微波有机相法制备辛烯基琥珀酸淀粉的研究

研究了在微波奈件下以辛烯基琥珀酸酐为酯化剂，在乙醇介质中对玉米淀粉进行改性制备辛烯基琥珀酸淀粉酯的工艺条件。着重讨论了乙醇、OSA、NaOH用量、淀粉含水量以及辐射时间对产物取代度的影响规律，并得到了最佳工艺条件。     

非晶颗粒态玉米淀粉制备辛烯基琥珀酸淀粉酯

以乙醇法制备的非晶颗粒态玉米淀粉、辛烯基琥珀酸酐为原料,研究辛烯基琥珀酸淀粉酯(SSOS)的合成工艺条件。探讨了反应时间、反应温度、碱用量、辛烯基琥珀酸酐、淀粉乳的浓度、水分含量对取代度(DS)和反应效率(RE)的影响。结果表明:在淀粉乳浓度为0.25g/mL,乙醇溶剂含水35%时,pH为8.5,反应温度为35℃时反应2h为最佳反应条件,得到取代度为0.0166。     

辛烯基琥珀酸淀粉酯的制备及其酶法降解的研究

以蜡质玉米淀粉为原料,辛烯基琥珀酸酐为亲核试剂,用正交试验方法确定了在不同条件下,制备辛烯基琥珀酸淀粉酯的最佳工艺参数,着重研究了酯化反应条件对反应取代度的影响。实验结果表明:在辛烯基琥珀酸酐添加量(淀粉干基重的3%)不变的条件下,淀粉乳的浓度、反应温度、反应体系pH值、反应时间对反应取代度均有较大影响。对制备的淀粉酯中的辛烯基琥珀酸酐残留量进行了测定,结果表明,利用本文确定的最佳反应条件制得的淀粉酯辛烯基琥珀酸残留量低于规定标准。利用α-淀粉酶对制得的淀粉酯进行了降解处理,探讨了利用不同的酶解时间,获得不同DE值样品的酶解条件。利用最佳工艺条件,进行了辛烯基琥珀酸淀粉酯的中试放大并获得了预期产品。     

银杏辛烯基琥珀酸淀粉酯的制备及消化性能评价

以银杏淀粉为原料,对水相法制备辛烯基琥珀酸淀粉酯的工艺进行了研究。在辛烯基琥珀酸酐添加质量分数为3.0%不变的情况下,通过单因素试验考察淀粉乳浓度、反应时间、反应温度、p H等因素对产品取代度和反应效率的影响。在此基础上,通过正交试验优化了制备银杏辛烯基琥珀酸淀粉酯的最佳工艺参数:银杏淀粉质量分数40.0%,反应温度45.0℃,p H 8.0,反应时间4.0 h。在此工艺条件下,银杏辛烯基琥珀酸淀粉酯取代度可以达到0.019 36,反应效率74.42%。淀粉消化性能试验表明银杏辛烯基琥珀酸淀粉酯对胰淀粉酶水解作用具有良好的抵抗能力,慢消化及抗消化特性显著。     

乙酰化辛烯基琥珀酸蜡质玉米淀粉酯的制备及性质研究

以蜡质玉米淀粉为原料,选取乙酸酐和辛烯基琥珀酸酐对其进行双重酯化改性,以取代度为衡量标准,确定了蜡质玉米双重酯化淀粉的制备顺序是先进行乙酸酐的乙酰化再进行辛烯基琥珀酸酐的酯化,得到产物乙酰化辛烯基琥珀酸蜡质玉米淀粉酯。按照确定好的酯化顺序,以实验室自制取代度为0.0768的乙酰化淀粉为原料,采用单因素和正交实验的方法研究湿法工艺制备乙酰化辛烯基琥珀酸蜡质玉米淀粉酯,得出最佳工艺条件为:在辛烯基琥珀酸酐加入量为3%的情况下,淀粉乳初始浓度30%,反应体系pH8.5,反应温度35℃,反应时间4h。采用最佳工艺条件所得产品辛烯基琥珀酸酐酯化取代度为0.0197,利用红外光谱分析方法对乙酰化辛烯基琥珀酸蜡质玉米淀粉酯的结构进行了初步表征,并对产品的乳化性及乳化稳定性、透明度、表观黏度等性质做了测定和分析。     

微波有机相法制备辛烯基琥珀酸淀粉酯乳化性能的研究

研究了在微波条件下，以乙醇为介质制备辛烯基琥珀酸淀粉酯，讨论了改性前后淀粉糊溶液对介质pH值、糖、盐等介质浓度的耐受性。同时对产品的乳化等糊液性能及其影响因素进行了详细的探讨，研究表明，利用微波有机相法制备的辛烯基琥珀酸淀粉酯，可作为性能优良的新型乳化增稠剂。     

辛烯基琥珀酸木薯淀粉酯在乳化桔子香精中的应用

以辛烯基琥珀酸木薯淀粉酯作为乳化桔子香精的乳化稳定剂,研究了相应的优化工艺条件.结果表明,辛烯基琥珀酸木薯淀粉酯可用于桔子乳化香精中,添加辛烯基琥珀酸木薯淀粉酯能制得较为稳定的乳化体系.优化工艺条件为:辛烯基琥珀酸木薯淀粉酯质量分数14%、取代度0 017、桔子香精质量分数6.5%、均浆温度为20℃、均浆时间为5min.在此条件下制得的乳化香精,稀释后仍有一定的稳定性.     

半干法制备辛烯基琥珀酸淀粉酯及其相关性质分析

以食品级玉米淀粉为原料、碳酸钠为催化剂、辛烯基琥珀酸酐为酯化剂,采用半干法工艺制备辛烯基琥珀酸淀粉酯,研究反应条件对产品取代度的影响.结果表明:当Na2CO3用量2％,辛烯基琥珀酸酸酐乙醇稀释比1∶2.5,反应温度130℃,反应时间120 min时制备的产品取代度为4.5460×10-3.与玉米原淀粉相比,随改性淀粉取...     

糯玉米辛烯基琥珀酸淀粉酯的制备及其RVA谱特性分析

以糯玉米淀粉为原料，对辛烯基琥珀酸淀粉酯的湿法制备工艺进行了研究，采用粘度速测仪（RVA）分析了不同取代度辛烯基琥珀酸淀粉酯的粘滞特性，并探讨了氯化钠和蔗糖对其粘滞特性的影响。结果表明，糯玉米辛烯基琥珀酸淀粉酯的制备工艺为：酸酐用无水乙醇稀释3倍；反应时间3h；反应温度35℃；pH值8．5；淀粉乳液浓度30％-35％；酸酐加入量为3％～5％。RVA谱分析表明，随着变性程度的提高，辛烯基琥珀酸淀粉酯的粘度增加，糊化温度降低；氯化钠抑制辛烯基琥珀酸淀粉酯的糊化，使其粘度显著降低，蔗糖则使其粘度稍有增加。该研究为糯玉米辛烯基琥珀酸淀粉酯在食品工业中的应用提供了理论依据。     

微波有机相法制备辛烯基琥珀酸淀粉的表征和流变学研究

研究了在微波条件下,以乙醇为介质制备辛烯基琥珀酸淀粉酯。通过红外、电镜、X衍射等测定,对产品的结构进行了表征,并讨论了淀粉糊的流变学性能。研究表明,利用微波有机相法制备的辛烯基琥珀酸淀粉酯,可作为性能优良的新型增稠剂。     

Oxidized banana starch–polyvinyl alcohol film: Partial characterization

Composites of polyvinyl alcohol, native banana starch, oxidized banana starch using glycerol like plasticizer, were studied by mechanical tests (MT), scanning electronic microscopy (SEM), differential scanning calorimetry (DSC) and solubility in water. The oxidized banana starch showed higher level of carboxyl groups than of carbonyl groups. Composites of native banana starch/polyvinyl alcohol and oxidized banana starch/polyvinyl alcohol showed irregularities, indicating incomplete dispersion of the polymers. However, the film elaborated with the blend oxidized banana starch/polyvinyl alcohol showed the highest mechanical properties and the melting temperature of the first transition, as well as the lowest water vapor permeability, indicating higher interaction between both polymers. The composite oxidized banana starch/polyvinyl alcohol showed higher water solubility than the one of its counterpart with native banana starch at 25°C, and similar values were obtained for both films at 60°C. The oxidation of banana starch in order to elaborate a film blended with polyvinyl alcohol improved some mechanical and barrier properties, and this composite could be used for specific applications in the packing of food.     

基于响应面法氧化辛烯基琥珀酸糯玉米淀粉酯制备的优化研究

以糯玉米淀粉为原料,先对其氧化处理,然后用辛烯基琥珀酸酐对氧化淀粉进行酯化.在单因素基础上选取影响酯化取代度明显的四个因素(pH值、反应温度、淀粉乳浓度、反应时间)在酸酐加入量为3%及酸酐用乙醇稀释5倍的前提下进行响应面设计,得出了最优条件:pH值为8.4,反应温度为36%,淀粉乳质量分数为40%,反应时间为3.5 h,酯化剂用量3%(占淀粉干基比),此时制备产品的取代度可达0.0196.     

Associations between grain characteristics and alcohol yield among soft wheat varieties

Samples of ten winter wheat varieties, grown at four locations on the eastern side of the UK were assessed for alcohol yield. There was a strong negative association between alcohol yield and grain nitrogen content, but this was strongly influenced by differences between the sites, with a range of alcohol yields observed at given nitrogen levels. Inclusion of grain size parameters, thousand grain weight and grain length:width ratio, along with nitrogen, in a multiple regression, enabled more accurate prediction of alcohol yield for most of the varieties, indicating that grain size would be a useful parameter for selecting the best samples within varieties. A small‐scale measurement of hot water extract, along with grain nitrogen content, gave a reasonable prediction of alcohol yield, but the regression equation was not consistent across seasons. Starch content and turbidity (a measure of the ease of starch release) were both shown to be significantly influenced by variety, but not to give significant correlations with alcohol yield over a range of samples. Positive expression of these characters appeared, however, to contribute to improved alcohol yield in certain of the varieties. It was concluded that different genetic mechanisms influence alcohol yield and that improved breeding lines could be developed by combining positive alcohol yield attributes from complementary parents. Copyright © 2007 Society of Chemical Industry     

变性淀粉/聚乙烯醇复合膜的研究进展

随着环保意识的日益增强,人们对绿色可降解包装材料的需求量逐渐增大。变性淀粉/聚乙烯醇(PVA)复合膜因良好的生物降解特性而显现出巨大优势。介绍了聚乙烯醇薄膜的性能和改性方法,国内外变性淀粉/聚乙烯醇复合膜的相关研究进展,以及我国目前研究中面临的问题。变性淀粉/聚乙烯醇复合膜不仅可用作包装膜,在抗菌防腐、抗紫外线和保鲜检测方面也展现出不俗的潜力,有望得到广泛应用。     

马铃薯羧甲基淀粉制备工艺的研究

研究了以马铃薯淀粉为原料,用乙醇溶剂法制备羧甲基淀粉（CMS）。探讨了碱化温度、醚化温度、碱化时间、醚化时间、氢氧化钠用量、氯乙酸用量及反应体系中的水分含量对马铃薯羧甲基淀粉取代度（DS）的影响,通过正交试验得出制备马铃薯羧甲基淀粉的最佳工艺条件。     

纳米SiO2改性玉米淀粉/聚乙烯醇复合薄膜研究

以薄膜拉伸强度、断裂伸长率、透光率和吸水率为主要指标,通过单因素试验和正交试验研究纳米SiO2改性玉米淀粉/聚乙烯醇复合薄膜的工艺条件,以改善玉米淀粉/聚乙烯醇复合薄膜的物理性能。试验结果表明:纳米SiO2含量,分散剂种类及含量,膜液pH对膜的性能均有影响。适宜的工艺参数为:纳米SiO2最佳含量2.0%,最佳分散剂聚丙烯酰胺含量1.5%,膜液最佳pH 5.0。     

新型马铃薯羟烷基淀粉的合成及性质研究

以马铃薯淀粉为原料,以环醚在酸性条件下的开环产物为醚化剂,合成了新型马铃薯羟烷基淀粉。应用正交试验和统计分析,确定了一组制备马铃薯羟烷基淀粉的优化实验条件,即在乙醇中,淀粉乳液浓度20%,NaOH用量为干淀粉质量的12%,醚化剂用量为干淀粉质量的18%,45℃反应17h后,产品的最高醚化度为0.1188。性能测试的结果表明,新型马铃薯羟烷基淀粉具有优良的应用性能。     

微波辐射处理对玉米淀粉颗粒非晶化的影响

采用微波辐射的手.段处理原玉米淀粉,考察了分散剂种类,淀粉与分散剂的质量比及微波处理的温度对淀粉非晶化的影响。用偏光显微镜观测处理后淀粉的颗粒结构,结合X射线衍射曲线验证淀粉颗粒结构的变化,利用扫描电镜观測颗粒保持的状态。结果表明:当分散剂为水,淀粉与水分的质量比为3:4时,原玉米淀粉可以均匀的转变为非晶颗粒态淀粉。     

Maximizing alcohol yields from wheat and maize and their co‐products for distilling or bioethanol production

The key to optimizing alcohol production from cereals is a full understanding of the physiology and processing characteristics of different cereals. This study examined the maximum alcohol yields that can be obtained from wheat and maize using different processing technologies. Lower processing temperatures (85°C) resulted in high alcohol yields from wheat (a temperate crop), whereas higher processing temperatures (142°C) gave maximum alcohol yields from maize (a tropical crop). Similar trends were also observed when the spent grains from these cereals were processed using commercial enzymes. Mill settings were additional factors in influencing alcohol production. Wheat has the potential to produce higher alcohol yields when compared with maize, when residual biomass (i.e. spent grains) saccharification using selected commercial enzymes is taken into account. While this approach is not applicable for the Scotch whisky industry owing to strict legislation forbidding the use of exogenous enzymes, this is pertinent for bioethanol production to increase the alcohol yield obtained from both starch and lignocellulosic components of whole cereal grains. Wheat and maize processing temperatures and the use of processing aids are of potential economic benefit to bioethanol producers and to beverage alcohol producers seeking to understand the factors influencing the processing properties of different cereals. Copyright © 2015 The Institute of Brewing & Distilling