南方馒头加工工艺优化

为获得制作南方馒头的最适工艺参数,探究了和面时间、醒发时间、醒发温度、醒发湿度、压面次数、辊轴宽度对南方馒头比容、色度L值、硬度、弹性、黏着性及综合品质得分的影响,以南方馒头品质综合得分为评价指标,通过单因素及正交试验优化得出南方馒头最佳工艺条件为:和面时间3 min,醒发湿度80％,醒发时间30 min,醒发温度40℃,压面12次,辊轴宽度5.5 cm.在此条件下,南方馒头的品质综合得分为3.26.     

Screening drought-tolerant genotypes in bread wheat (Triticum aestivum L.) using different multivariate methods

Wheat (Triticum aestivum L.) is one of the most widely cultivated crops in rainfed areas of Iran, where drought is the main limiting factor on yield. The object of this study was the identification of drought-tolerant genotypes in bread wheat. Forty bread wheat genotypes were tested in separate experiments under drought stress and normal conditions in two years (2009–2010 and 2010–2011). Nine drought-tolerance/susceptibility indices including stress susceptibility index (SSI), mean productivity (MP), tolerance (TOL), stress tolerance index (STI), geometric mean productivity (GMP), yield index (YI), yield stability index (YSI), linear regression coefficient (β) and drought response index (DRI) were determined. Simultanously applied factor analysis used two factors instead of nine indices in this study. Mahdavi was recognized as the most drought-tolerant genotype in both years based on factor analysis. In this study an equation was developed for estimating the Stress Tolerance Score (STS). The results of the equation were identical to those of factor analysis in both years. The equation was much easier to use than factor analysis and is suggested as a screening tool for the identification of drought-tolerant genotypes. In this study, Mahdavi was the most drought-tolerant genotype also corresponding to this equation.     

Selected nutritional,physical and sensory characteristics of pan and flat breads prepared from composite flours containing fababean

Composite flour blends containing wheat (W), fababean (F), cottonseed and sesame flours were formulated to provide the FAO/WHO/UNU protein requirements for the 2–5 year old child, and evaluated in pan and flat bread applications. Water absorption of composite flour doughs was up to 35% greater than the control but gluten strength and slurry viscosities were markedly reduced. Loaf volume and specific volume of pan breads prepared from composite flours were 25–60% less than that of the control bread but flat breads tolerated the protein supplements extremely well. The W/F flat bread, containing 27% of fababean flour, received acceptable taste, texture and colour scores and was only slightly inferior to the control in puffing and layer separation. Additions of cottonseed or sesame flours to the W/F blend failed to improve sensory properties of the flat breads.     

The apparent digestibility of energy,nitrogen and fibre and the biological value of protein in low- and high-fibre wheat breads

Sixteen 15 kg liveweight entire-male pigs were given either a low-fibre (1.21 g/100 g Neutral detergent fibre, NDF) or a high-fibre (6.38 g 100 g, NDF) wheat bread as their sole source of dietary protein, in a conventional 21-day metabolism study. A glucose/oil supplement which was assumed to be completely absorbed was given with the bread to ensure a high ratio of dietary energy to protein, to allow measurement of biological value (BV). The apparent faecal digestibility of gross energy was significantly (p<0.001) lower (7.4% units) for pigs given the high-fibre bread as was the apparent digestibility of NDF (24% units lower). The apparent faecal digestibility of total nitrogen was also significantly (p<0.001) lower for the animals fed the high-fibre bread, but there were no significant differences between the breads for the BV of their protein. The overall mean BV for the breads was 46%. The results indicate a significantly lower digestibility of nutrients and gross energy in breads containing appreciable quantities of wheat bran fibre.     

Functional Properties of Wheat Gliadins. II. Effects on Dynamic Rheological Properties of Wheat Gluten

The effects of addition of purified total gliadin and its subgroups (α-, β-, γ- and ω-gliadins) on the dynamic rheology of gluten were investigated. The frequency sweeps of gluten with added α-, β-, γ- and ω2-gliadins showed unexpected increases in the magnitude of G′ and G′′, suggesting stiffening of the native gluten. Conversely, a reduction in the magnitude of G′ and G′′ occurred upon addition of the total gliadin fraction and the ω1-gliadin, implying softening of the gluten. Addition of individual gliadin fractions increased the values of slope log G′ vs log frequency, suggesting increased concentrations of uncrossed-linked material compared with the native gluten. There were significant differences in the slope values for individual gliadin fractions. The increasing order of slopes for different gliadins was: β- >γ- >α- =ω1>ω2, indicating that glutens containing ω- and α- gliadins are relatively less crossed-linked than those containing β- and γ-gliadins. The dynamic moduli, G′ and G′′, of cv. Hereward gluten showed significant positive relationships with Mixograph parameter peak dough resistance (PDR), and loaf volume for gliadin subgroups added to cv. Hereward flour.     

高产优质面包用春小麦新品种甘春20号配麦特性研究

为了了解高产、优质、面包用春小麦新品种甘春 2 0号的配麦特性 ,为面粉加工企业通过配麦技术生产成本较低的专用面粉提供科学依据 ,将甘春 2 0号 (蛋白质和湿、干面筋含量依次为 12 .5 %、34.8%、11.8% ,属强筋小麦 )与宁春 18号 (蛋白质和湿、干面筋含量依次为 10 .9%、2 8.6 %、10 .5 % ,属中筋小麦 )和高台麦 (蛋白质和湿、干面筋含量依次为 9.3%、2 5 .2 %、8.7% ,属弱筋小麦 )的籽粒按不同比例 (重量比 )进行搭配后 ,测定蛋白质品质、面团流变学特性和面包、馒头、面条加工品质。结果表明 ,在甘春 2 0号中搭配 10 %～ 4 0 %的宁春 18号或 10 %的高台麦后 ,蛋白质和湿、干面筋含量仍然较高 ,依次在 11.8%、2 9.7%、10 .3%以上 ,并且仍具有较高的面包评分 (>87.2分 ) ,同时可显著改善宁春 18号和高台麦的面条品质 (搭配后的面条评分在 86 .7分以上 ,分别比宁春 18号和高台麦的面条评分高出 9.3和 2 0 .0分以上 ) ;在甘春 2 0号中搭配 10 %～ 30 %的宁春 18号 ,可显著改善甘春 2 0号和宁春 18号的馒头品质 (搭配后的馒头评分在 88.5分以上 ,分别比甘春 2 0号和宁春 18号的馒头评分高出 5 .2和 2 .7分以上 )。甘春 2 0号为面包、馒头、面条兼用型品种 ,宁春 18号是优质馒头小麦 ,而高台麦只能作为搭配     

Yeast breads containing oils varied in fatty acid composition: Effects on sensory panel acceptability

Choice of the shortening ingredient in bread products has functionality effects and health implications. Little information is available on effects of various shortening ingredients on palatability and acceptability. The objective of the current study was to compare the acceptability of yeast-leavened wheat breads containing shortenings containing predominantly saturated fatty acids (coconut oil), monounsaturated fatty acids (canola oil) or unsaturated fatty acids (unhydrogenated soybean oil). Breads were prepared using a standardized formula and method. These were evaluated by a 16-member, semi-trained panel for color, flavor, texture, tenderness and overall acceptability using a seven-point hedonic scale. No significant differences in color and texture were defined; however, canola oil bread was judged significantly superior to soybean oil bread in flavor, and both of these breads were found to be significantly superior to coconut oil bread in flavor, tenderness, and overall acceptability.     

四季营养面包的研制

为了提高面包的营养价值,改善口感和风味,在确定其制作工艺的基础上,融合四时养生与中医药膳食养学的传统养生理论,在普通面包的基础上（配方：高筋面粉500 g、海藻糖50 g、砂糖50 g、奶粉5 g、酵母5 g、海藻酸钠1.5 g、鸡蛋1颗、水250 g）,选用有春、夏、秋、冬为元素的16种食材来研发制作了一款系列形式的营养面包。通过食材的比例用量进行单因素试验和正交试验,以感官评分为指标,确定以下配方（面粉质量为100%）：春季营养面包,糯米∶燕麦（体积比）=2∶1,菊花120朵/500 g水,菠菜泥5%;夏季营养面包,红小豆∶红米（体积比）=1∶2,山楂18%,胡萝卜碎3%;秋季营养面包,山药∶银耳（质量比）=1∶1,百合1%,白果0.4%;冬季营养面包,黑豆∶核桃仁（质量比）=6∶1,黑芝麻8%,枸杞子12%。根据该工艺制作的面包外型饱满,口感良好,营养丰富,是老少皆宜的健康食品。     

Effect of hydrothermaled bran on physicochemical, rheological and microstructural characteristics of Sangak bread

Increased consumption of whole grain products has been associated with decreased risk of health problems such as cardiovascular disease, diabetes and obesity. Phytate however, has always been a matter of concern, since it chelates minerals such as iron. Sangak is very popular Iranian flat bread invented five hundred years ago, made from 95% extraction flour. The bread is fermented but usually fermentation is not able to remove all phytate from the dough. In this study flours were first debranned; resulting bran was subjected to a hydrothermal process. The hydrothermaled (HT) brans were then incorporated in the Sangak flour. In the next step, physicochemical, rheological and microstructural characteristics of Sangak flour and dough prepared from two Iranian wheat varieties, Tajan and Back Cross of Roshan were investigated. Results indicated a reduction in phytate up to 55% in the samples. The resulting dough containing HT bran showed a higher development time and valorimetric value and was more stable than doughs made with normal bran. Dough made with HT bran showed a kind of protein matrix in which proteins and starch granules are oriented in a more non-ordered structure.     

小麦蛋白质和淀粉性状与面包品质关系研究进展

蛋白质和淀粉是影响面包品质的主要因素。蛋白质的含量和质量,直链淀粉、支链淀粉比例以及破损淀粉含量都对面粉烘培品质有重要影响。本文综述了国内外对蛋白质和淀粉特性与面包品质关系的研究进展,并指出了下一步研究的重点。