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1.
采用脱脂乳蛋白和大豆分离蛋白两种不同组成和结构的蛋白质构建冰淇淋乳液,通过分析蛋白质/蔗糖酯的红外光谱、脂肪球表面蛋白质吸附特性、zeta电位、粒径以及搅打凝冻后乳液的微观结构,研究蔗糖酯质量分数对两种蛋白乳液体系脂肪球低温失稳的影响;在最佳蔗糖酯质量分数条件下,采用大豆分离蛋白对乳蛋白进行不同比例的替代,探究不同蛋白...  相似文献   

2.
利用物理方法和生物技术方法相结合的方法获得米糠营养提取物,探讨了提取条件对米糠营养提取物提取率的影响.结果表明,以纤维素酶处理、蔗糖脂肪酸酯(SE=13)为乳化剂、采用温水结合超声波的二次提取处理的方法,利于提取米糠营养提取物.  相似文献   

3.
采用脂肪酶Lipozyme(TL IM)为催化剂,马铃薯淀粉与硬脂酸为反应底物、焦磷酸钠为辅助剂,合成硬脂酸淀粉酯。在脂肪酶添加量为淀粉质量10%的条件下,考察了底物比、辅助剂用量、反应时间、反应温度对酯化效果的影响,确定了酶法合成硬脂酸淀粉酯的最佳条件:淀粉6.0g、硬脂酸16g、焦磷酸钠1.0g、反应时间42h、反应温度65℃,制得取代度为0.036的淀粉酯。所得淀粉酯具有良好的乳化能力。  相似文献   

4.
本文以五元瓜环为催化剂,用三氯化磷与无水醇进行酯化反应合成亚磷酸二烷基酯。通过正交试验,得到最佳工艺条件:在以四氯化碳作为溶剂,醇/三氯化磷摩尔比为3,催化剂的用量为反应物总质量的1%,反应温度为50℃,反应时间为120min。在该条件下,合成了亚磷酸二乙酯、亚磷酸二甲酯、亚磷酸二正丙酯、亚磷酸二异丙酯和亚磷酸二正丁酯,收率较好。  相似文献   

5.
米糠营养提取物提取条件的研究   总被引:1,自引:0,他引:1  
利用物理方法和生物技术方法相结合的方法获得米糠营养提取物,探讨了提取条件对米糠营养提取物提取率的影响。结果表明,以纤维素酶处理、蔗糖脂肪酸酯(SE=13)为乳化剂、采用温水结合超声波的二次提取处理的方法,利于提取米糠营养提取物。  相似文献   

6.
稳定剂的选择及配比确定是复合果蔬汁运动饮料研制中的重要环节.通过Design Expert对复合果蔬汁运动饮料中的稳定剂进行最佳配方设计,建立各组分比例对产品感官质量之间的回归模型,考查各组分间的相互效应.获得复合果蔬汁运动饮料稳定剂的最优配方为:CMC-Na 0.33%、黄原胶0.16%、蔗糖酯0.14%、单甘酯0.06%.  相似文献   

7.
以紫薯和燕麦为原料研制复合饮料。通过单因素试验和正交试验优化工艺参数,结果表明:最佳配方为紫薯汁与燕麦浆质量比6∶4、柠檬酸用量0.015%、白砂糖用量5%;最优稳定剂蔗糖酯0.15%+明胶0.20%+CMC-Na 0.15%。此条件下复合饮料品质最佳。  相似文献   

8.
无色高果糖浓缩苹果汁生产工艺试验   总被引:3,自引:2,他引:1  
采用蔗糖酶酶解法和脱色脱酸树脂进行了无色脱酸高果糖浓缩苹果汁的生产工艺试验.通过正交试验确定了苹果汁中蔗糖酶酶解条件、脱色条件及脱酸条件.结果表明:苹果汁中蔗糖的较佳酶解条件为:苹果汁浓度为120 g/L,酶质量比为7mg/kg,pH值为4.5,温度为5512;XDA-5脱色树脂的较佳脱色条件为:苹果汁浓度为200 g/L、pH值为3.5、温度为50℃、流速为150 mL/h;D380树脂在温度25℃、苹果汁浓度300 g/L、流速180mL/h时吸附分离果酸效果最佳.  相似文献   

9.
为了探索适宜的玉米黄素双棕榈酸酯(ZDP)乳液制备工艺,通过高压均质方法,采用2种天然乳化剂:大豆卵磷脂(SL)和乳清分离蛋白(WPI)和4种合成乳化剂:十聚甘油单油酸酯(PGE18)、十聚甘油单月桂酸酯(PGE12)、蔗糖酯(SE15)和吐温80(T80),以及2种不同油相:大豆油(SO)和中链甘油三酯(MCT),分别制备了ZDP乳液,研究了不同乳化剂种类和质量分数以及油相种类对ZDP乳液性质和稳定性的影响。同时,在最佳乳化剂条件下,研究了ZDP添加量对乳液性质的影响。研究结果表明:天然乳化剂乳化制备所得ZDP乳液平均粒径大,且稳定性一般。小分子合成乳化剂制得的ZDP乳液平均粒径小,但稳定性差异大。其中,PGE18为乳化剂时制备的乳液各项指标较好,且在质量分数为0.8%时乳化效果最好。MCT为油相较SO为油相制备所得乳液稳定性好。因此,选择质量分数为0.8%的PGE18为乳化剂,MCT为油相,高压均质可以制得粒径小于200 nm的ZDP乳液,且在4℃下贮藏28 d仍可保留约90%的ZDP。ZDP添加量变化在4~32 nmol/g时对ZDP乳液的粒径和电位无显著影响。  相似文献   

10.
以硼酸、丙三醇为原料,通过微波酯化法制备了硼酸双甘酯。以硼酸双甘酯和丙烯酰氯为原料合成了硼酸甘油丙烯酯,以此作为含硼功能单体,成功制备了以羟丙基甲基纤维素为骨架的硼缓释型高吸水性树脂。根据吸水倍率筛选含硼功能单体最佳添加量,并对产物的吸液倍率、吸液速率、保水性能以及基团结构和表观形貌进行了表征。由红外光谱曲线可以看出,试验成功制备了具有双键结构的硼酸甘油丙烯酯,并通过接枝聚合反应合成了含硼高吸水性树脂;当含硼功能单体添加量为丙烯酸质量的1%时,羟丙基甲基纤维素含硼高吸水性树脂吸水倍率为344. 06 g/g、吸盐倍率为44. 71 g/g; 35℃条件下,该含硼高吸水性树脂可保水72 h;重复使用6次后,该高吸水性树脂重复吸水率仍可达到60%以上,重复吸盐率仍可达到40%以上;该高吸水性树脂具有良好的硼缓释性,在去离子水中可持续缓释10 d,缓释硼总质量达182. 77μg,在育苗基质中可持续释放25 d,当添加量为育苗基质质量的0. 5%时,混合基质淋溶硼量比普通基质多0. 80μg/g。此外,羟丙基甲基纤维素含硼高吸水性树脂还具有良好的热稳定性,其表观形貌特征有利于促进对液体的吸收。  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.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
A European irrigation map for spatially distributed agricultural modelling   总被引:1,自引:0,他引:1  
We present a pan-European irrigation map based on regional European statistics, a European land use map and a global irrigation map. The map provides spatial information on the distribution of irrigated areas per crop type which allows determining irrigated areas at the level of spatial modelling units. The map is a requirement for a European scale assessment of the impacts of irrigated agriculture on water resources based on spatially distributed modelling of crop growth and water balance. The irrigation map was compiled in a two step procedure. First, irrigated areas were distributed to potentially irrigated crops at a regional level (European statistical regions NUTS3), combining Farm Structure Survey (FSS) data on irrigated area, crop-specific irrigated area for crops whenever available, and total crop area. Second, crop-specific irrigated area was distributed within each statistical region based on the crop distribution given in our land use map. A global map of irrigated areas with a 5′ resolution was used to further constrain the distribution within each NUTS3 based on the density of irrigated areas. The constrained distribution of irrigated areas as taken from statistics to a high resolution dataset enables us to estimate irrigated areas for various spatial entities, including administrative, natural and artificial units, providing a reasonable input scenario for large-scale distributed modelling applications. The dataset bridges a gap between global datasets and detailed regional data on the distribution of irrigated areas and provides information for various assessments and modelling applications.  相似文献   

18.
在介绍粉质仪和拉伸仪结构和原理的基础上,探讨了粉质曲线中吸水率、形成时间、稳定时间、弱化度和评价值等指标与面粉品质的关系,以及如何根据拉伸曲线中面团最大拉伸阻力、延伸度和拉伸曲线面积等指标来评价面团品质,并结合生产实际,概述了粉质仪和拉伸仪在面粉生产中的作用。  相似文献   

19.
农村信息化服务的现状及建设措施   总被引:2,自引:0,他引:2  
分析当前我国农村信息化服务的现状,提出加强农村信息化服务的新举措。  相似文献   

20.
车辆ABS控制算法的研究及探讨   总被引:1,自引:0,他引:1  
对现代汽车的ABS控制算法作了一些简单的介绍,同时指出了它们的一些缺陷,相应地提出了几种对ABS的其它控制方法并加以探讨,其中着重论述了ABS门限值控制算法中参考车速的确定方法和基于附着系数的控制算法。  相似文献   

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