盐酸水解制备木薯微孔淀粉的研究

利用盐酸水解制备木薯微孔淀粉。研究盐酸浓度、反应时间、反应温度对微孔淀粉吸附性能的影响,并通过扫描电镜（SEM）、比表面积研究（BET）、热失重分析（TGA）等手段研究微孔淀粉的结构。结果表明：盐酸处理木薯淀粉后形成微孔,且木薯微孔淀粉的比表面积远远大于木薯淀粉的比表面积。盐酸水解木薯淀粉的最优化工艺为：4.0%HCl、反应温度45℃、反应时间为8h。     

盐酸制备小麦微孔淀粉的性能及结构研究

利用盐酸制备小麦微孔淀粉,研究盐酸浓度、反应时间、反应温度和搅拌速度对微孔淀粉吸附性能的影响,并通过红外光谱(IR)、差示扫描量热分析(DSC)、X射线衍射分析(XRD)研究微孔淀粉的结构.结果表明:盐酸制备小麦微孔淀粉的最佳工艺条件是:盐酸浓度4.0%,反应时间16h,反应温度45℃,搅拌速度为1500r/min.通过XRD、DSC分析发现:小麦微孔淀粉的结晶部分比例增加.     

高吸油性木薯微孔淀粉复合酶法的制备工艺

研究木薯微孔淀粉复合酶法的制备工艺,以吸油性能为指标,通过单因素和正交正交试验,研究淀粉乳浓度、复合酶用量、复合酶的配比、反应体系pH值、反应温度和反应时间等因素对木薯微孔淀粉吸油性能的影响.复合酶法生产木薯微孔淀粉的最佳工艺条件:底物浓度60%,酶用量2.5%,α-淀粉酶和糖化酶酶活力配比为1:5,pH为6.0,反应温度60℃,反应时间7 h,所得木薯微孔淀粉的吸油率和比表面积比原淀粉分别提高了53%和54%.     

微孔淀粉的半干法制备条件及其理化特性研究

研究小麦微孔淀粉的半干法制备及理化特性。考察了反应温度、加酶量、加水量、pH值、反应时间5个因素对制备微孔淀粉吸油率的影响。通过正交试验得到了半干法制备小麦微孔淀粉的最佳工艺参数,即:反应温度52℃、pH5.5、加水量30%、加酶量1 600U/g、反应时间12h,在该条件下制得的微孔淀粉的吸油率为17.2%。同时也考察了小麦微孔淀粉的理化特性,包括流变学特性、糊的透明度、冻融稳定性;结果表明,小麦微孔淀粉比天然淀粉具有优良的糊稳定性和冻融稳定性好,可为小麦微孔淀粉的工业化生产提供参考。     

红薯微孔淀粉的制备及性质研究

以红薯淀粉为原料，探讨α-淀粉酶用量、反应温度、反应pH值和反应时间等因素对其微孔化反应的影响，并对微孔淀粉的吸水率、吸油率和X射线衍射以及扫描电子显微镜结构表征进行了研究。     

半干法制备蜡质玉米微孔淀粉工艺条件的优化

研究半干法制备蜡质玉米微孔淀粉的工艺条件。以蜡质玉米淀粉为原料,淀粉吸油率为评价指标,考察反应温度、加酶量、加水量和反应时间4个因素对蜡质玉米微孔化的影响。结果表明蜡质玉米微孔淀粉半干法制备的最佳工艺条件为反应温度51℃,加酶量1 685 U/g,加水量32%,反应时间11.75 h,在该条件下制得的微孔淀粉的吸油率为13.54%。研究得出了半干法制备蜡质玉米微孔淀粉的最佳工艺参数,为工业化生产提供了参考数据。     

甘薯微孔淀粉制备技术及吸附性能研究

用淀粉糖化酶、α-淀粉酶、普鲁兰酶水解甘薯淀粉制备一种具有吸附功能微孔淀粉载体。研究表明,淀粉糖化酶对生甘薯淀粉作用力最强;淀粉糖化酶水解制备甘薯微孔淀粉最佳工艺条件是:温度45℃,pH值4,酶用量为1％,时间24小时,水解率为51.52％。微孔淀粉对色素、水溶性维生素、油脂的吸附能力远远高于原淀粉。通过交联反应能明显提高微孔淀粉的结构性能和吸附性能。     

复合酶法优化木薯微孔淀粉工艺研究

目的:研究木薯微孔淀粉制备的最佳工艺条件;方法:利用复合酶作用木薯淀粉,采用k(34)正交试验法研究复合酶的用量、pH值、反应温度和反应时间对微孔淀粉吸附性的影响;结果:木薯微孔淀粉制备的最佳工艺:复合酶用量2.0%,pH值5.5,温度50℃,反应时间36 h.木薯微孔淀粉对亚甲基兰溶液、食用油的吸附性比木薯原淀粉明显提高;结论:试验结果可为木薯微孔淀粉的工业化生产提供参考.     

不同配比复合酶协同酶解木薯微孔淀粉的研究

为优化微孔淀粉的制备工艺,采用不同配比复合酶对淀粉进行酶解处理。借助L9（34）正交试验,研究不同的反应条件对微孔淀粉吸附性的影响。试验得出：复合酶处理淀粉后,在木薯淀粉表面形成微孔,且木薯微孔淀粉的比表面积大于木薯淀粉的比表面积。当复合酶中的α-淀粉酶与糖化酶比例为1∶5时,复配效果最佳。该条件下的最优化工艺为：复合酶用量1.0%、反应温度50℃、pH值5.5、反应时间16h。     

酸法优化小麦微孔淀粉的工艺及结构研究

利用盐酸对小麦淀粉进行处理,通过L^9（3^4）正交试验,研究盐酸浓度、反应时间、反应温度和搅拌速度对微孔淀粉吸附性能的影响,并通过示差扫描量热分析（DSC）、X射线衍射分析（XRD）研究微孔淀粉的结构。研究表明：盐酸制备小麦微孔淀粉的最佳工艺条件是：盐酸浓度4．0％,反应时间16h,反应温度45℃,搅拌速度为1500r／min。通过XRD、DSC分析发现：小麦微孔淀粉的结晶部分比例增加。     

绿豆微孔淀粉酶法制备工艺优化研究

以水解率为指标,研究α-淀粉酶与糖化酶复合水解绿豆淀粉制备微孔淀粉工艺条件,通过单因素和正交试验确定酶解最佳工艺条件：α-淀粉酶：糖化酶=1：3,酶用量2．0%,时间20 h,温度42℃,pH4．2。经吸水、吸油率测试,对酶解前后绿豆淀粉进行性质分析表明,微孔淀粉吸水、吸油能力明显大于原淀粉。     

Some Studies on Starch Carbamate

Starch carbamate was prepared by reacting maize starch with urea using solid state technique. The different factors affecting this reaction were studied. These factors include urea concentration, type of starch, reaction and duration. The carbamate extent and carbamation reaction efficiency (%) were traced by estimating the nitrogen content of the reaction product. Solubility, viscosity and total ester content of starch carbamate samples were estimated. The carbamate extent increases by increasing urea concentration as well as reaction temperature and duration. Increasing the reaction temperature and duration has the same effect on carbamation reaction efficiency (%), while increasing urea concentration do the reverse. The solubility (%) of starch carbamate samples depends on urea concentration, reaction temperature and duration as well as the type of starch used. The maximum solubility obtained was 63% and 43% for starch carbamate derived from pregelled and native starch, respectively. Tentative mechanism for the reaction between starch and urea has been proposed.     

Synthesis of high fatty acid starch esters with 1‐butyl‐3‐methylimidazolium chloride as a reaction medium

In this work, high fatty acid esters of corn starch were synthesized by reacting the starch with fatty acid methyl ester using 1‐butyl‐3‐methylimidazolium chloride (BMIMCl) ionic liquid (IL) as reaction media. The effect of reaction variables such as the catalyst amount, molar ratio of fatty acid methyl ester/anhydroglucose unit (AGU) in starch, pyridine/AGU molar ratio, reaction temperature, as well as reaction time on the degree of substitution (DS) of starch esters was investigated. The experimental results showed that the DS value of the obtained starch esters could be varied depending on the process conditions. In the optimum reaction condition, the achieved maximum DS of starch laurate and starch stearate was 0.37 and 0.28, respectively, at a reaction temperature of 110°C for starch laurate and 120°C for starch stearate for a reaction duration of 2 h. Furthermore, the starch esters were characterized by FTIR, SEM, and X‐ray diffractometry (XRD) techniques, respectively. Results from FT‐IR spectroscopy suggested that the hydroxyl groups in the starch molecules were converted into ester groups. SEM and XRD studies showed that the morphology and crystallinity of starch esters were disrupted largely in the IL medium under the reaction conditions.     

干法制备氧化淀粉的工艺研究

以H_2O_2为氧化剂，在碱催化剂存在的条件下干法制备出氧化淀粉。并对反应温度、反应时间、反应体系水的质量分数、NaOH与淀粉的摩尔比和H_2O_2与淀粉的摩尔比对氧化淀粉羧基含量的影响进行了研究。在固定反应时间3h，以及H_2O_2与淀粉的摩尔比0.225的条件下，选择反应温度、反应体系水的含量、NaOH与淀粉的摩尔比为三因素，采用正交实验，确定出制备氧化淀粉的最佳工艺参数为：反应温度60℃、反应体系水的质量分数为26.5％、NaOH与淀粉的摩尔比为0.135。     

Determination of the Degree of Branching in Normal and Amylopectin Type Potato Starch with 1H-NMR Spectroscopy Improved resolution and two-dimensional spectroscopy

Starch from genetically modified potatoes was found to be highly branched compared with normal potato varieties through the use of ¹H-NRM spectroscopy. The average chain length, blue-value, and the wavelength at maximum absorptivity clearly show that the new potato varieties produce amylopectin starch. Correlation between the degree of branching as determined by ¹H-NMR and starch-iodine complexation, expressed as blue-value, was good and the NMR-method gives low standard deviation. For the first time, the anomeric proton, H-1, of a (1→4)-α-linked D-glucose residue and the H-1 of the glucose residue of a non-reducing end have been assigned separate chemical shifts in starch. Assignments were made as determined from two-dimensional homonuclear and ¹H-¹³C heteronuclear spectroscopy (COSY, HMQC, and HMBC). The molecular weight in degraded starch and pullulan were determined by means of NMR-spectroscopy. These results were in accordance with determinations by size exclusion chromatography and with the known molecular weights of pullulan standards.     

正交试验法优化马铃薯氧化淀粉制备工艺

使用正交试验法优化马铃薯氧化淀粉制备工艺,以马铃薯淀粉为原料,FeSO4为催化剂,H2O2为氧化剂干法制备氧化淀粉,并以羧基含量为评价指标,分别考察反应时间、反应温度、氧化剂用量、催化剂用量、体系含水量等因素对马铃薯淀粉氧化反应影响。得到最优工艺条件为:反应时间3.5h、反应温度60℃、FeSO4在淀粉中质量分数0.025%、H2O2与淀粉摩尔比0.285、反应体系含水量24.000%,在此条件下制得马铃薯氧化淀粉羧基含量为0.530%。     

氧化淀粉微波酯化及性能研究

本论文以氧化玉米淀粉为原料,以磷酸盐为酯化剂,采用微波作为加热介质制备了氧化淀粉磷酸酯。考察了微波功率、磷酸盐配比、尿素添加量、反应温度和反应时间对制备氧化淀粉磷酸酯性能的影响,并确定了最佳的酯化反应条件为:微波功率为800 W,NaH2PO4/Na2HPO4比例为2∶1,尿素用量为4%,反应温度为140℃,反应时间为30min。制得的氧化淀粉磷酸酯的涂布纸性能优于3S淀粉。     

羟丙基马铃薯淀粉合成工艺及性能研究

本文以马铃薯淀粉为原料，环氧丙烷为醚化剂，氢氧化钠为催化剂对低取代度羟丙基淀粉的制备工艺进行了研究。考察了环氧丙烷用量、氢氧化钠用量、反应时间、反应温度对羟丙基淀粉取代度的影响。实验结果表明，提高环氧丙烷用量、氢氧化钠用量、反应时间和反应温度可提高羟丙基淀粉取代度，硫酸钠用量对羟丙基淀粉取代度有影响。采用分光光度法测定了羟丙基淀粉取代度。     

Chemical Modification of Starch via Reaction with Acrylamide

Reaction of starch with acrylamide was carried out under different conditions including reaction medium, catalyst, acrylamide concentration, reaction time and temperature as well as liquor ratio. Organic solvents, namely, isopropyl alcohol, dimethylformamide and cyclohexane alone and in admixture with water at different ratios were used as reaction medium. Catalysts used include sodium hydroxide, trisodium phosphate, sodium carbonate, sodium benzoate, sodium acetate and sodium formate. Acrylamide concentration ranged from 25% to 200%, based on weight of starch. The reaction was studied over a wide range of temperature and duration. Results obtained showed that the extent of reaction of starch with acrylamide is governed by each of these factors. Furthermore, this reaction yields mixed starch ethers, namely carbamoylethyl starch and carboxyethyl starch. Solubility, viscosity and moisture content of these starch ethers are determined by the sum of the amide and carboxyl contents.     

交联木薯淀粉的干法制备及其性能研究

为了提高交联淀粉的生产效率,以木薯淀粉为原料,三偏磷酸钠为交联剂,采用机械活化辅助干法制备了交联木薯淀粉。以沉降积为评价指标,考察了三偏磷酸钠用量、氢氧化钠用量、反应温度、反应时间、球磨介质堆体积、转速对交联反应的影响。在单因素实验基础上,采用正交试验优化了工艺条件,并对交联木薯淀粉的理化特性和结构进行了表征与分析。结果表明,干法制备交联木薯淀粉的最佳工艺条件为:三偏磷酸钠用量4%,氢氧化钠用量2.5%,反应温度40℃,反应时间60 min,转速380 r·min-1,球磨介质堆体积500 mL,在此条件下制备的交联木薯淀粉沉降积为1.52 mL;FTIR、XRD、SEM进一步证实木薯淀粉发生了交联反应。随着木薯淀粉交联度的增大,木薯交联淀粉较原淀粉透光率、膨胀度、溶解度下降,凝沉性增强,更适应食品工业的发展。