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121.
小麦蛋白质和淀粉性状与面包品质关系研究进展 总被引:3,自引:0,他引:3
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。 相似文献
122.
亲水胶体抗馒头老化效果的研究 总被引:1,自引:0,他引:1
馒头的老化是制约馒头工业化进程的一个关键问题。采用单因素试验和正交试验,研究3种亲水胶体(黄原胶、海藻酸钠、卡拉胶)对馒头制品在温度4℃贮存下的抗老化效果。试验结果表明,黄原胶、海藻酸钠和卡拉胶对馒头均有一定的抗老化效果。通过正交试验,得到抗馒头老化效果较好的3种胶体复配比例为:黄原胶添加量为0.15%,海藻酸钠添加量为0.05%,卡拉胶添加量为0.15%。 相似文献
123.
Tilman J. Schober Scott R. Bean Daniel L. Boyle Seok-Ho Park 《Journal of Cereal Science》2008,48(3):755-767
Gluten-free bread was prepared from commercial zein (20 g), maize starch (80 g), water (75 g), saccharose, NaCl and dry yeast by mixing above zein's glass transition temperature (Tg) at 40°C. Addition of hydroxypropyl methylcellulose (HPMC, 2 g) significantly improved quality, and the resulting bread resembled wheat bread having a regular, fine crumb grain, a round top and good aeration (specific volume 3.2 ml/g). In model studies, HPMC stabilized gas bubbles well. Additionally, laser scanning confocal microscopy (LSCM) revealed finer zein strands in the dough when HPMC was present, while dynamic oscillatory tests showed that HPMC rendered gluten-like hydrated zein above its Tg softer (i.e. |G*| was significantly lower). LSCM revealed that cooling below Tg alone did not destroy the zein strands; however, upon mechanical impact below Tg, they shattered into small pieces. When such dough was heated above Tg and then remixed, zein strands did not reform, and this dough lacked resistance in uniaxial extension tests. When within the breadmaking process, dough was cooled below Tg and subsequently reheated, breads had large void spaces under the crust. Likely, expanding gas bubbles broke zein strands below Tg resulting in structural weakness. 相似文献
124.
在传统真空包装工艺的基础上,研究了无菌真空热包装生产工艺。通过进行产品感官评定、VC测定和菌落总数测定,对无菌真空热包装和传统真空包装两种工艺对比分析,结果表明无菌真空热包装工艺是可行的,并具有一定优势。 相似文献
125.
Evaluation on Chinese Bread Wheat Landraces for Low pH and Aluminum Tolerance Using Hydroponic Screening 总被引:1,自引:0,他引:1
DAI Shou-fen YAN Ze-hong LIU Deng-cai ZHANG Lian-quan WEI Yu-ming ZHENG You-liang 《中国农业科学(英文版)》2009,8(3):285-292
Aluminum (Al) toxicity often takes place in acidic soils with a pH of 5.5 or lower. Breeding and cultivation of Al tolerance wheat can partially protect wheat escaping from Al toxicity. The scarcity of the tolerant sources impedes the wheat breeding. In order to find new Al tolerance sources, we screened 173 bread wheat landraces from Tibet of China using hydroponic screening. It was indicated that: (1) There were diversities on the root regenerate length (RRL). The RRL of a large of landraces were longer than 7.00 cm in pH 7 (58.38%) and pH 4.5 (66.47%), but shorter than 5.00 cm in pH 4.5 +50μM Al^3+ (80.93%). The low pH showed either promotion or restraining effects depend on landraces, but Al toxicity under low pH only showed restraining effects on the root elongation. (2) There were also diversities on root tolerance index of low pH (RTI 1) or root aluminum tolerance index (RTI2) among cultivars. The RTI1 varied from a narrow range but with relatively high value (0.8722-1.2953) in comparison with that of RTI2 (0.3829-1.0058), and the RTI1 of approximately 60% landraces was higher than 1.0000, the RTI2 of only 19.07% landraces was higher than 0.7000, suggesting that Al toxicity acted as an important factor for the reduction of the root elongation under acidic soils. (3) The RTI 1 of many wheats was higher than 1.0000, and As2256 and As2295 were the most tolerant for low pH, with RTI1 1.2953 and 1.2925, respectively. (4) Based on RTI2, seven wheats showed similar or higher tolerance to Al toxicity than Chinese Spring (CS), a known tolerance wheat. Much better tolerance existed in landraces of As1543 and As1242, which can be used as the new parents for Al tolerant breeding. 相似文献
126.
脱脂和重组对面粉理化特性和烘焙品质的影响 总被引:3,自引:0,他引:3
选用3个筋力不同的小麦品种(系),通过比较其采用脱脂面粉、重组面粉和原面粉,研究了小麦脂类对面团揉混特性和面包加工品质的影响。结果表明,(1)3个品种(系)面粉脱脂前后蛋白质含量、沉淀值和灰分含量无显著性差异,但脱脂后面粉白度显著提高。(2)脱脂后3个品种(系)揉混仪峰高和峰宽增大,衰落角变小。(3)面粉脱脂后面包加工品质有所改善,其作用大小与蛋白质的质量和蛋白质间的互作有关。脱脂面粉加入起酥油对面包品质无明显改善作用,起酥油是通过面粉脂类对面包品质产生作用的。 相似文献
127.
128.
Suitability of wheat (Triticum aestivum L.) for many food products depends on its unique protein. Elevated grain protein content (GPC) and its quality influences
the bread making properties of wheat. The objective of this study was to examine the association of elevated GPC with agronomic
and end-use quality in two hard red spring wheat recombinant inbred (RI) populations derived from wild emmer (Triticum turgidum L. var. dicoccoides). The two hard red spring populations (ND683/Bergen and Glupro/Bergen) were developed using a single-seed-descent method.
ND683 and ‘Glupro’ are high in GPC (180 g kg-1), presumably due to the introgression of gene(s) from Triticum turgidum L. var. dicoccoides and ‘Bergen’ is low in GPC (145 g kg-1). From each of the two populations 12 high- and 12 low-GPC RI lines (F5:7) were selected for replicated testing at two North Dakota (ND) locations in 1995. In both populations, the high-GPC lines
had significantly (p < 0.05) higher values compared to the low-GPC lines for mean GPC and water absorption. Mean grain yield of the high-GPC lines
was not significantly different from the low-GPC lines in both populations. In the ND683/Bergen population, the high-GPC lines
had significantly (p < 0.05) higher values than the low-GPC lines for mean plant height, days to heading, and flour extraction. GPC was significantly
(p < 0.05)and negatively associated with test weight and also significantly (p < 0.01) and positively associated with water absorption in the Glupro/Bergen population. In these populations, results suggested
that it may be possible to select lines that combine higher GPC and acceptable yield level, but later in maturity and taller
in plant height.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
129.
南美斑潜蝇为害芹菜的产量损失和经济阈值研究 总被引:2,自引:0,他引:2
本项研究结果表明:(1)在塑料大棚内,南美斑潜蝇虫道面积百分率与芹菜产量呈负相关,而与芹菜产量损失率呈正相关,直线回归方程分别为Y=3.3658-0.02675X和Y=2.15899 0.08184X,即虫道面积百分率每增加1%,产量减少0.02675kg,产量损失率增加0.08184%。(2)南美斑潜蝇为害大棚芹菜经济阈值数学模型:X=14.0845ln 23.1575L/68.075-L。 相似文献
130.
对小麦品系Saratovskaya29的不同Rht等位的一套近等基因系进行了田间试验,以测定6个矮杆基因的育种值。在不灌溉、灌溉并施用不同剂量的肥料(N120,P100,K60和N180,P160,K100)三种条件下测定Rht基因对株高、产量及产量构成因子、品质的影响。结果表明,Rht基因可以用于伏尔加河地区条件下魏杆小麦品系的选育。 相似文献