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1.
采用响应面法优化酶法提取芡实蛋白工艺。考察了料液比、酶解时间、酶添加量、酶解温度和酶解pH值5个单因素对芡实蛋白提取率的影响,在单因素试验基础上,采用响应面法优化酶法提取芡实蛋白工艺参数。结果表明,影响芡实蛋白提取率的主次因素顺序为酶解pH>酶添加量>酶解温度;在料液比1∶20(gmL),酶解时间2 h,pH值5.0,酶添加量0.35%,酶解温度49 ℃的优化条件下,芡实蛋白平均提取率达80.38%。   相似文献   

2.
果胶酶提取南瓜淀粉的工艺研究   总被引:1,自引:0,他引:1  
研究了南瓜淀粉的提取工艺。以淀粉提取率为指标,探讨果胶酶添加量、pH值、酶解时间和酶解温度对淀粉提取率的影响,并采用正交试验确定了南瓜淀粉提取的最佳工艺条件。试验结果表明:南瓜淀粉的最适宜制备工艺条件:果胶酶添加量为1200U/g、pH值为7.0、酶解温度为40℃和酶解时间为4h,在此条件下,淀粉的提取率为64.1%。  相似文献   

3.
采用中温α-淀粉酶水解玉米淀粉,制备低DE值玉米淀粉基质的脂肪模拟物。通过单因素试验,对底物浓度、酶添加量、反应温度及酶解时间等对玉米淀粉水解程度的影响进行研究。通过正交试验确定玉米淀粉脂肪模拟物制备工艺的最佳条件为:酶添加量5U/g,底物浓度8%,酶解时间15min,反应温度70℃,此条件下制备的产品的DE值为3.18。在此条件下制备的脂肪模拟物可以形成类似脂肪的弱凝胶,而且具有20%浓度的凝胶最佳的感官指标。本研究为玉米淀粉类脂肪模拟物在低脂食品中的应用提供了理论依据。  相似文献   

4.
采用搅拌球磨对木薯淀粉进行机械活化,以机械活化淀粉为原料,α-淀粉酶为酶解试剂制备脂肪模拟物。以酶解产物的葡萄糖值(Dextrose Equivalent,DE)为评价指标,分别考察了机械活化时间、酶用量、底物浓度、pH值、酶解时间和酶解温度等因素对DE值的影响,并通过正交试验对其工艺条件进行了优化。结果表明:经机械活化后的淀粉酶解反应活性明显增大,对酶用量、底物浓度、pH值、酶解时间和酶解温度的依赖性降低,在常温下可以进行反应。主要的原因是淀粉经机械活化后,其紧密的颗粒表面受到破坏,降低了结晶度,有利于酶解试剂的渗透与反应,从而提高了反应的效率。通过正交试验确定了制备脂肪模拟物的最佳工艺条件:试验酶添加量5U/g、pH值6.5、水解温度45℃、底物浓度20%和水解时间10min,在此条件下制备的脂肪模拟物的DE值为2.63。并用X-射线衍射分析对活化淀粉和脂肪模拟物的结构进行表征。  相似文献   

5.
在单因素试验的基础上,采用Box-Behnken响应面设计优化漆酶酶解工艺,得到最优的工艺参数:漆酶添加量为1.5%、酶解时间为40min和酶解温度为45℃。在响应面分析优化的最佳条件下进行3次平行试验,得到总酚含量为2.98mg/L,预测值与实际测量值非常接近,说明响应值的试验值与回归方程预测值吻合良好。  相似文献   

6.
采用响应面试验设计,对脂肪酶水解大豆油的生产工艺进行优化,以水解温度、pH值和酶添加量为试验因子,以水解率为响应值,建立数学模型。结果表明:最佳水解工艺条件为水解温度39℃、pH值10.00和酶添加量0.010mg/g。水解率的模型预测值为75.78%,实际得到的水解率为75.91%。所得回归模型拟合情况良好,达到设计要求。  相似文献   

7.
以马铃薯淀粉为原料,采用复合酶水解马铃薯淀粉得到低DE值麦芽糊精来制备脂肪模拟物产品。研究酶配比、复合酶添加量、底物浓度、水解时间、水解温度对产品DE值的影响。通过单因素试验与正交试验确定最佳制备工艺(100 mL反应体系):复合酶配比为中温α-淀粉酶︰普鲁兰酶=4︰6、复合酶添加量1 125 U、底物浓度20%、反应温度60℃、水解时间10 min,此条件下水解产物的DE值为2.92。  相似文献   

8.
以大米淀粉为原料,以十二烯基琥珀酸酐为酯化剂,采用湿法制备十二烯基琥珀酸淀粉酯(SSDS)。研究淀粉乳浓度、反应温度、时间、体系pH值及DDSA添加量对十二烯基琥珀酸淀粉酯取代度的影响,在此基础上进行正交试验优化制备工艺。结果表明:淀粉乳浓度35%、反应温度40℃、pH值9.0、反应时间6 h及DDSA用量7.5%的条件下,十二烯基琥珀酸淀粉酯取代度最高、达0.029 700。  相似文献   

9.
周治国  徐树来  刘利军 《农机化研究》2012,34(10):169-171,225
以提高玉米淀粉糖的质量为目的,研究了玉米淀粉在液化和糖化过程中耐高温α-淀粉酶添加量、强效复合糖化酶、时间、pH值与温度等对产品质量的影响.经参数优化和工艺改进,最终获得了DE值达到99%以上、DX值达到96%以上的高品质玉米淀粉糖浆.  相似文献   

10.
龙眼多糖超声波-酶解辅助提取工艺优化   总被引:6,自引:1,他引:5  
采用Box-Benhnken中心组合试验设计优化龙眼果肉多糖的超声波-酶解辅助提取工艺,建立了包括纤维素酶添加量、超声波功率、酶解温度、pH值和时间的五因素回归模型.经回归模型分析并结合验证试验,确定多糖的最佳提取工艺条件为:以龙眼干果肉(含水率8.47%)为原料,选取纤维素酶(酶活大于等于200 U/mg)添加量2 000 U/g、超声波功率250 W、酶解温度55℃、pH值 5.0、时间60 min,在该条件下多糖提取率达38.71%,比传统热水法、酶法、超声波法和微波法分别高9.85%、6.41%、4.35%和3.99%,且差异达到显著水平(P<0.05).  相似文献   

11.
Overland water and salt flows in a set of rice paddies   总被引:1,自引:0,他引:1  
Cultivation of paddy rice in semiarid areas of the world faces problems related to water scarcity. This paper aims at characterizing water use in a set of paddies located in the central Ebro basin of Spain using experimentation and computer simulation. A commercial field with six interconnected paddies, with a total area of 5.31 ha, was instrumented to measure discharge and water quality at the inflow and at the runoff outlet. The soil was classified as a Typic Calcixerept, and was characterized by a mild salinity (2.5 dS m−1) and an infiltration rate of 5.8 mm day−1. The evolution of flow depth at all paddies was recorded. Data from the 2002 rice-growing season was elaborated using a mass balance approach to estimate the infiltration rate and the evolution of discharge between paddies. Seasonal crop evapotranspiration, estimated with the surface renewal method, was 731 mm (5.1 mm day−1), very similar to that of other summer cereals grown in the area, like corn. The irrigation input was 1874 mm, deep percolation was 830 mm and surface runoff was 372 mm. Irrigation efficiency was estimated as 41%. The quality of surface runoff water was slightly degraded due to evapoconcentration and to the contact with the soil. During the period 2001–2003, the electrical conductivity of surface runoff water was 54% higher than that of irrigation water. However, the runoff water was suitable for irrigation. A mechanistic mass balance model of inter-paddy water flow permitted to conclude that improvements in irrigation efficiency cannot be easily obtained in the experimental conditions. Since deep percolation losses more than double surface runoff losses, a reduction in irrigation discharge would not have much room for efficiency improvement. Simulations also showed that rice irrigation performance was not negatively affected by the fluctuating inflow hydrograph. These hydrographs are typical of turnouts located at the tail end of tertiary irrigation ditches. In fact, these are the sites where rice has been historically cultivated in the study area, since local soils are often saline-sodic and can only grow paddy rice taking advantage of the low salinity of the irrigation water. The low infiltration rate characteristic of these saline-sodic soils (an experimental value of 3.2 mm day−1 was obtained) combined with a reduced irrigation discharge resulted in a simulated irrigation efficiency of 60%. Paddy rice irrigation efficiency can attain reasonable values in the local saline-sodic soils, where the infiltration rate is clearly smaller than the average daily rice evapotranspiration.  相似文献   

12.
车用发动机润滑油失效规律与更换周期研究   总被引:7,自引:0,他引:7  
研究在正常使用条件下10W/30-QC级润滑油用于某型车用发动机时所表现的失效规律,确认期服从两参数Weibull分布,并给出分布的尺度参数η和形状参数m之最佳线性无偏估计(BLUE)同时,还为定量分析,计算车用发动机润滑油的使用可靠性和合理确定其更换周期提供了一套可供借鉴的方法,并给出了具体的计算实例。  相似文献   

13.
论述了我国农村剩余劳动力就业的意义,并针对我国农村剩余劳动力的现状,提出多渠道促进农村剩余劳动力就业的途径和办法。  相似文献   

14.
对引进的谷子新品种金谷子耐旱TG118进行品种比较试验和多点试种。结果表明:该品种抗旱、耐瘠、适应性强,稳产、高产、抗病抗风抗倒伏强,品质优良,粮草兼用,种植简单,省工易管;一般产量在6000kg/hm2以上,比当地主栽品种增产20%以上。最高产量达9450kg/hm2,适于在辽西北地区推广应用。  相似文献   

15.
对《种子法》存在问题的探讨   总被引:1,自引:0,他引:1  
《种子法》是我国种植业第一部法律。自实施以来,为依法加强种子管理提供了有力的法律支撑,促进我国种子产业发生翻天覆地的变化。但随着依法管理工作的深入和种子产业的快速发展,《种子法》及配套规章的一些问题逐步显现出来。对《种子法》及配套规章存在的问题进行深入分析,对需要进一步补充的章节以及需要调整的内容进行深入探讨,以求更加完善和明确。  相似文献   

16.
瓦房店市是我国重要的水果生产基地,在国内水果生产领域占有重要地位。随着水果市场化的不断深入,如何满足和适应国内外市场需求成为瓦房店市水果生产的关键问题。从瓦房店市水果生产实际出发,阐述了实施水果生产标准化的必要性,提出了发展水果生产标准化的具体措施。  相似文献   

17.
乡(镇)农技推广体系是农业发展的关键。介绍朝阳市农业技术推广体系的现状,针对目前体制及运行机制、服务手段等方面存在的问题,提出适合朝阳市乡(镇)农技推广体系改革与发展的对策,以期对全省农技推广体系改革和发展起到一些借鉴作用。  相似文献   

18.
草莓果味酸甜爽口,营养价值高,为人们所喜爱的应市鲜果之一。由于草莓易受损伤和微生物侵染,因此其采收、贮藏过程极为重要。介绍草莓采收过程中的注意事项以及11种贮藏保鲜技术的实施步骤和操作方法,推介9种加工方式,为草莓产业化提供技术支持。  相似文献   

19.
赵异 《湖南农机》2007,(3):31-32
在新世纪,面对机遇和挑战,党的十六大把“社会更加和谐”作为全面建设更高水平的小康社会的一个重要目标。中国人素有社会和谐的理想;西方人自古也向往社会和谐;借鉴东西方两种和谐社会思想的经验、教训,构建社会主义和谐社会理论。  相似文献   

20.
About 30 years have passed since the Government of Egypt embarked on implementing a series of large scale drainage projects. At present, about 3.8 million acres have been provided with drainage systems on the basis of systematic pre-drainage investigations and designs. The target is to provide drains in approximately 6.4 million acres in the Nile Valley and Delta.The implementation of the subsurface drainage system is carried out by the public sector and private contractors under direct supervision of governmental regional departments. The implementation process depends on many factors related to the drainage material, machinery, manpower, site requirements, farmers and organizations involved. Problems and constraints are sometimes challenging, however, the annual rate of implementation has gradually increased to 170,000 acre/year.This paper discusses the different aspects involved in the implementation process of drainage systems. The development in materials, machinery and construction technologies will be reviewed. Institutional and management factors are going to be also considered.  相似文献   

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