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31.
The possibility of using naked barley for food products is gaining popularity due to its dietary fibre content, especially β-glucans. The technological process (dough preparation, fermentation and baking) influences bread quality but also may contribute to degradation or preservation of valuable grain components. The aim of the study was to investigate the effects of different wholemeal barley flour share and bread production method on the quality of bread and non-starch polysaccharides content and solubility.Barley enriched bread contained more both soluble and insoluble dietary fibre and β-glucans, products of 40% barley share contained 67% more total dietary fibre and 160% more β-glucans than control. However, barley incorporation decreased the amount of soluble arabinoxylans. High barley contents contributed to the breads’ volume reduction by 14% and change in their crumb and crust colour. However, barley enriched breads gained higher ratings of taste than wheat bread. Barley sourdough fermentation improved breads’ volume, colour and sensory properties. Sourdough fermentation also resulted in higher concentration of dietary fibre, arabinoxylans and β-glucans. The beneficial effect of barley addition to wheat bread may be successfully enhanced by using barley wholemeal sourdough fermentation.  相似文献   
32.
Four sets of durum samples were used in this study to further understand the interrelationships among hard vitreous kernels (HVK), protein content, and pigment concentration, with a focus on the interaction and synergistic effects of protein content and vitreousness on durum quality. HVK level increases with higher protein content in the range of 9.5–12.5%, but this relationship is less evident in durum samples with high protein content (12.5–14.5%). Both protein content and kernel vitreousness can significantly affect durum milling quality. White starchy kernels (WSK) in low protein durum have a very detrimental impact on milling and pasta processing quality, but high protein content can mitigate the adverse impact of WSK on durum quality. Although protein content plays a dominant role, higher HVK might contribute positively to pasta firmness. There was no significant difference in yellow pigment content between HVK and WSK. However, pigment loss from semolina to dough was higher for WSK than HVK. Despite the difference in protein content, HVK and WSK have little difference in gluten strength. The monomeric protein was preferentially accumulated in HVK. The glutenin proteins of HVK and WSK were similar in the ratios of 1Bx/1By and HMW/LMW-GS.  相似文献   
33.
In this study, the effect of steam explosion (SE) treatment on microstructure, enzymatic hydrolysis and baking quality of wheat bran was investigated. Coarse and fine bran were treated at different steam temperatures (120–160 °C) and residence times (5 or 10 min) and then hydrolysed with carbohydrase enzymes. The SE treatment increased water extractable arabinoxylan (WEAX) content from 0.75 to 2.06% and reducing sugars from 0.92 to 2.41% for fine bran. The effect was more pronounced with increased SE temperature and residence time. The highest carbohydrate solubilisation was observed in fine bran at SE treatment of 160 °C, 5 min. WEAX content increased to 3.13% when this bran was incubated without enzyme, while WEAX content increased to 9.14% with enzyme addition. Microscopic analysis indicated that cell wall structure of wheat bran was disrupted by severe SE conditions. Supplementation of SE treated (150 °C, 10 min) bran at 20% replacement level decreased the baking quality of bread. However SE followed by enzymatic hydrolysis increased specific volume and decreased crumb hardness (on the day of baking and after three days of storage). Phytic acid content of bread supplemented with SE treated bran was lower than the one supplemented with untreated bran.  相似文献   
34.
白茶寿眉预防小鼠肥胖作用研究及安全性评价   总被引:1,自引:0,他引:1  
取1、3、7年寿眉(白茶)制备白茶提取物(White tea extracts,WTEs)。在对雄性C57BL/6J小鼠喂饲高脂饲料的同时给予WTEs干预,诱导建立预肥胖模型。观察小鼠体质量增量、摄食量、脂肪和肝脏组织病理学变化,统计脂肪湿重,测定血脂及血转氨酶水平。q PCR测定小鼠肝脏中脂代谢相关基因表达。综合评价WTEs预防小鼠肥胖功效及其安全性,并对其机制进行探究。结果显示,WTEs在无肝毒性和生长抑制作用条件下,能抑制脂肪细胞分化和脂肪的过度积累,还能下调SREBP-1c、FAS和ACC1的转录水平,抑制肝脏脂肪酸合成和脂肪过度积累,有效预防肥胖和脂肪肝的发生。高剂量下,WTEs预防肥胖功效随白茶年份的增加而显著降低。  相似文献   
35.
雪单3 号是利用双单倍体育种技术选育的春白萝卜新品种。母本ED0108A 是以梅花春萝卜× 白玉春萝卜进行花药培
养获得的DH 系为轮回父本,与不育系进行多次回交,转育成的雄性不育系。父本ED3128 是由迟花春萝卜× 天鸿春萝卜进行
花药培养获得的DH 系。该品种生育期60 d(天),植株开展度45 cm,裂叶,小叶11 对,叶片数20,叶簇平展,叶色深绿;
肉质根长圆柱形,白皮白肉,根长36 cm,横径7.1 cm,单根质量1.1 kg,高抗黑腐病、芜菁花叶病毒病、黄瓜花叶病毒病和花
椰菜花叶病毒病,抗霜霉病,群体整齐度高。每667 m2 产量4 000~5 000 kg。适宜在湖北、湖南、河南、山东等地区早春栽培。  相似文献   
36.
目的:探讨大强度间歇游泳运动对青年肥胖女性减肥的效果。方法:20名自愿参加青年肥胖女性随机分为对照组和实验组各10名,实验组进行12周4次/周大强度间歇游泳运动,运动方案为以85%VO2max强度完成200m游、再以55%VO2max强度完成100m游、间歇休息3min为一组,重复6组;在运动计划实施前和12周结束时采用ZEUS9.9身体成分分析仪测定受试者身体成分。结果:与对照组或运动前比较,实验组青年肥胖女性的体重、BMI、腰围、臀围、WHR、体脂%、身体脂肪、内脏脂肪和皮下脂肪均出现极显著性或显著性减少(P<0.01,P<0.05),而肌肉量和蛋白质量则出现显著性增加 (p<0.05)。结论:大强度间歇游泳运动对青年肥胖女性有明显的减肥效果。  相似文献   
37.
The relationship between panicle structure and oat grain quality characteristics was examined in a winter oat (Avena sativa) experiment, cv. Gerald, fertilized with 80 and 200 kg/ha N. Spikelets on each whorl were counted and separated into primary, secondary, and tertiary grains, which were counted and weighed, and the kernels extracted manually and weighed. Tiller and whorl rank had relatively small effects on weight per grain and kernel content. Nitrogen application significantly increased weight per primary and secondary grain on the main stem and T1, the first tiller, while spikelet and grain numbers increased only on T1. However, weight per grain and kernel contents in all whorls on both the main stem and T1 were not significantly affected by nitrogen. Although kernel contents were significantly affected by nitrogen application on some occasions, increases and decreases were less than 2.5%. Across the whole plant, numbers of primary and secondary grains increased at the higher nitrogen application, but weight per primary grain and kernel contents were unaffected. However, weight per secondary grain significantly increased at the higher nitrogen application, thus improving uniformity of grain size which is of value to millers.  相似文献   
38.
First‐year crops of diploid perennial ryegrass (cvs. Meridian, Bronsyn and Grasslands Impact) were sown on 1 April and 14 May 2008. Applications of trinexapac ethyl (TE) plant growth regulator at 0, 200 and 400 g a.i. ha?1 were used to shorten stems to examine the impact of seed growth. Seed filling followed a consistent sigmoidal growth pattern with a lag phase of 127°C days, and linear duration of 390°C days. Time to 95% of final seed weight was 517°C days. Seed yield increases from TE were from higher numbers of first‐grade seeds m?2, achieved by a higher rate of seed filling during the linear phase of 0·115 mg per °C day per spike. For all cultivars, the maximum stem dry weight occurred at 310–400°C days post‐anthesis, which suggest the stem was a strong sink. As seeds developed, their demand for assimilate increased and they drew more from the stem. At harvest, stem weights from TE treatments were 25% heavier than at anthesis, while untreated ‘Bronsyn’ and ‘Grasslands Impact’ stems were similar to those at anthesis. Thus, stems treated with TE contributed assimilates to increase seed yield but were still a net sink with assimilates in the stem at harvest. Trinexapac ethyl rate induced an inverse relationship between seed yield and stem height. This showed that competition for assimilate between stems and growing seeds limited the seed yield. Management or genetic factors that reduce stem height are likely to increase seed yields of perennial ryegrass.  相似文献   
39.
To provide food and nutrition security for a growing world population, continued improvements in the yield and nutritional quality of agricultural crops will be required. Wheat is an important source of calories, protein and micronutrients and is thus a priority to breed for improvements in these traits. The GRAIN PROTEIN CONTENT-B1 (GPC-B1) gene is a positive regulator of nutrient translocation which increases protein, iron and zinc concentration in the wheat grain. In the ten years since it was cloned, the impacts of GPC-B1 allelic variation on quality and yield traits have been extensively analyzed in diverse genetic backgrounds in field studies spanning forty environments and seven countries. In this review, we compile data from twenty-five studies to summarize the impact of GPC-B1 allelic variation on fifty different traits. Taken together, the results demonstrate that the functional copy of the GPC-B1 gene is associated with consistent positive effects on grain protein, Fe and Zn content with only marginally negative impacts on yield. We conclude that the GPC-B1 gene has the potential to increase nutritional and end use quality in a wide range of modern cultivars and environments and discuss the possibilities for its application in wheat breeding.  相似文献   
40.
熟牛油、生奶皮、白砂糖是制作新疆塔吉克族特色面制品的主要原料。通过正交试验确定三者在卡提拉玛中的添加量,研制具有新疆独特风味的卡提拉玛。在基本配方(高筋小麦粉500 g,酵母3 g,食盐2 g,鸡蛋清30 g,牛奶185 mL,饮用水100 mL,清油4 mL)的基础上,确定三者最佳添加量(以高筋粉为基重)。结果表明:加入熟牛油6 mL、生奶皮15 g、白砂糖3 g,可制作出色泽金黄、口感醇香、质地酥脆、具有生奶皮特有香气的新疆卡提拉玛。  相似文献   
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