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1.
Triticale is a high yielding cereal grain, however low milling yields have discouraged its utilisation as a wheat alternative in processed flour products. This research investigated the role of hardness, grain size and tempering moisture on milling yields in modern triticale genotypes which do not exhibit shrivelled grain morphology. Replicate samples of three triticale varieties grown in two environments with a bread wheat standard were milled at five moisture contents. Both milling yield and ash content increased with decreasing tempering moisture in all genotypes. Triticale milling yield was between 7.1% and 10.1% less than wheat when tempered between 11% and 15% moisture respectively. The very hard textured triticale exhibited extremely low milling yield, similar to durum wheat. The ratio of ash in flour compared to bran was greater in triticale and the ash content of triticale flour could not be reduced to the level of wheat by alteration of tempering moisture. Surface area of larger triticale grain may also influence ideal tempering moisture, however further investigation is required. Milling yields and flour protein content in triticale can be improved by tempering triticale to lower moisture content, provided high ash content is not considered unfavourable in the final product.  相似文献   

2.
Ozone treatment (10 g/kg) of common wheat grains with a new patented process, Oxygreen®, used before milling was found to significantly reduce (by 10–20%) the required energy at breaking stage whatever the grain hardness and without changes in the flour yield. Detailed study of each of the milling steps undertaken on a hard type cultivar showed that both the breaking and the reduction energy were decreased. Reduction of the coarse bran yield was also observed concomitantly with an increase in the yield of white shorts. Biochemical characterization of the milling fractions pointed out changes in technological flour properties as starch damage reduction, aleurone content enrichment and increase of insoluble glutenin polymers. Measurement of wheat grain tissue mechanical properties showed that ozone treatment leads to reduction of the aleurone layer extensibility and affects the local endosperm resistance to rupture. These data as well as the direct effect of ozone oxidation on biochemical compounds could explain the observed changes in milling energy, bran and shorts yield and flour composition.  相似文献   

3.
A study was conducted to investigate the effect of dough formulation and hydration level on the rheological properties of pasta dough during pasta extrusion. Semolina 100%, whole wheat 100%, and the following mixtures semolina-whole wheat (49:51), semolina-flaxseed flour (90:10), whole wheat-flaxseed flour (90:10), and semolina-whole wheat-flaxseed flour (39:51:10) were the formulations used for the experiments. Dough was hydrated at 30, 32, and 34% moisture content. Pasta was extruded with a capillary and a semi-commercial pasta extruder to determine the apparent viscosity of the dough during extrusion conditions and its relationship to the behavior of the dough during pasta processing. Results showed that non-traditional pasta dough behaved like a shear thinning fluid that can be described by the Power Law model. Increased hydration levels and/or presence of flaxseed flour on the dough formulation decreased the apparent viscosity of the dough, which correlated with extrusion pressure, mechanical energy, and specific mechanical energy that were required to extrude the dough in the pasta extruder. The strong correlations found between the apparent viscosity of the dough and the pasta extrusion parameters indicates the possibility of using a capillary rheometer to determine the appropriate hydration level of ingredient formulations before extruding with a pasta press.  相似文献   

4.
Gluten extracted from fresh pasta by-products (PG) was enzymatically hydrolyzed by two different commercial proteases (Alcalase 2.4 L and Pancreatin) to different degrees of hydrolysis (DH 2.0, 4.0 and 8.0%). Commercial gluten (CG) was used as reference. The evaluation of functional properties of hydrolyzates from pasta gluten (PGH) and commercial gluten (CGH) showed that Pancreatin hydrolyzates had the highest emulsifying capacities. Regarding the foaming activity, all hydrolyzates performed better than unhydrolyzed gluten. PGH and CGH were added to wheat flour (1%) and their effects on dough rheology were studied. Most hydrolyzates with DH 8% increased dough thermal stability and elasticity during mixing, accelerated the denaturation rate of the protein network, and delayed the gelatinization speed of starch as the temperature increased. Texture profiles and specific volumes of breads from low quality wheat flour with added Pancreatin hydrolyzates (DH 8%) were comparable to those of breads from high quality flour. This showed the potential suitability of PGH and CGH as bread improvers.  相似文献   

5.
New maximum limits (ML) for deoxynivalenol (DON) in wheat and its products were set in Brazil in 2017, and new changes are scheduled for 2019. The concentration of DON in wheat and milling fractions (bran, shorts, break flour, reduction flour) was evaluated in samples from commercial fields to discuss the effects of the new legislation. Cleaned wheat samples contaminated with DON had concentrations ranging from 308 to 2373 ng g−1 (n = 29), and one sample had a concentration of 3426 ng g−1. DON concentration obtained in bran and shorts were significantly higher than that of the flours. Compared to the initial concentration in cleaned wheat, DON relative concentrations were 73 and 35% higher in bran and shorts, respectively, and 67% lower in the straight run flour (break plus reduction flour). The bran and straight run flour contained DON concentrations that were 62.1 and 17.2% respectively higher than that of the ML set in Brazil in 2017; additionally, these values would reach 65.5 and 34.5%, respectively, according to the changes to be in effect in 2019. The present study demonstrates DON distribution in wheat milling fractions, thus, providing updated information for the management of DON contamination for the industry and policymakers.  相似文献   

6.
A long-term (1999–2007) field experiment was conducted to investigate the effects of three nitrogen (N) fertilization rates (0, 130, and 300 kg N/ha) on micronutrient density in wheat grain and its milling fractions. At maturity, grains were harvested and fractionated into flour, shorts, and bran for micronutrient and N analysis. N fertilization increased iron (Fe), zinc (Zn), and copper (Cu) density in wheat grain compared to the control. Increase of N application rate from 130 to 300 kg N/ha, however, did not further increase the three micronutrient densities in grain. Micronutrient concentrations were usually highest in the bran and lowest in the flour. High N application increased Zn and Cu densities in all three milling fractions and increased Fe concentration in shorts and bran but not in flour. N application did not affect the manganese (Mn) concentration in grain. N fertilization changed the proportions of Fe and Cu in flour and bran but did not affect the distribution of Zn. Because N fertilization increased micronutrient accumulation in wheat grain, proper management of N fertilization has the potential to enhance the nutritional quality of this important food.  相似文献   

7.
Structure and health effects of inulin-type fructans have been extensively studied, while less is known about the properties of the graminan-type fructans in wheat. Arabinoxylan (AX) is another important indigestible component in cereal grains, which may have beneficial health effects. In this study, the fructan content in milling fractions of two wheat cultivars was determined and related to ash, dietary fibre and AX contents. The molecular weight distribution of the fructans was analysed with HPAEC-PAD and MALDI-TOF MS using 1H NMR and enzymatic hydrolysis for identification of fructans. The fructan content (g/100 g) ranged from 1.5 ± 0.2 in flour to 3.6 ± 0.5 in shorts and 3.7 ± 0.3 in bran. A correlation was found between fructan content and dietary fibre content (r = 0.93, P < 0.001), but with a smaller variation in fructan content between inner and outer parts of the grain. About 50% of the dietary fibre consisted of AX in all fractions. The fructans were found to have a DP of up to 19 with a similar molecular weight distribution in the different fractions.  相似文献   

8.
为探究氮肥在不同土壤肥力条件下对小麦的增产提质效应,以强筋小麦品种丰德存麦5号和中筋小麦品种百农207为供试材料,分别在三个地点设置0、180、240和300 kg·hm-2四个施氮水平,研究了不同施氮量对冬小麦籽粒产量和品质的影响。结果表明,地点、品种和施氮量均对小麦产量有显著影响,其中地点的影响最大,其次是施氮量,品种最小。在高肥力麦田,施氮量为180 kg·hm-2时产量最高,中高肥力麦田和低肥力麦田均以施氮量为240 kg·hm-2时产量最高。不施氮肥条件下,品质指标以高肥力麦田较高,低肥力麦田最低,表明基础肥力高有利于改善小麦品质。施用氮肥均显著提高了小麦籽粒中的蛋白质含量、蛋白质产量、沉淀值和湿面筋含量,延长了形成时间和稳定时间,各试验点表现一致。利用主成分分析将小麦品质性状转化为蛋白质因子和面粉粉质因子,结果表明,在低肥力麦田,施氮量对蛋白质因子的增强效应较大,在中高肥力麦田,施氮量能均衡提高蛋白质因子和粉质因子;在高肥力麦田,施氮量对小麦粉质因子的增强效应较大。不论土壤肥力高低,均以施氮量为240 kg·...  相似文献   

9.
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.  相似文献   

10.
Effects of bran concentration, bran particle size distribution, and enzyme addition – fungal phytase, fungal alpha-amylase – on the mixing and fermentative behaviour of wheat dough and on the amount of phytic acid remaining in bread have been investigated using a factorial design of samples 24. Bran concentration and bran particle size significantly affected all Farinograph parameters, whereas enzyme effects were particularly observed on both the water absorption of the flour and the parameters characterizing the overmixing. Water absorption was maximized in doughs with higher fine bran addition and/or in doughs with no enzymes, and was minimized in blends containing coarse added bran and alpha-amylase and/or alpha-amylase and phytase. alpha-Amylase addition had a significant positive effect on dough development and gassing power parameters during proofing. At low bran addition, phytate hydrolysis takes place to a greater extent than at high bran addition levels. Combination of bran with amylolytic and phytate-degrading enzymes could be advisable for overcoming the detrimental effect of bran on the mineral availability (phytase) or on the technological performance of doughs (alpha-amylase).  相似文献   

11.
为探讨稻茬小麦的氮硫肥施用技术,在水稻秸秆全量还田条件下设置0、195和270 kg·hm-2 3个施氮水平和0、30和60 kg·hm-23个施硫水平,研究氮、硫肥配施对小麦氮素吸收利用、籽粒产量和品质的影响。结果表明,随施氮量的增加,小麦穗数、穗粒数和产量均显著增加,面团形成时间和稳定时间延长,但施氮量达270 kg·hm-2时氮肥农学效率和表观利用率显著下降,籽粒支链淀粉、清蛋白、醇溶蛋白和谷蛋白含量降低。增施硫肥可使籽粒产量显著增加,延长面团形成时间和稳定时间,并提高籽粒支链淀粉、谷蛋白和总蛋白含量。相比其他氮、硫肥组合处理,施氮195 kg·hm-2配合施硫60 kg·hm-2提高了总氮素积累量、氮肥农学效率和氮肥利用效率;该组合处理下籽粒产量比仅施氮270 kg·hm-2处理提高了5.7%。此外,195 kg·hm-2施氮量配施硫60 kg·hm-2还提高了面团形成时间、稳定时间和蛋白各组分含量。这说明氮硫合理配施可提升小麦对氮素的吸收利用,起到提高籽粒产量、改善籽粒蛋白品质和粉质质量的作用;减氮条件下通过适量配施硫肥可作为小麦优质高效生产的栽培途径。  相似文献   

12.
Effects of bran concentration, bran particle size distribution, and enzyme addition – fungal phytase, fungal alpha-amylase – on the mixing and fermentative behaviour of wheat dough and on the amount of phytic acid remaining in bread have been investigated using a factorial design of samples 24. Bran concentration and bran particle size significantly affected all Farinograph parameters, whereas enzyme effects were particularly observed on both the water absorption of the flour and the parameters characterizing the overmixing. Water absorption was maximized in doughs with higher fine bran addition and/or in doughs with no enzymes, and was minimized in blends containing coarse added bran and alpha-amylase and/or alpha-amylase and phytase. alpha-Amylase addition had a significant positive effect on dough development and gassing power parameters during proofing. At low bran addition, phytate hydrolysis takes place to a greater extent than at high bran addition levels. Combination of bran with amylolytic and phytate-degrading enzymes could be advisable for overcoming the detrimental effect of bran on the mineral availability (phytase) or on the technological performance of doughs (alpha-amylase).  相似文献   

13.
为明确小麦面粉及鲜面片色泽的影响因素,选取10个江苏沿淮及淮南地区大面积推广小麦品种进行2年3点种植,比较不同品种、不同地点和不同年份面粉及鲜面片色泽差异并分析其影响因素,探讨面粉及鲜面片色泽与品质性状间的相关性。结果表明,扬麦11、扬辐麦4号和宁麦14的面粉及鲜面片色泽较好,亮度高、黄度低。基因型是决定面粉白度、亮度(L~*值)和黄度(b~*值)的主要因素;环境因素亦影响面粉及鲜面片色泽。扬麦16、宁麦14和郑麦9023在不同年度及不同地点的色泽表现稳定。面粉与鲜面片放置24h内的色泽间呈显著正相关;面粉白度与籽粒硬度和出粉率呈极显著负相关;面粉及鲜面片L~*值与蛋白质含量、湿面筋含量、揉混仪参数和粉质仪参数呈显著或极显著负相关,与糊化特性参数呈显著或极显著正相关。综上所述,面粉色泽主要由基因型决定,鲜面片色泽与面粉色泽显著相关,二者与籽粒品质具有显著相关性。在小麦育种中,可通过面粉色泽指标筛选高白度及品质的品种。  相似文献   

14.
The use of amaranth, quinoa and buckwheat for the production of gluten-free pasta was investigated in the present study. The aim of the work was to produce pasta of good textural quality, in particular, low cooking loss, optimal cooking weight and texture firmness. The results demonstrated that pasta produced from amaranth had decreased texture firmness and cooking time, while pasta from quinoa mainly showed increased cooking loss. In buckwheat pasta the least negative effects were observed. By combination of all three raw materials to one flour blend in the ratio of 60% buckwheat, 20% amaranth and 20% quinoa, dough matrix was improved. After decreasing dough moisture to 30%, addition of an increased amount of egg white powder of 6% and addition of 1.2% emulsifier (distilled monoglycerides) texture firmness as well as cooking quality of gluten-free pasta produced from such a flour blend reached acceptable values comparable to wheat pasta.  相似文献   

15.
The milling potential of hulled barley, hulled oat, triticale, rye and wheat was studied using a long tempering process and a laboratory four-roller mill. Regardless of the investigated cereal, the results indicated a significant influence (p < 0.05) of volume per surface area ratio on the milling yield and ash contents of the flour. The lowest milling yield was obtained in case of hulled oat. Solvent retention capacity profiles were determined for all investigated whole cereals and flours for predicting the contribution of different polymers to the functionality of samples. For all solvents higher values were obtained for the whole cereals compared to the corresponding flour. Thermo-mechanical properties of the whole cereals and refined flours were also investigated. If in case of wheat the gluten proteins play an essential role on dough behaviour during kneading at 30 °C, in case of triticale, rye, hulled barley and hulled oat, the fibers play a major role as well. Thermo-mechanical properties of starch registered a large variation between cereals and/or flours. The lowest torque value corresponding to starch gelatinization (C3) was registered in case of the hulled oat flour, 1.92 Nm, while the highest value in case of rye flour, 2.65 Nm.  相似文献   

16.
The target of this work was to develop a novel, industrially applicable process for simultaneously releasing different valuable components from wheat bran, including carbohydrates, oligomeric arabinoxylan and antioxidants. The process was based on alkaline pretreatment with potassium hydroxide (KOH) and subsequent enzymatic hydrolysis. Increasing KOH-dosage and thermal severity in pretreatment promoted carbohydrate solubilisation in hydrolysis, reaching glucose and arabinoxylan yields up to 86% and 76%, respectively. Release of antioxidants was particularly promoted by increasing KOH-dosage, while both the pretreatment severity and KOH-dosage promoted the release of oligomeric arabinoxylan in enzymatic hydrolysis. Two bran syrups, with or without KOH-treatment, were tested in bread making by substituting added sugar in the dough with bran syrup. The KOH-derived KCl also substituted 30% of NaCl in the bread formulation. The addition of bran syrup did not affect the baking properties of wheat bread dough. However, a decrease in bread flavour balance was observed with addition of syrup from KOH-pretreated bran. Conceptual level techno-economic assessment indicated that production of bran syrup would be economically feasible at a minimum selling price of 770 €/t and 1030 €/t with KOH-pretreatment and without KOH, respectively.  相似文献   

17.
The antioxidant potential of milling fractions from breadwheat and durum   总被引:1,自引:0,他引:1  
The effect of primary processing, namely milling, on the phenolic content and antioxidant capacity of two wheat cultivars, namely Canada Western Amber Durum (Triticum turgidum L. var. durum) and Canada Western Red Spring (Triticum aestivum L.) was studied. The milling products: bran, flour, shorts and feed flour fractions were examined. In addition, semolina was an end-product of durum wheat milling. Antioxidant activity of wheat phenoliocs was evaluated using oxygen radical absorbance capacity, inhibition of photochemiluminescence, the Rancimat method, and inhibition of oxidation of low-density lipoprotein cholesterol and deoxyribonucleic acid. The phenolic composition of wheat extracts was determined using high performance liquid chromatography. Bran showed the highest antioxidant activity whereas the endosperm possessed the lowest in both cultivars examined. The phenolic compounds are concentrated in the outermost layers namely the bran. The consumption of wheat with bran in the form of whole grain may provide beneficial health effects.  相似文献   

18.
Winter triticale, an abundant biomass source for producing biogas in Central Europe, has been bred until now for increased grain yield but not for early biomass yield. Therefore, our objectives were to assess the feasibility of breeding triticale for simultaneous improvement of early biomass and grain yield as well as to predict the early biomass yield using an index of traits measured at maturity stage. A representative sample of 100 triticale lines was evaluated in Experiment I at four locations in Germany. Traits were measured at two growth stages (early dough and full maturity). Genetic variances were significantly different from zero for all traits. The correlated response for early biomass yield estimated from grain yield (0.53) was high, which points to the efficiency of indirect selection. A multiple regression model was developed to predict early biomass yield. The reliability of the model was confirmed in an independent Experiment II with 49 lines. The calibration model explained 55% of total variation for early biomass yield. This clearly underlines that at least during earlier stages of selection, field testing can be carried out for grain yield and related traits to select potential genotypes with high biomass yield based on the developed regression model.  相似文献   

19.
为探究C、N供给时期和供给水平对小麦籽粒建成及蛋白质含量的影响,以冬小麦品种济麦22为材料,采用离体穗培养的方法,设置了三个蔗糖浓度(C1:20 g·L-1;C2:40 g·L-1;C3:80 g·L-1)和四个硝酸铵水平(N1:0.57g·L-1;N2:1.14g·L-1;N3:2.28 g·L-1;N4:4.56g...  相似文献   

20.
In this study, new films based on triticale flour were prepared by using the casting technique. Colour, microstructure, mechanical, physicochemical and water vapour barrier properties were determined. Triticale flour films were aged up to 60 days at 52% relative humidity and 25 °C. The influence of storage time on functional properties was also studied. All films presented high (from 84.01 to 85.21) lightness values (L*). Results showed that during storage the values of permeability of the films did not change significantly. Tensile strength, elastic modulus of Young and puncture force values increased and the percent of elongation at break decreased towards the last days of storage. Analysis of SEM images of films showed the appearance of small cracks at 60 days of storage. After 45 days of storage, triticale flour films maintained acceptable functional properties. In conclusion, films based on triticale flour showed properties that make them a substantial potential to be incorporated in food packaging applications.  相似文献   

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