灌水频次对强筋小麦蛋白质组分含量、粒度分布和品质的影响

研究了不同灌水频次对强筋小麦(济麦20和藁城8901)的蛋白质组分含量、粒度分布、品质及产量的影响,结果表明:灌水次数在0~2范围内,济麦20和藁城8901的籽粒产量随灌水次数增加而增加,在灌水次数增加到3次时,籽粒产量较灌2水处理显著下降。随灌水次数增加,济麦20和藁城8901的SDS可溶性谷蛋白含量、SDS不溶性谷蛋白含量、醇溶蛋白含量、HMW-GS含量和LMW-GS含量均呈上升趋势,SDS不溶性谷蛋白聚合体的算数平均直径、面团品质(形成时间和稳定时间)和面包品质(体积和总评分)亦均呈上升趋势。相关分析表明,SDS可溶性谷蛋白含量与面团和面包品质达到显著正相关;SDS不溶性谷蛋白含量与面团和面包品质相关不显著,但其算数平均直径与面团和面包品质呈显著正相关。     

普通小麦胚乳蛋白质与面包烘烤品质关系的研究与利用注（I）蛋白质及其各组分的含量与烤品质的关系研究

普通小麦籽粒蛋白质的含量和质量是影响面包烘烤品质的决定性因素，本文综述了国内外学者对小麦蛋白质及其组分的含量和比例与烘烤品质的相关关系的研究，指出一定的粗蛋白含量是烘烤品质的基础，与粗蛋白含量相比，谷蛋白相对含量，尤其是高分子量谷蛋白亚基的相对含量及谷蛋白大聚合体的相对含量对面包烘烤品质的影响更大。     

普通小麦胚乳蛋白质与面包烘烤品质关系的研究与利用 (I)蛋白质及其各组分的含量与烘烤品质的关系研究

普通小麦籽粒蛋白质的含量和质量是影响面包烘烤品质的决定性因素。本文综述了国内外学者对小麦蛋白质及其组分的含量和比例与烘烤品质的相关关系的研究，指出一定的粗蛋白含量是烘烤品质的基础。与粗蛋白含量相比，谷蛋白的相对含量，尤其是高分子量谷蛋白亚基的相对含量及谷蛋白大聚合体的相对含量对面包烘烤品质的影响更大。     

小麦麸皮及面粉戊聚糖对面团特性及面包烘焙品质影响的比较研究

从小麦麸皮和面粉中分别制备水溶和水不溶戊聚糖，将其以0．5％的比例添加到面粉中，以研究其对面团特性及面包烘焙品质的影响。研究发现，小麦麸皮水溶戊聚糖对面团特性及面包烘焙品质的影响与面粉中的水溶戊聚糖相似，可明显改善面团特性及面包烘焙品质，主要体现在：可增加面团的粉质吸水量，增加面团的稳定时间，增加面包的体积，改善面包的内部质构；小麦麸皮水不溶戊聚糖对面团特性及面包烘焙品质有明显的弱化作用；而面粉中的水不溶戊聚糖则对面团特性及面包烘焙品质影响不大。     

小麦谷蛋白亚基的组成及含量与谷蛋白聚合体大分子的关系及其对面包烘焙品质的影响

含有高分子量谷蛋白亚基(HMW-GS)5 10的生物型小麦与2 12的生物型小麦相比，前者谷蛋白具有更大的分子量分布。高低分子量谷蛋白亚基的比例对于谷蛋白聚合体分子量的大小起着重要的作用，谷蛋白聚合体的体积越大，含有的高低分子量谷蛋白亚基的比例越高。SDS非可溶性谷蛋白含有较高比例的高低分子量谷蛋白亚基，并且其分子量要比可溶性谷蛋白聚合体的大。谷蛋白聚合体分子量分布的差异是不同小麦品种面包烘焙品质存在差异的重要因素。     

利用面粉理化指标预测面包体积

测定了大量样品的烘烤品质性状,用统计分析的方法研究面粉的理化指标对面包体积的预测效果,结果表明,在简单回归分析中,曲线回归的效果要好于直线回归;多元统计分析的结果表则表明,可以用谷蛋白大聚体含量,沉降值,面团形成时间和稳定时间来预测面粉的面包体积。     

冬小麦主要品质性状鉴定及其相关性研究

本文分析测定了国内２９个具有品质代表性冬小麦品种的１８项主要品质指标，对品质性状间的相关关系进行了较为全面的分析。结果表明，粗蛋白含量、清蛋白、醇溶蛋白、谷蛋白、干面筋、沉降值均与粉质仪性状和面包性状有着较为密切的关系，其中清蛋白对小麦品质有负的作用。粗蛋白含量与面包评分相关不显著。沉降值、干面筋、谷蛋白、清蛋白均与面包评分呈显著或极显著相关。蛋白组分比粗蛋白含量对小麦加工品质具有更重要的影响。沉降值与面包评价的关系极为密切，是预测国内小麦面包烘焙品质的重要指标。     

谷蛋白大聚体在小麦加工中的作用

谷蛋白大聚体(GMP)是小麦籽粒中最重要的蛋白质聚合体,不溶于1.5%SDS溶液,且分子质量较大,以颗粒形式存在,粒径范围为1~300μm;其含量和分子结构与食品加工品质密切相关,在面制食品加工中的作用远大于可溶性谷蛋白聚合体和单体蛋白。谷蛋白大聚体含量高的小麦品种,其面筋、面团的强度和弹性较大,面包烘烤品质较好,面条拉伸特性较好。谷蛋白大聚体在面团和面过程中会发生解聚,其含量、粒径和分子质量均降低;而在面团醒发过程中又会发生重聚。面条面坯形成过程中,谷蛋白大聚体含量的降低程度远低于传统面团,而凝胶强度的变化趋势则与传统面团相反。     

发酵方法对面包烘焙品质的影响

有发酵法、一次发酵法研究了发酵方法对面包烘焙品质的影响。试验结果表明,发酵次数越多,发酵时间越长,面包的烘焙品质越好,主要表现在面包体积更大、面包芯质地更加细腻柔软、面包芯纹理结构更好。其中,二次发酵法、三次发酵法和过夜种子面团法的得分比较接近。综合比较,在面包工业中,二次发酵法和过夜种子面团法更加适合生产面包。     

面粉麦谷蛋白大聚合体与扬州发酵包子面团品质相关性的研究

本研究以市售的7种小麦面粉为材料,对小麦面粉谷蛋白大聚合体与扬州发酵包子品质的关系进行研究。结果表明:蛋白质谷蛋白聚合体(GMP)含量的高低能够反映发酵面团的品质优劣,它与发酵包子面团品质呈正相关,测定GMP含量所需样品量少(5 g),效果优于其他品质指标,可以用来作为发酵包子品质预测的优先考虑。     

馒头加工过程中麦谷蛋白提取率变化研究

以3种小麦粉为原料,研究了在馒头加工过程中麦谷蛋白组分提取率的变化.结果表明:麦谷蛋白组分在馒头加工过程中均发生了有规律的变化.烟农19小麦样品SDS-可溶性麦谷蛋白提取率较低,残渣蛋白量多,很有可能是烟农19小麦样品通过-S-S-交联成的大分子麦谷蛋白含量高.3种小麦样品中GMP含量依次为烟农19＞豫麦47＞豫麦56.这说明GMP的含量和粒度分布是影响面粉烘焙品质性状的决定性因素.     

麦谷蛋白聚合体含量与小麦粉质量性状相关性研究

利用9个小麦高世代品系(F7),含118个株系为研究材料,研究了蛋白质组分及谷蛋白聚合体(GMP)含量与微量SDS沉降值及面筋指数的相关性.结果表明:清球蛋白含量与微量SDS沉降值无相关性,谷蛋白含量与微量SDS沉降值及面筋指数均呈极显著正相关;GMP含量、GMP/TPP、GMP/CP、GMP/SGP以及TPP/CP对微量SDS沉降值有极显著的正向作用,其中GMP的贡献最大;GMP含量、GMP/TPP、GMP/CP与面筋指数呈显著或极显著正相关,其中GMP/TPP与面筋指数的相关性最高.偏相关分析表明:微量SDS沉降值变异平方和的60.58%可由其与TPP%、GMP%和GMP/SGP的线性关系来说明;通径分析结果显示:GMP含量与微量SDS沉降值的相关性主要是由其直接效应提供,GMP含量是影响微量SDS沉降值的第一因素.研究结果指出,西南麦区小麦品质改良中GMP含量,面筋指数可作为优质面条、馒头小麦的早代选择指标.     

谷朊粉对面包基础粉品质特性的影响

探讨不同添加量的谷朊粉对面包基础粉蛋白质的品质、流变特性及面包烘焙品质的影响。结果表明:谷朊粉可以明显增加面包基础粉的湿面筋含量、沉淀值和蛋白质含量,强化其流变学特性,有效改善面包烘焙品质,增大面包比容和高径比并改善其弹性和硬度。当谷朊粉添加量为10%时,面包烘焙品质最好。     

Effect of Flour Quality, Ascorbic Acid, and DATEM on Dough Rheological Parameters and Hearth Loaves Characteristics

ABSTRACT: The effects of protein quality, protein content, ascorbic acid, diacetyl tartaric acid ester of monoglyc-erides (DATEM), and their interactions on dough rheology and hearth bread properties were studied by size-exclusion fast protein liquid chromatography, Kieffer Dough & Gluten Extensibility Rig, and small-scale baking of hearth loaves. The effect of protein content was either positive or negative on hearth loaf characteristics, form ratio, and area, depending on the amount of the largest glutenin polymers in the flour. Ascorbic acid brought out the potential in the wheat flour known as protein quality. Ascorbic acid and DATEM strengthened the doughs and improved hearth bread characteristics.     

Influence of genotype and protein content on the baking quality of hearth bread

The relationships between protein content and quality and the loaf characteristics of hearth breads made from the respective flours were investigated for 20 wheat genotypes, comprising both commercially grown cultivars and advanced breeding lines, grown in 1997 and 1998. In both years the average protein content was increased by increasing the level of nitrogenous fertiliser application, this effect being more pronounced in 1997 than in 1998. Grain samples were milled and evaluated for endosperm hardness, protein content, SDS sedimentation volume, mixing properties and baking quality determined by a hearth bread baking test using optimal mixing and fixed proving time. When producing hearth bread, both the form (height/width) ratio and loaf volume are critical external characteristics. Genotype differences, mainly due to differences in protein quality, were more important for both form ratio and loaf volume than differences in protein content. The dough development time of the Farinograph, operated at high speed (126 rev min^?1), was the best indicator of heart bread baking quality, giving high positive correlations to both the volume (r = 0.89) and form ratio of the loaf (r = 0.90). Climatic differences between the two years, in particular temperature during ripening, also affected the quality parameters studied. Copyright © 2004 Society of Chemical Industry     

Effect of green plantain flour addition to gluten‐free bread on functional bread properties and resistant starch content

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.     

Improving wheat for bread and tortilla production by manipulating glutenin‐to‐gliadin ratio

Gluten, starch, water soluble material, and glutenin‐rich and gliadin‐rich proteins were extracted from three Canadian wheat cultivars representing the Canada Western Red Spring (CWRS) (cv Roblin), Canada Western Extra Strong (CWES) (cv Glenlea) and Canada Prairie Spring (CPS) (cv AC Crystal) classes having glutenin‐to‐gliadin (Glu:Gli) ratios of 0.70, 0.75 and 0.85 respectively, all giving the same high‐molecular‐weight glutenin subunit score (Glu‐1 score) of 10. The resulting fractions were reconstituted to produce 18 mixtures of flour components, representing all combinations of Glu:Gli ratio and protein content observed in the original three flours. Dough rheological properties and baking (bread and tortilla) performance were determined using small‐scale techniques. Within any of the cultivars, increasing the Glu:Gli ratio in a reconstituted dough system had significant effects on dough and end‐use properties, causing increases in mixograph development time (MDT), maximum resistance (Rmax), pan bread loaf volume, tortilla dough maximum resistance and cooked tortilla puncture force. The CWRS wheat Roblin, proved to be best suited for pan bread at higher protein content and higher Glu:Gli ratio, and also produced a high protein tortilla of large diameter at a Glu:Gli ratio of 0.70. The CPS flour, AC Crystal, was good for making tortillas at protein contents of 110–130 g kg⁻¹ and at its original ratio of 0.85. The CWES wheat Glenlea, did not perform as well in bread or tortilla‐making but in its role as a blending wheat, altering the Glu:Gli ratio of Glenlea to 0.70 may have an advantage by lowering mixing time without compromising baking properties. Manipulating the Glu:Gli ratio may make a wheat cultivar suitable for a particular end‐product. For the Department of Agriculture and Agri‐Food, Government of Canada, © Minister of Public Works and Government Services Canada 2005. Published for SCI by John Wiley & Sons, Ltd.     

发酵时间对馒头品质及面筋蛋白结构的影响

利用体积仪、质构仪和傅里叶变换红外光谱分别测定馒头比容、质构特性与面筋蛋白二级结构,探究发酵时间对馒头品质及面筋蛋白结构的影响。结果表明:馒头中醇溶蛋白与麦谷蛋白中β-折叠含量均为最高。随着发酵时间的不断延长,醇溶蛋白中β-折叠、α-螺旋相对含量无显著性变化,无规则卷曲逐渐减少,而β-转角则逐渐增加;羟基吸收带逐渐增强,醇溶蛋白的水合作用增强。麦谷蛋白中α-螺旋与无规则卷曲相对含量变化不大,β-折叠相对含量先上升后下降,而β-转角相对含量则是先下降后上升;羟基带强度逐渐减弱;当发酵时间延长到80 min时,麦谷蛋白红外光谱位于1 082 cm~(-1)与1 155 cm~(-1)处的峰消失,可能是蛋白质环状结构的C—C振动减弱。     

Hearth bread baking quality of durum wheat varying in protein composition and physical dough properties

Thirty durum wheat genotypes from ten countries of origin were grown in field plots for two consecutive years. Three of the genotypes were γ‐gliadin 42 types and the remainder were γ‐gliadin 45 types. Among the γ‐gliadin 45 types, six high‐molecular‐weight glutenin subunit (HMW‐GS) patterns were identified: 6 + 8, 7 + 8, 7 + 16, 14 + 15, 20 and 2*, 20. All the γ‐gliadin 42 genotypes contained low amounts of unextractable polymeric protein (UPP) and exhibited low gluten index values and weak gluten properties. The γ‐gliadin 45 genotypes exhibited a wide range of UPP, gluten index and dough strength. HMW‐GS 20 genotypes were generally weak, whereas HMW‐GS 6 + 8 and 7 + 8 genotypes were generally strong. When baked by a lean formulation, long‐fermentation straight‐dough hearth bread process, the durum wheat genotypes exhibited a wide range of baking quality. Loaf volume and bread attributes were strongly correlated with UPP and gluten index. Some of the genotypes exhibited bread attributes and loaf volume equal or slightly superior to those of a high‐quality bread wheat flour. However, even the strongest durum wheat genotypes exhibited inferior fermentation tolerance to the bread wheat flour, as seen by a requirement for lower baking absorption during dough handling and more fragile dough properties when entering the oven. Among the HMW‐GS groups, HMW‐GS 7 + 8 and 6 + 8 exhibited the best and HMW‐GS 20 the poorest baking quality. Farinograph, alveograph and small‐scale extensigraph properties demonstrated that a combination of dough elasticity and extensibility was needed for superior durum wheat baking performance. Copyright © 2007 Society of Chemical Industry     

Investigations into the use of near infrared reflectance spectroscopy for the quality assessment of wheat with respect to its potential for bread baking

The possible use of near infrared (n.i.r.) reflectance spectroscopy for the prediction of the bread baking quality of wheat has been investigated. A number of UK wheat samples were studied using a monochromator system which enabled reflectance data between 1100 and 2500 nm to be measured. These data were correlated with protein content, α-amylase as measured by Falling Number, and protein quality as measured by SDS sedimentation volume, with the result that only protein content was capable of satisfactory calibration against n.i.r. Furthermore, no improvements to the wavelengths currently available in filter instruments could be found for the measurement of protein in wheat. It is therefore concluded that for UK wheat at least, n.i.r. spectroscopy cannot provide a measurement of bread baking quality of wheat beyond that which may be predicted from protein content.