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101.
A new fertilization method with deep placement of slow‐release N fertilizers, such as coated urea and lime nitrogen (LN) (calcium cyanamide) at 20 cm depth was found to promote soy bean seed yield. In the present study, the effect of deep placement of LN was investigated on different parameters such as growth, N accumulation, N2 fixation activity and yield of soy bean by applying LN at different rates in the rotated paddy field of Niigata, Japan. In addition to the basal fertilizer, ammonium sulphate (16 kg N ha?1), deep placement of LN was conducted by applying various amounts such as 50 kg N ha?1 (A50), 100 kg N ha?1 (A100) and 200 kg N ha?1 (A200) at 20 cm depth in separate plots. A 15N‐labelled LN fertilizer was also employed for each of the above treatments to calculate N utilization from LN in separate plots. Soya bean plant growth and N2 fixation activity were periodically analysed. Both plant growth and N accumulation were found to increase with LN treatment compared with control plants. An increase in N2 fixation activity was found in the A100 plots. The total seed yield was the highest in the deep placement of LN with A100 (73 g per plant) compared with other treatments. The visual quality of harvested seeds also showed that A100 enhanced the quality of seeds compared with other treatments. Thus, it is suggested that N fertilization management with particular reference to optimum amount of fertilizers is important for maximum growth, N2 fixation and enhancement of seed yield of soy bean.  相似文献   
102.
The Environmental Defense Fund (EDF) presents the idea of Zero Deforestation Zones (ZDZs) as a solution to implement private sector deforestation-free supply chain commitments by leveraging synergies between Jurisdictional REDD+, private sector initiatives, and governmental laws and regulations. Companies would source commodities that meet their deforestation commitments from jurisdictions implementing REDD+ programs, government monitoring systems, and functioning private sector initiatives. A definition of “zero deforestation” would be created through a multistakeholder process considering a number of different elements. ZDZs would align incentives between actors, generating multiple benefits for companies, governments, and local communities—including reduced costs of monitoring deforestation, low-risk areas for long-term investment, increased legal compliance, and conflict resolution between companies and local communities. Environmental integrity would also be improved because a larger area of forest would be protected, reducing risks of leakage and nonpermanence.  相似文献   
103.
为了进一步改善大豆分离蛋白的分散性及功能性质,该研究以大豆分离蛋白为原料,通过对天然大豆分离蛋白进行高压高剪切处理并联合冷冻干燥技术,制备大豆分离蛋白微粒,考察压力(60~100 MPa)对大豆分离蛋白微粒尺寸、功能性质及结构特性的影响,探究其构效关系。结果表明:随着压力逐渐增加,大豆分离蛋白平均粒径大幅度减小,粒径分布曲线向左侧移动,与天然大豆分离蛋白相比,在100 MPa时大豆分离蛋白粒径减小了1 631%,粒径曲线分布较宽。在60~100MPa压力范围内随着压力的增加。与天然大豆分离蛋白相比,大豆分离蛋白微粒的分散性指数(Protein Dispersibility Index, PDI)和功能性质均显著提高(P0.05),其中在100 MPa时大豆蛋白质的溶解性提高了172.98%,乳化活性和乳化稳定性分别增加了约28.71%和77.82%,持油性增加了约123.76%,起泡性随时间的变化其泡沫高度也均有所提高。由扫描电镜图可以观察到,未经过高压均质的大豆分离蛋白粒子呈聚集状态,球状的表面向内凹陷,经过高压均质联合冷冻干燥处理后的大豆分离蛋白微粒呈现网络结构。在高压和高剪切力的作用下,大豆分离蛋白微粒的疏水基团大量暴露,表面疏水性随之增加,静电斥力增加,α-螺旋和β-转角向β-折叠和无规则卷曲结构的转化是蛋白质的溶解性等功能性质提高的主要原因。溶解性等功能性质的提高有利于大豆分离蛋白更好的应用于食品加工行业,进一步为蛋白的理化性质及结构优化提供新思路。  相似文献   
104.
提高大豆蛋白冻融后乳化性改性工艺优化   总被引:4,自引:1,他引:3  
为了制备出经冷冻-融化后仍能保持较高乳化性的大豆蛋白,试验以葡聚糖为糖基化供体,采用湿法糖基化技术改性大豆蛋白。根据单因素试验的结果,建立了Box-Behnken模型对加工工艺进行优化,所得的模型拟合度高,切实可行,可用于实际分析和预测。利用响应面分析法探讨了蛋白浓度、蛋白与糖质量比、反应时间3因素对改性产物冻融前后乳化活性和乳化稳定性的影响,优化的工艺条件为:大豆分离蛋白(soybean protein isolate,SPI)质量浓度40 mg/mL,SPI与葡聚糖的质量比为1∶3,反应时间4 h。在此条件下得到的改性产物冻融稳定性显著(P0.05)高于未改性蛋白,冻融前后的乳化活性(emulsifying activity index,EAI)分别是空白对照样的1.687和1.780倍,乳化稳定性(emulsion stability index,ESI)分别是空白对照样的1.367和1.274倍。傅里叶红外光谱证明葡聚糖通过共价键接到大豆蛋白分子中,研究结果为制备冷冻食品加工专用大豆蛋白的产业化生产提供参考。  相似文献   
105.
生姜蛋白酶水解大豆分离蛋白的研究   总被引:3,自引:0,他引:3  
以部分纯化的生姜蛋白酶为酶源,对该酶在水解大豆分离蛋白的最佳条件等方面进行了较为详细的探讨。研究结果表明,生姜蛋白酶水解大豆分离蛋白的最佳条件为:温度60℃、酶加量2.0%、pH值6.O、水解5h,此时其水解度可达7.5%。经酶解处理后的大豆分离蛋白饮料,其离心沉淀率降低,稳定性增大。  相似文献   
106.
The effect of long-term consumption, under practical conditions, of beef extended with soy protein on serum zinc levels of men, women and children was studied. Fifty-two families were randomly assigned to consume for 180 days 1 of 7 beef products: all beef, beef extended with either soy isolate, soy concentrate or soy flour (20% reconstituted soy product, 80% beef), or beef extended with each of the 3 soy products fortified with 60 mg Fe and 25 mg Zn/100g protein. The beef product was consumed by the subjects as their principal source of protein for 1 meal a day (children 1–8 yrs) or 1–2 meals a day (11 per week) for adult men and women. A control group consumed their usual self-selected diet. Diet records (4-day) of all foods and beverages consumed by the subjects were obtained pre-study and 63±7 and 126±7 days for calculation of nutrient intakes. No deleterious effects were found on the serum zinc levels when subjects consumed beef extended with soy protein for 180 days.Mention of a trademark or proprietary product does not constitute a guarantee or warranty of the product by the U.S. Department of Agriculture, and does not imply its approval to the exclusion of other products that may also be suitable.  相似文献   
107.
Soy protein concentrate (Promosoy R Plus) was mixed with water to form a thick paste and autoclaved at 121°C for 10 min, 30 min, 2 h, or 4 h. Unautoclaved SPC served as a control. Nitrogen solubility measurements and SDS-PAGE analysis indicated that autoclaving resulted in the formation of soy protein aggregates, with a MW of 1 million daltons, held together by non-covalent and disulfide bonds. The 10 min, 30 min, 2 h, and 4 h SPC samples contained 6, 20, 27 and 39% less cysteine, respectively, than the SPC control. No significant differences were found in the PERs, 2.6-2-7, of a casein control, unautoclaved SPC control and 10 min and 30 min autoclaved samples. PERs of the 2 h and 4 h autoclaved samples, 2.0 and 1.9 respectively, were significantly lower than the other four diets. No significant differences were found in the apparent digestibility of the 10 min, 30 min, and 2 h autoclaved samples; the 4 h autoclaved sample however was significantly less digestible. Decreased PERs of autoclaved SPC samples were likely due to (1) crysteine destruction, (2) decreased protein digestibility, and (3) decreased food intake.  相似文献   
108.
The effects of stearidonic acid (SDA; 18:4n‐3) derived from SDA‐enhanced, genetically modified soybeans (Monsanto Company, St Louis, MO, USA) on growth performance and fatty acid (FA) composition of large Atlantic salmon (Salmo salar; 2.1 kg initial weight) were evaluated. There was a stepwise decrease in feed intake and subsequent weight gain of immature Atlantic salmon with increased replacement of fish oil by SDA soy oil from 0%, 50% to 100% added oil. SDA increased and n‐3 highly unsaturated FA (n‐3 HUFA; eicosapentaenoic acid + docosahexaenoic acid) decreased in the diet and corresponding fillet with increased SDA oil inclusion. Salmon with the same weight gain fed SDA oil compared with rapeseed oil at 50% fish oil replacement had similar n‐3 HUFA fillet levels indicating little or no increased synthesis of n‐3 HUFA from SDA for deposition in the fillet. However, elongation of dietary SDA to 20:4n‐3 for deposition in the fillet of SDA oil fed fish was indicated. The increased SDA and 20:4n‐3 in the fillet of Atlantic salmon fed SDA oil compared with rapeseed oil at 50% fish oil replacement may be more effective as precursors for EPA in humans than 18:3n‐3 which was in the fillet at similar levels.  相似文献   
109.
将Plackett-Burman因素水平设计应用于碱性蛋白酶水解大豆分离蛋白,以研究大豆分离蛋白酶水解物的抗氧化活性.通过测定水解产物的亚铁还原能力来确定其抗氧化活性的强弱,以此确定最佳水解工艺条件 为:反应温度72℃,底物浓度9%,酶用量(E/S) 1%,pH 7.0,水解时间5h.采用最适水解工艺条件得到水解...  相似文献   
110.
本试验以大米为主料,大豆、面粉为辅料制作米酱。大米、蔗糖、种曲、食盐分别选取3个水平进行优化筛选,采用混合曲霉接种、常温固体发酵30 d。进行感官评价,并检测米酱氨基氮、总酸含量。优化试验结果,原料中大米、蔗糖、种曲、食盐含量分别为80%、2%、1%、24%,大豆和面粉作为其它辅料,感官评分最高,氨基氮含量5.90%,总酸含量0.67%。  相似文献   
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