食用胶对小麦粉面团流变学特性的影响

为明确食用胶在面制食品中的作用,以3种商业小麦粉(特一粉、富强粉、上白粉)为试验材料,分别添加不同比例的海藻酸钠、黄原胶、卡拉胶,分析其对面团流变学特性的影响。结果表明,小麦粉添加0.15%~0.25%的海藻酸钠,面团稳定时间显著提高,弱化度显著降低;添加0.10%、0.20%和0.25%的海藻酸钠,面团最大拉伸阻力显著提高。添加0.02%、0.06%和0.10%的黄原胶,面团最大拉伸阻力显著提高;添加0.10%黄原胶的面团拉伸面积也显著提高。添加0.10%的卡拉胶,面团稳定时间、拉伸面积显著提高,弱化度显著降低。食用胶因小麦粉品质不同对面团流变学特性的影响也不同,除添加0.25%的海藻酸钠外,其他添加量的3种食用胶均可降低特一粉的面团吸水率,提高上白粉的吸水率。研究认为,海藻酸钠、黄原胶、卡拉胶可显著改善小麦粉的面团流变学特性,增强面团筋力。     

燕麦粉对强筋面粉品质特性及其面包品质的影响

面包逐渐成为中国人营养早餐的选择,但面包中膳食纤维含量较低。燕麦是一种食疗兼备的特色杂粮作物,富含膳食纤维。为拓宽燕麦的应用范围、提高面包的营养价值,以优质强筋小麦品种藁优2018和燕麦粉为材料,研究了燕麦粉对小麦面粉面团流变学特性及淀粉糊化特性的影响,并进行了燕麦面包实验室制作和质构分析。结果表明,随着燕麦粉添加比例的增加,面团吸水率逐渐增加,面团稳定时间和粉质质量指数先减小后增加;面团拉伸能量、拉伸长度、拉伸阻力、最大拉伸阻力均逐渐减小。说明燕麦粉对面团拉伸特性各参数均有弱化作用。在藁优2018小麦面粉中添加10%的燕麦粉,既能保证面包的感官品质,又能满足面包营养最大化。     

大豆膳食纤维对面团流变学特性及面制品品质影响的研究进展

随着人们对均衡膳食和高品质面制品需求的不断提高,通过添加大豆膳食纤维改良面团流变学特性,进而在一定程度上改良面制品品质成为新的研究热点.该文综述了近年来添加大豆膳食纤维改善面团流变学特性及面制品品质方面的研究进展.同时,归纳了大豆膳食纤维改善面团流变学特性及面制品品质的作用机理,为加工富含大豆膳食纤维的高品质面团及面制...     

超绿活性茶粉对不同筋度小麦粉面团流变学特性的影响

将超绿活性茶粉(Ultra-green Active Tea Powder,UGA-TP)添加到低筋粉、中筋粉、高筋粉中,加水形成小麦粉面团,利用粉质仪、拉伸仪测定含超绿活性茶粉的不同筋度小麦粉面团流变学特性。研究结果表明:超绿活性茶粉的添加可以提高小麦粉面团吸水率、面团形成时间和面团稳定时间,含茶低筋粉和中筋粉面团与空白面团样品相比,在醒发时间45、90、135 min时,拉伸曲线面积、拉伸阻力、拉伸比例显著增加,延伸度显著下降;其中超绿活性茶粉对低筋粉的影响最大,主要表现为添加超绿活性茶粉后,低筋粉面团吸水率显著增大2.9%,面团形成时间显著增加8.7 min,面团稳定时间显著增加19.2 min;以醒发45 min为例,拉伸曲线面积从76 cm2显著增大到134 cm2,拉伸阻力从300 BU显著增大到645 BU,拉伸比例从2.1显著增大到4.9,延伸度从142显著下降到131。综合得出超绿活性茶粉的添加对不同筋度小麦粉的加工性能均有改善效果,其中对低筋小麦粉改善的效果最大。     

超绿活性茶粉对小麦粉面团烘焙加工特性的影响研究

本文基于超绿活性茶粉不同添加量,展开研究其对小麦粉面团面筋强度、糊化特性以及玻璃态相变温度等烘焙加工特性的影响。试验结果表明：随着超绿活性茶粉添加量的增加,小麦粉面团抗拉伸阻力呈现较显著的递减趋势,主要糊化特征参数峰值粘度、衰减值、最终粘度和回生值呈现下降趋势,而玻璃态相变温度的变化呈现无规律化。     

富含11S大豆分离蛋白中试规模提取及其在冰淇淋和面制品中的应用

11S球蛋白是大豆蛋白中的主要成分,具有优良的加工特性.本文报道了中试水平上提取富含11S组分大豆分离蛋白技术,及其添加到冰淇淋和面粉中对产品特性的影响.试验结果表明,中试生产所得到的富含11S组分分离蛋白中,11S组分的含量达81.3%(占总蛋白含量).添加6%左右的富含11S组分大豆分离蛋白代替冰淇淋原料中的脱脂奶粉可提高冰淇淋的膨胀率,并具有良好的风味;在中等筋度的小麦粉中添加3%的富含11S组分分离蛋白,可提高面团吸水率、面团形成时间和面团稳定性,粉质评价值得到提高.     

维生素C对面包烘焙品质及面团特性的影响

为研究添加维生素C对不同筋力小麦粉面包烘焙品质的改良效果,以师栾02-1、石优17、矮抗58和济麦22四个不同筋力小麦品种的面粉为材料,研究了维生素C对面包烘焙特性及面团流变性特性的影响。结果表明,添加维生素C对强筋品种师栾02-1和中筋品种矮抗58的面包体积有显著改良作用,而对4个品种的面包外观、面包芯色泽、面包芯质地和面包芯纹理结构均没有影响。添加维生素C对面团的弱化度和最大拉伸阻力等流变学特性的改良作用也因小麦品种而异,而且改良作用有限,不能改变小麦粉本身的加工属性。     

茶叶粉对小麦面粉流变学及糊化特性的影响

为进一步提高茶叶在食品工业中的应用范围,以小麦西农538(中筋)为供试材料,分别添加0、2%、4%、6%、8%和10%的绿茶、红茶和黑茶3类茶叶粉于面粉中,并对其进行面团流变学特性及糊化特性分析。结果表明,3类茶叶粉均可显著改善面团的流变学特性及糊化特性。随着茶叶粉添加量的增加,面团吸水率均显著增大;添加2%~10%的绿茶粉及6%~10%的黑茶粉,面团的形成时间和稳定时间均显著提高,弱化度均显著降低。添加6%的绿茶粉时,面团的拉伸能量和最大拉伸阻力增幅均达到最大值,延伸度出现小幅度升高的拐点;添加4%的红茶粉,面团的拉伸面积显著增大,继续增加添加量则变化不明显;黑茶和红茶粉添加量分别大于4%和6%时,面团延伸度均显著降低。面粉中添加适量的茶叶粉可改善面粉的品质,绿茶粉的添加对面团网络结构形成速度和面团筋力的改良效果大于红茶粉和黑茶粉。面粉糊化的峰值黏度、低谷黏度、最终黏度、峰值时间、回生值随着茶叶粉添加量的增大均呈不同幅度的降低趋势;3类茶叶粉对面粉糊化的热稳定性具有不同程度的改善作用。     

大豆膳食纤维在面包中的应用

文章研究了大豆膳食纤维在面包中的应用。添加大豆膳食纤维后,面粉的粉质特性发生了明显的改变:面团形成时间和稳定时间随着大豆膳食纤维添加量的增加先升高再降低,弱化度则是先下降再升高,而吸水率则是随着膳食纤维的添加量的增加一直升高;在面包中添加大豆膳食纤维在保持口感的基础上提高面包出品率,通过正交实验确定最佳配方为:面粉213.4 g、水119.8 g、白砂糖20 g、鸡蛋1个、黄油20 g、大豆膳食纤维6.6 g、食盐2 g、酵母2 g、面包改良剂3.3 g、谷朊粉2.2 g,能够提高7%左右出品率,并且使面包保持良好的口感和风味。     

叶面喷施糖和氮对春小麦籽粒蛋白质含量及面粉加工品质的影响

为了探究花后养分供应对小麦加工品质的效应,选用不同筋力的春小麦品种克旱19(KH19)和龙麦33(LM33)为试验材料,通过齐穗后叶面喷施5%蔗糖和2%尿素,分析籽粒建成期籽粒中氮含量的变化、成熟期籽粒蛋白质及其各组分含量的变化与面粉加工品质(面筋含量、粉质特性和拉伸特性)的关系。结果表明,与对照(CK)相比,蔗糖处理后小麦籽粒含氮量升高幅度最大;蔗糖和尿素的喷施均增加了小麦籽粒总蛋白质含量(KH19:8.34%,6.67%; LM33:9.36%,6.66%)及蛋白质各组分含量,蔗糖处理后小麦籽粒中蛋白质含量比尿素处理的高1%～3%;蔗糖处理后麦谷蛋白+醇溶蛋白含量在总蛋白中的比例下降1～5%;蔗糖和尿素处理均提高了小麦籽粒的干、湿面筋含量、面粉吸水率和面团形成时间;尿素处理延长了面团断裂时间与面团稳定时间,而蔗糖处理缩短了面团断裂时间与面团稳定时间;尿素处理增加了小麦拉伸能量(拉伸面积),而蔗糖处理降低了拉伸能量,尿素处理较蔗糖处理对面团的拉伸比值影响更大。     

Effect of stir-frying on oat milling and pasting properties and rheological properties of oat flour

Stir-frying, similar to roasting, is a key step for oat milling process in China. The oat flour milling yield of Bayou No.2 and Bayou No.8 and their corresponding flour quality were investigated under different processing conditions (160 °C, for 0, 10, 20, 30 and 40 min). Results showed that oat flour milling yield was increased after stir-frying, Bayou No.2 and Bayou No.8 reached the highest yield after a 10 min and 20 min of stir-frying, which were 45.40% and 52.96%, respectively. With the increasing of stir-frying time, the gelatinization degree and the particle size of oat flour gradually increased, while their angle of repose and L* values were reduced. RVA studies showed that the stir-fried oat flour exhibited lower peak, trough, breakdown and setback viscosities compared to not stir-fried oat flour, indicating that stir-fried oat flour formed a more stable network structure and stir-frying induced an inhibitory effect on the retrogradation of oat flour paste. Rheological analysis suggested that the low tanδ of stir-fried oat flour than that of not stir-fried oat flour, revealing that the stir-fried oat flour paste exhibited more elastic but less viscous behavior.     

Comparison of quality of refined and whole wheat tortillas

The use of whole wheat flour instead of refined flour significantly improves the nutritional profile of flour tortillas. However, whole and refined flours differ in properties and in how they process, thus needing process modifications to get the desired product quality. To understand these differences, refined and whole wheat flours, dough and tortillas were evaluated and compared for physical and rheological properties. Overall, whole wheat flour required more water (59% of flour weight) than refined wheat (53%) to make machineable dough. Refined flour doughs were more extensible and softer than whole wheat flour doughs, thus easier to process. Whole wheat flour tortillas were larger, thinner and less opaque than refined flour tortillas. In general, refined wheat tortillas were more shelf-stable than whole wheat tortillas. Smaller particle size and less fiber in the refined wheat flour mainly contributed to the observed differences. Among the whole wheat samples, tortillas from strong flours had excellent shelf-stability, which must be considered when whole wheat tortillas are processed. This will minimize the need to add vital wheat gluten or other dough strengtheners.     

Effects of potato/wheat flours ratio on mixing properties of dough and quality of noodles

The effects of potato flour/wheat flour (PF/WF) ratio on the mixing properties of dough and the quality of noodles were investigated. Substitution of wheat flour with potato flour caused the increases in the water absorption and the protein weakening value (C1-C2) of formulated flours, as well as the decrease in the corresponding dough mixing parameters including dough development time (DDT), dough stable time (DST), initial mixing time (C2), maximum torque during heating (C3), minimum torque of hot paste (C4) and the amount of retrogradation (C5-C4), indicating that the addition of PF weakened dough strength but improved degradation resistance. The textural, cooking, sensory characteristics and microstructure of noodle samples were evaluated. The results indicate that adhesiveness, springiness, broken ratio and cooking lose increased progressively with increasing PF content while the score of sensory evaluation continued to decrease. However, hardness, cooking yield and optimum cooked time for the samples of PF content range from 10% to 20% showed a distinctive variation. Environmental scanning electron microscopy (ESEM) confirmed changes in noodle microstructure as PF addition affected gluten network development. In general, noodles with PF content below 40% were acceptable.     

Wheat flour non-starch polysaccharides and their effect on dough rheological properties

Wheat (Triticum aestivum L.) flour is able to form dough with unique rheological properties that allow bread making. It is well known that wheat protein content affects dough rheological properties, but there is not enough evidence about the role of other minor flour constituents. One such minor constituent is non-starch flour polysaccharides, which are mainly pentosans formed by a xylopyranosyl linear chain branched with arabinofuranosyl residues. Their spatial distribution and branching pattern can affect their relationship with gluten forming proteins and thus influence their functional properties, the dough rheological properties, and thereby the flour baking quality. In this study the content and structural characteristics of non-starch polysaccharides were investigated, as well as their influence on some dough physicochemical parameters. Five different wheat flours samples milled from Uruguayan wheat varieties with diverse rheological and breadmaking properties were used in this study. Water soluble flour polysaccharides were extracted and the amount of pentosans was determined by the orcinol-HCl method. The pentoses composition was determined before and after acidic hydrolysis of the water soluble polysaccharide fractions by GC. No free pentoses were detected in any of the assayed flour samples, so the pentoses composition found in the hydrolyzed samples was attributed to the non-starch water soluble polysaccharides. Water unextractable non-starch polysaccharides were determined by difference between the total and the soluble non-starch polysaccharides flour content.An improved method for the quantification of water extractable and non-extractable non-starch polysaccharides, using baker's yeast, was developed. Using this method, total and soluble non-starch polysaccharides content could reliably be determined both in whole flour and in pentosans enriched fractions. Free monosaccharide content was in the range from 0.03% to 0.06% (w/w), while the arabinose/xylose (Ara/Xyl) ratios varied from 0.8 to 1.4 in soluble non-starch polysaccharides and from 0.7 to 0.9 in total non-starch polysaccharides. The different Ara/Xyl ratios found for water extractable and unextractable arabinoxylans clearly indicates different substitution degrees in the polymers. Analysis of the dough rheological parameters in relation to the water soluble and non-soluble non-starch polysaccharides and the Ara/Xyl ratios from different wheat varieties was performed. A clear relation between some of these parameters could be inferred, since a direct relationship between total unextractable (AXi) content and resistance of dough to extension (P), as well an inverse relationship between the same parameter and dough extensibility (L) were observed. These results suggest that the flour non-starch polysaccharide content, as well the Ara/Xyl ratios may be used as additional parameters to estimate some of the wheat flours dough properties.     

Effect of the addition of extruded wheat flours on dough rheology and bread quality

Extruded wheat flours, due to their increased water absorption capacity, constitute an opportunity to increase bread output in bakery production. However extrusion may modify dough and bread characteristics. The aim of this study was to investigate the effect of the substitution of 5% of the wheat flour by extruded wheat flour (produced with different time-temperature extrusion treatments) on dough mixing, handling and fermentation behaviour and bread volume, shape, texture and colour. The RVA curves indicate that extrusion intensity increases with increasing temperature or water content. Water absorption capacity rises with increasing treatment intensity, but dough stability tends to decrease. Adding extruded flours decreases dough extensibility but increases tenacity and gas production. Differences in dough structure were observed on photomicrography, though there were no clear differences in bread quality. These results indicate that it is possible to obtain adequate dough and bread characteristics using dough with 5% extruded wheat flour.     

The effects of sodium reduction on the mechanical properties of doughs made from flours with a range of strengths using a mixograph

To devise strategies for meeting Health Canada's target for reduced-sodium bread production, relationships between dough formula (i.e., red spring wheat flour, salt (NaCl) and water content) and dough mechanical properties were examined. Mixograph energy to peak (ETP), peak height (PKH), and peak bandwidth (PBW) were used to define changes in the properties of doughs induced by sodium reduction. ETP measurements indicated that dough strength characteristics were less responsive to sodium reduction as water content was increased. ETP was a good indicator of the cultivar-dependent response of doughs to sodium reduction, with doughs made from stronger flours being more sensitive to sodium reduction. According to ETP results, sodium reduction led to a decrease in flour strength discrimination. Sodium reduction at NaCl contents below ~1.5% led to more obvious changes in dough mixing characteristics (indicated by the ratio of PBW to PKH). Mixograph analyses of dough tolerance to sodium reduction will guide wheat breeding programs to select cultivars suitable for reduced sodium breadmaking.