were prepared and studied with commercial biscuits at different moisture contents. Bending modulus, fracture stress and strain were measured using three‐point bending tests. All biscuit types showed considerable dependence on moisture content over a range of 4–12%. Young's modulus and failure stress showed a uniform decrease and failure strain showed an increase with increasing moisture content. For pilot‐scale biscuits of different fat concentrations, an increase in fat level caused a decrease in modulus and failure stress values; however, the failure strains were very similar for all the fat types. The testing of the samples with top surface up and top surface down revealed that the sample orientation does not affect the measured parameters. The measured parameters also did not show any directional dependence within the plane, thus assuring that the assumption of an isotropic material would be valid for modelling. The mechanical and fracture properties measured in this study will serve as a very useful set of data to predict the stress state and cracking of the checked biscuits.