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121.
Grain compositional components impacting barley (Hordeum vulgare L.) use in food, feed and fuel products, must be combined with improved agronomic traits to produce a commercially viable barley cultivar. Little current information is available on grain composition and variability among winter barley genotypes. This study was conducted to determine the variability among modern hulled and hulless winter barley genotypes in grain composition. Barley types varied significantly in grain and kernel weight, starch, beta-glucan, oil and ash content, but not in protein concentration. Hulless barley had significantly higher grain test weight and starch concentration than hulled and malting types, and significantly higher beta-glucan than malting barley. Hulless barley had significantly lower kernel weights, oil, and ash concentrations than hulled and malting types. Higher starch and lower fiber and ash in grain of hulless barley versus hulled feed or malting type barley are characteristics that increase hulless barley desirability. Selection for high starch concentration among all barley types is feasible and will facilitate development of barley cultivars better suited for use in feed, malt, and ethanol production.  相似文献   
122.
Rice flour is a starchy material with low-cost, because it can be produced from rice that is broken during processing. The aim of this study was to develop biodegradable films based on rice starch and rice flour, and to characterize their physicochemical, microscopic and mechanical properties. Films from rice starch and rice flour were prepared by casting, with glycerol or sorbitol as plasticizer. SEM analysis of starch and flour films revealed compact structures. Rice flour films prepared in the present work have similar mechanical properties to those of starch based films. However, their water vapor permeabilities are two times higher than those of starch based films. Films with sorbitol were less permeable to water and more rigid, while films with glycerol are more plasticized and have poorer water vapor barrier properties. Therefore, preparing edible films from rice flour is a new alternative for using this raw material, which is sometimes much cheaper than commercial starches.  相似文献   
123.
Partial waxy (reduced amylose) and fully waxy (amylose-free) tetraploid durum wheats (Triticum turgidum L. var. durum) were used to investigate the relationships between both intra- and inter-granular variation in amylose concentration and starch functionality. Starches isolated from each genotype (intra-granular amylose variants) were compared to those of commercially available hexaploid wild-type and waxy starches, and functionalities compared to blends (inter-granular variants) of durum waxy and wild-type starches of 0, 6, 12, 18, 24, & 30% amylose content. Starch particle size distributions were not significantly different amongst partial waxy and wild-type genotypes; waxy samples had significantly smaller mean starch granule size. Few significant differences for crystallite melting and related intrinsic heat as determined by differential scanning calorimetry (DSC) were observed. The detected differences in starch gel color or gel strength generally were observed for the waxy samples relative to wild-type. Numerous significant differences were observed via Rapid-Visco Analysis (RVA). Pasting peak viscosity and breakdown were inversely proportional to % amylose. Wx-B1 null final viscosity differed significantly from that of all other blends and genotypes, demonstrating that genotypic differences exist amongst the partial waxy types, independent of amylose concentration per se.  相似文献   
124.
[目的]为桃栽培生产提供理论依据。[方法]试验以3年生实生桃树为材料,NH4NO3为试验氮肥,设0、3、6g/盆三个施氮水平,探讨了不同施氮水平对实生桃树可溶性总糖和淀粉以及根内部组织构造的影响。[结果]根和叶片的可溶性糖含量随着施氮水平的提高呈增加趋势,以6g/盆最高,与对照及3g/盆区差异均达到0.05显著水平;淀粉含量却呈相反趋势,随着施氮水平的提高而呈下降趋势,以6g/盆含量最低,与对照达0.01显著水平。与对照、3g/盆处理相比,6g/盆根内部组织构造表现为维管中柱较大,维管束发达,皮层薄壁细胞间隙小,细胞圆润、饱满,细胞壁光滑,发育较好。[结论]适宜的施氮水平可促进桃树可溶性总糖的累积和根内部组织的发育。  相似文献   
125.
[目的]为了迅速准确的对中国各农业遗址中的淀粉粒残留物进行鉴定,需要进行现代植物淀粉粒形态变化研究和模拟实验分析不同试剂和实验处理方法对淀粉粒形态的影响。[方法]研究现代小麦成熟过程中淀粉粒形态变化,完成了对成熟小麦的一系列模拟试验,如:研磨、超声波处理、盐酸和双氧水处理、干燥处理。[结果]成熟过程中小麦淀粉粒经历了由小到大的变化,最后稳定在由大、小两组淀粉粒组成;研钵研磨会使小麦淀粉粒粒径增大;较长时间的超声波处理使得小麦淀粉粒粒径增大;浓度为10%的盐酸和浓度为6%双氧水对小麦淀粉粒的影响很小;低温干燥处理不会使小麦淀粉粒出现糊化。[结论]该研究结论可有效地指导考古遗址古代样品淀粉粒分析实验流程以及处理参数的选择,提高了淀粉粒分析的效率和结果的可靠性。同时也为中国的农业起源和作物传播的研究提供了基础实验资料。  相似文献   
126.
小红豆淀粉颗粒性质研究   总被引:1,自引:0,他引:1  
[目的]为小红豆淀粉资源的开发提供理论依据。[方法]研究了小红豆淀粉的颗粒性质,包括颗粒的形貌、X光-衍射图样、溶解度与膨胀度,链淀粉含量、葡聚糖结构等,并与大红豆及荷包豆淀粉进行了对比。[结果]小红豆淀粉颗粒多为卵圆形,少数不规则,溶解度与膨胀度随温度变化程度不大,总体趋势平缓上升,X光-衍射呈现A型晶体图样,结晶度为18.01%,相对链淀粉含量为36.5%。[结论]该研究对于开发食用豆类淀粉资源具有启发作用。  相似文献   
127.
A partial defoliation study was carried out on ‘Hayward’ kiwifruit vines with the aim of evaluating effects on fruit yield, changes in concentration of carbohydrates, and return bloom. At full bloom, ‘Hayward’ kiwifruit vines trained to the pergola system were submitted to 0% (control), 50% and 75% defoliation in the 2.0 m wide central horizontal area of the canopy. This area represents the vine ‘replacement cane zone’ (RCZ), whereas the remaining external area represents the ‘fruiting zone’ (FZ). Removing 50% of the leaves resulted in a small (−9 g in the RCZ and −3.3 g in the FZ), but significant, reduction in fruit weight compared to the control vines. More severe defoliation (75%) reduced fruit weight by 13 g in the RCZ and 7 g in the FZ. The defoliation treatment reduced the concentrations of starch and total soluble carbohydrates (glucose + fructose + sucrose) in the shoots and starch in trunk bark compared to those in control vines. The treatments caused a large reduction in return bloom, expressed as number of flowers per winter bud, by about 25% and 53% in vines with 50% and 75% defoliation, respectively.  相似文献   
128.
Recently, new varieties of hull-less barley have been developed with altered carbohydrate traits. To our knowledge, there is no study on metabolic characteristics in ruminants of the proteins in the newly developed hull-less barley varieties. The objectives of this study were to: compare metabolic characteristics of the proteins of zero-amylose waxy (CDC Fibar), low-amylose waxy (CDC Rattan), high-amylose (HB08302), and normal starch (CDC McGwire) hull-less barley. In situ animal trials were carried out to generate the original rumen fermentation data for modeling nutrient supply to dairy cattle by using two dairy nutrition models – Dutch DVE/OEB system and NRC 2001. The major comparisons were made in terms of i) truly absorbed protein in the small intestine (DVE or MP, and ii) degraded protein balance (DPB). The study revealed that zero-amylose waxy hull-less barley was superior (P < 0.05) in both DVE (123 vs. 117, 114, 103 g kg−1 DM) and MP (112 vs. 93, 96, and 87 g kg−1 DM) when hull-less barley was evaluated as a single feed for dairy cattle. All of four hull-less barley varieties had negative DPB (DPBOEB; −37.4, −17.1, −30.2, and −28.2 g kg−1 DM for normal starch, zero-amylose waxy, waxy, and high-amylose cultivar, respectively), indicating the potential N shortage. In conclusion, the alteration of starch structure in granule provided a relatively balanced energy and protein for microbial synthesis in the rumen. The DVE and DPB predicted by using the DVE/OEB system can be explained (r2 > 0.76) by the equivalent parameters, predicted by using the NRC 2001 model. The alteration of starch structure in granule affects metabolic characteristics of the proteins of hull-less barley in ruminants.  相似文献   
129.
分别以玉米淀粉、小麦淀粉、马铃薯淀粉为原料,采用二步法按不同配比制备多层瓦楞纸生产线用淀粉胶黏剂,并对其性能进行研究。结果表明,糊化温度随淀粉胶质量分数和NaOH质量分数的增大而降低;SteinHall黏度随NaOH质量分数增大先减小,当NaOH质量分数超过0.7%时,Stein-Hall黏度迅速增大。在同一温度时,Brabender黏度从大到小依次为马铃薯淀粉胶、小麦淀粉胶、玉米淀粉胶;经过同一放置时间时,Brabender黏度从大到小依次为马铃薯淀粉胶、玉米淀粉胶、小麦淀粉胶。  相似文献   
130.
Addition of wheat bran to sorghum flour (Dabar cultivar) at two extraction rates 72% and 80% resulted in lowering reducing sugars. The percent decreasewas 75.6% compared with the control at the end of fermentation period. There was a highly significant (p 0.05) increase in crude fiber content as a result of addition of wheat bran. The increase was from 0.8 to 5.2 and from 0.5 to 5.3% for the 80% S/WB and 72% S/WB blends, respectively. Sorghum bread containing wheat bran was lower in reducing sugars and showed a significant increase (p 0.05) in starch content. Sorghum bread containing wheat bran resulted in a lower in vitro protein and starch digestibilities.  相似文献   
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