Effect of Different Extrusion Parameters on Dietary Fiber in Wheat Bran and Rye Bran

Wheat bran and rye bran are mostly used as animal feed today, but their high content of dietary fiber and bioactive components are beneficial to human health. Increased use of bran as food raw material could therefore be desirable. However, bran mainly contains unextractable dietary fiber and deteriorates the sensory properties of products. Processing by extrusion could increase the extractability of dietary fiber and increase the sensory qualities of bran products. Wheat bran and rye bran were therefore extruded at different levels of moisture content, screw speed and temperature, in order to find the optimal setting for increased extractability of dietary fiber and positive sensory properties. A water content of 24% for wheat bran and 30% for rye bran, a screw speed of 400 rpm, and a temperature of 130 °C resulted in the highest extractability of total dietary fiber and arabinoxylan. Arabinoxylan extractability increased from 5.8% in wheat bran to 9.0% in extruded wheat bran at those settings, and from 14.6% to 19.2% for rye bran. Total contents of dietary fiber and arabinoxylan were not affected by extrusion. Content of β‐glucan was also maintained during extrusion, while its molecular weight decreased slightly and extractability increased slightly. Extrusion at these settings is therefore a suitable process for increasing the use of wheat bran and rye bran as a food raw material.     

维生素C对面团特性影响研究

通过研究Vc对面团特性影响表明,面粉中添加Vc能增加面团吸水率和形成时间,降低面团弱化度,增加面团拉伸面积、拉伸阻力和拉伸比值,降低面团延伸性;其最适添加范围为120～160ppm.     

Influence of partial substitution of wheat flour with vetch (Lathyrus sativus L) flour on quality characteristics of doughnuts

Partial substitution of wheat flour (Triticum aestivum) with vetch flour (Lathyrus sativus L) at the levels of 5, 10, 15 and 20 g/100 g was carried out to determine its influence on physico-chemical, rheological, nutritional and sensory characteristics of composite flour doughnuts. Commercial wheat variety, Inqlab-91 was found suitable for the preparation of doughnuts. Sensory and objective evaluations (weight, volume and specific volume) of doughnuts were carried out to evaluate the acceptability of doughnuts. Protein, lysine and trypsin inhibitor contents increased significantly (P<0.05) from 12.10 to 13.84 g/100 g, 2.46-3.58 g/100 g protein and 173 to 187 TIU/g on increasing the level of vetch flour from 0 to 15 g/100 g in the doughnuts, respectively. In vitro protein digestibility of doughnuts was also found to increase (71.8-76.3 g/100 g). It was inferred that doughnuts supplemented with vetch flour up to the level of 15 g/100 g were sensorily acceptable.     

Sourdough fermentation of wheat fractions rich in fibres before their use in processed food

Fibre‐rich fractions of wheat are an important source of minerals but also contain considerable amounts of phytic acid, known to impair mineral absorption. This study explores the efficiency of wheat bran sourdough fermentation on phytate hydrolysis and mineral solubility, in comparison with whole‐wheat flour. In vitro trials were performed to assess the consequences of the addition of calcium carbonate (CaCO₃), an alkalinising salt, on phytic acid breakdown and mineral bioavailability during sourdough fermentation. Sourdough fermentation was found effective for solubilising minerals in whole‐wheat flours but was less effective with bran. In addition, sourdough acidity was blunted by the addition of CaCO₃, whereas degradation of phytic acid remained effective. Despite extensive breakdown of phytic acid (almost 70%), the addition of calcium exerted a very negative effect on zinc solubility. In conclusion, a pre‐fermentation process of whole cereals or bran, in suitable conditions of hydration, allows degradation of the major part of phytic acid and optimal mineral bioavailability. Copyright © 2007 Society of Chemical Industry     

Fatty acids,mineral composition ond functional (bread and chapati) properties of high protein and high lysine barley lines

Six barley lines derived from corsses involving Hiproly (SV 73608×Mona⁵) and Riso 1508 with higher yield recipients V 43-42 and V 5681, along with the four parents, were analyzed for faty acids and mineral composition. Dough properties, bread and chapaties were charcterized by blending barley line (B82503) at 2.5-25% with bread wheat flour (pak 81). Fatty acid contents were myristic acid, 0.60-1.16%; palmitic acid, 16.68-20.84%; stearic acid, 1.30-3.33% and degree of unsaturation 1.40-1.50%. The derived lines contained similar amounts of essential fatty acids. Significant variation for magnesium, copper, zinc, phosphorus and potassium was observed but overlapped among the lines and parents. The calciu, iron, and manganese showed non-significant differences among lines and parents. Blending up to 10% barley flour with bread wheat flour gave farinograph characteristics comparable to those of pure wheat flour, but increasing the proportion of barley beyond this decreased the mix time and dough stability. Breadbaking tests verfied that up to 10% barley could be mixed with wheat without adversely affecting loaf volume and other quality attributes. For chapati making up to 20% barley could be blended into the wheat, yet yield acceptable quality.     

用国产优质麦生产优质的中国主食专用粉（I）——兼论合理使用面粉处理剂

生产优质的中国主食专用粉需要优质麦,本着重对当前国产小麦的品质状况,以及利用国产小麦生产中国主食专用粉的主要技术措施,后处理技术进行了详细的探讨。     

八辊磨粉机研磨效果的研究

在实际生产中对八辊磨粉机1皮,2皮进行研磨试验,通过流量的变化及1皮与2皮轧距的组合,测得不同工况下的研磨剥剥刮率,取粉率,耗用电流,研磨物料粒度分布及分级的物料的灰分,研究在原料,磨粉机技术参数相对稳定的条件下,流量,轧距对研磨效果的影响,为八辊粉机的使用和操作,及小麦制粉工艺设计提供依据。     

Composite wheat–germinated brown rice flours: selected physicochemical properties and bread application

Selected physicochemical properties of composite [wheat/germinated brown rice (GBRF)/germinated glutinous brown rice (GGNBRF)] flours at 100:0:0 (control), 70:30:0, 60:30:10, 60:40:0 and 50:40:10 (%) were evaluated. Germination (steeping at pH 3 for 24 h at 35 °C) increased free gamma‐aminobutyric acid from 2.11 to 32.7 and 2.41 to 30.69 mg per 100 g flour for GBRF and GGNBRF, respectively. The 60:30:10 and 50:40:10 composite flours exhibited the lower peak viscosity (70.42 and 68.54 RVU, respectively). The setback viscosity of composite flours containing GGNBR was significantly lower than other flours. The presence of GBRF and GGNBRF significantly lowered specific volume and expansion ratio of breads. However, all sensory liking scores, except for appearance, were not significantly different among composite flour breads. Overall liking scores of all breads ranged from 6.8 to 7.2 (like moderately). This study demonstrated feasibility of incorporating GBRF and GGNBRF up to 50% by weight in bread formulations without compromising sensory liking.     

面粉企业生产管理浅识

结合生产实践,从人员、生产技术、安全文明生产三个方面阐述了制粉企业生产管理的主要措施,对面粉加工厂实现高产、高效有着积极的指导意义。     

碘化钾-吖啶红体系光度法测定小麦面粉中的过氧化苯甲酰

采用碘化钾-吖啶红分光光度法对小麦面粉中过氧化苯甲酰含量进行了测定。在硫酸介质中,有聚乙烯醇存在的情况下,过氧化苯甲酰氧化I-生成I3-,I3-与吖啶红发生离子缔合反应,导致KI-吖啶红-聚乙烯醇溶液体系的吸光度下降,在525 nm波长下,过氧化苯甲酰在0.04～6.0 mg/L内与吸光度的改变量呈线性关系,据此建立了测定小麦面粉中过氧化苯甲酰的碘化钾-吖啶红分光光度法,该法用于小麦面粉中过氧化苯甲酰的测定,平均回收率为98.2%与101.6%。