高取代度羧甲基淀粉制备研究

羧甲基淀粉 (CMS)是重要的变性淀粉之一 ,用途广泛。本文研究了以玉米淀粉为原料 ,用乙醇溶剂法制备羧甲基淀粉。探讨了固定淀粉用量(0 5摩尔 ) ,一氯醋酸 (氯乙酸 )用量 ,氢氧化钠用量 ,反应体系水分含量 ,反应温度及反应时间对玉米羧甲基淀粉取代度 (DS)的影响     

高取代度羧甲基淀粉制备研究

羧甲基淀粉（CMS）是重要的变性淀粉之一，用途广泛。本文研究了以玉米淀粉为原料，用乙醇溶剂法制备羧甲基淀粉。探讨了固定淀粉用量（0.5摩尔），一氯醋酸（氯乙酸）用量，氢氧化钠用量，反应体系水分含量，反应温度及反应时间对玉米羧甲基淀粉取代度（DS）的影响。     

非晶颗粒态玉米淀粉制备羧甲基淀粉

以非晶颗粒态玉米淀粉、氯乙酸为主要原料,用乙醇溶剂法制备羧甲基淀粉。研究了反应温度、时间、氯乙酸、淀粉乳浓度、水分含量对样品取代度(DS)的影响。结果表明:在淀粉乳浓度20%,n(氯乙酸):n(淀粉) =1:4,n(NaOH):n(淀粉)=1:2,乙醇溶剂含水30%条件下,55℃反应4h得到较高取代度的羧甲基淀粉。     

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。     

制备荞麦羧甲基淀粉的研究

研究了以荞麦淀粉为原料，用乙醇溶剂法制备荞麦羧甲基淀粉(CMs)。探讨了淀粉乳浓度、一氯乙酸用量、氢氧化钠用量、反应体系水分含量、反应温度和反应时间对荞麦羧甲基淀粉取代度(Ds)的影响，通过正交试验，确定制备荞麦羧甲基淀粉最优工艺条件。     

交联甘薯羧甲基淀粉的制备及影响因素的研究

以甘薯淀粉为原料,用乙醇作溶剂,用环氧氯丙烷作交联剂,氯乙酸作羧甲基化试剂,合成交联-羧甲基复合变性淀粉.研究了氢氧化钠、氧乙酸、反应温度、反应时间、乙醇用量等因素对反应的影响.以取代度为目标,用正交实验法确定了交联-羧甲基复合变性甘薯淀粉合成工艺的最佳条件为:反应温度50℃,反应时间4h,配料比m(淀粉):m(氯乙酸):m(氢氧化钠):1:0.48:0.52,在该优化条件下,交联甘薯羧甲基淀粉取代度(DS)达0.75.     

制备荞麦羧甲基淀粉的研究

本研究以养麦淀粉为原料，用乙醇溶剂法制备荞麦羧甲基淀粉(CMS)。探讨了淀粉乳浓度、一氯醋酸用量、氢氧化钠用量、反应体系水分含量、反应温度和反应时间对荞麦羧甲基淀粉取代度(DS)的影响。通过正交试验，确定制备荞麦羧甲基淀粉最优工艺条件。     

红薯淀粉羧甲基化改性研究

以红薯淀粉为原料 ,用乙醇溶剂法制备羧甲基淀粉 ,通过正交实验探讨了影响羧甲基淀粉取代度的各种因素 ,获得制备条件为 :红薯淀粉用量 10 g、氢氧化钠 7g、氯乙酸 6g、乙醇浓度 75 %、乙醇体积 75mL、碱化温度 35℃、醚化温度 4 5℃、碱化时间 4 5min、醚化时间 80min。在该优化条件下 ,红薯羧甲基淀粉取代度(DS)达 0 .87,粘度达 0 .5 1Pa·S。     

羧甲基绿豆淀粉合成工艺研究

以绿豆淀粉为原料,一氯乙酸作为醚化剂,乙醇为溶剂,制备羧甲基绿豆淀粉。以20 g绿豆淀粉为基准,采用正交和单因素试验对制备工艺进行优化,探讨氢氧化钠用量、一氯乙酸用量、醚化温度、醚化时间对产品取代度影响。试验结果表明,其最佳制备工艺条件为:氢氧化钠用量(氢氧化钠/淀粉摩尔比)1.3、一氯乙酸用量(一氯乙酸/淀粉摩尔比)1.0、醚化温度52℃、醚化时间120 min;在此条件下,制得羧甲基绿豆淀粉取代度为1.05。     

回归正交法优化羧甲基玉米淀粉制备工艺

以玉米淀粉为原料,优化制备羧甲基玉米淀粉工艺条件.以羧甲基玉米淀粉取代度为指标,用正交试验考察制备工艺的影响因素,再用回归正交试验优化制备工艺.结果表明:制备CMS最佳的工艺条件为乙醇浓度95%、乙醇用量60mL、氢氧化钠用量0.263mol、一氯乙酸用量0.117mol、碱化温度35℃、反应温度51.3℃、反应时间90min,在此条件下可制得取代度为0.71的CMS.     

A Comparison of Some Methods for the Determination of the Degree of Substitution of Carboxymethyl Starch

The degree of substitution (DS) markedly affects the properties of sodium carboxymethyl starch (Na‐CMS). In this work Na‐CMS samples with different DS starting from both potato and corn starch were synthesized in an ethanol/water mixture and their DS was determined using three methods: direct titration of the acid form of the carboxymethyl starch (H‐CMS), Cu salt precipitation and back titration. It was found that direct titration gave smaller DS values, while the Cu salt precipitation method gave higher DS values than the back titration method, which was found to be the most accurate. The values of the DS obtained by these methods were similar for lower DS while for higher values the discrepancy was more pronounced. Under the same experimental conditions the CMS obtained from corn starch had a higher DS than the one obtained from potato starch and on average, the discrepancies between the DS values obtained by the employed analytical methods were smaller for the CMS samples synthesized from corn starch.     

Synthesis of Carboxymethyl Starch

Carboxymethyl starch (CMS) was obtained under heterogeneous conditions as a product of the reaction of starch and monochloroacetic acid (MCA) in the presence of sodium hydroxide. The influence of the composition of the reaction mixture, the reaction time and temperature and the type of starch being carboxymethylated on the degree of substitution, DS, and limiting viscosity number, [η], was studied. The reaction temperature influenced the DS values, the highest values of the DS being obtained when the carboxymethylation was performed at 58 °C. Increase of the molar ratio of NaOH to anhydroglycose units leads to an increase in DS, but only to certain extent. The values of the DS and [η] of CMS increased almost linearly with increasing MCA amount in the reaction mixture. The reaction mixture changes caused by adding water to ethanol influenced the DS values of the obtained CMS samples, the maximum DS value being obtained for CMS sample synthesized in ethanol with 25% (v/v) water.     

Highly Substituted Carboxymethyl Starch

Carboxymethyl starches (CMS) with a degree of substitution (DS) in the range of 0.5 to 1.5 and reagent yields about 70% were synthesised under heterogeneous reaction conditions. Starting from a standard procedure for manufacturing low substituted CMS the molar ratios of the reagents were increased. Under these conditions starch particles agglomerated during the reaction and the stirrer stopped. The reaction conditions (pulp density, addition of dispersing and water binding agents, pressure, sequence of reagents addition, reaction time, temperature, starch variety, etc.) were varied to find the best process conditions for optimum reaction efficiencies and product properties. If an amylose‐free starch, e.g. waxy corn starch is used as starting material, the obtained products are completely soluble in water to form a clear solution. The products are good viscosity regulators. Using a 2% aqueous solution a wide range of viscosity (1–90 000 mPa s) can be adjusted. The calcium‐binding capacity and the biodegradability of the products were investigated.     

Development and Physicochemical Characterization of New Resistant Citrate Starch from Different Corn Starches

Resistant starch has drawn broad interest for both potential health benefits and functional properties. In this study, a technology was developed to increase resistant starch content of corn starch using esterification with citric acid at elevated temperature. Waxy corn, normal corn and high‐amylose corn starches were used as model starches. Citric acid (40% of starch dry weight) was reacted with corn starch at different temperatures (120–150°C) for different reaction times (3–9 h). The effect of reaction conditions on resistant starch content in the citrate corn starch was investigated. When conducting the reaction at 140°C for 7 h, the highest resistant starch content was found in waxy corn citrate starch (87.5%) with the highest degree of substitution (DS, 0.16) of all starches. High‐amylose corn starch had 86.4% resistant starch content and 0.14 DS, and normal corn starch had 78.8% resistant starch and 0.12 DS. The physicochemical properties of these citrate starches were characterized using various analytical techniques. In the presence of excess water upon heating, citrate starch made from waxy corn starch had no peak in the DSC thermogram, and small peaks were found for normal corn starch (0.4 J/g) and Hylon VII starch (3.0 J/g) in the thermograms. This indicates that citrate substitution changes granule properties. There are no retrogradation peaks in the thermograms when starch was reheated after 2 weeks storage at 5°C. All the citrate starches showed no peaks in RVA pasting curves, indicating citrate substitution changes the pasting properties of corn starch as well. Moreover, citrate starch from waxy corn is more thermally stable than the other citrate starches.     

交联羟丙基羧甲基复合改性玉米淀粉的性能研究

以玉米淀粉为原料,利用乙醇溶剂法进行羟丙基醚化改性,再采用环氧氯丙烷交联剂和一氯乙酸进行处理而制得复合改性淀粉。采用傅里叶变换红外谱仪、X射线衍射仪和扫描电镜等对玉米原淀粉、羟丙基淀粉、交联羟丙基淀粉、羟丙基羧甲基淀粉和交联羟丙基羧甲基淀粉的微观结构进行了表征。红外分析表明改性淀粉在1287 cm-1处出现羟丙基的吸收峰,同时在1328~1603 cm-1处出现了-COO-吸收峰,说明原淀粉已接入了羟丙基和羧甲基基团。利用X-射线衍射分析改性淀粉仍属A型衍射图,证实了反应主要发生在无定形区。复合变性前后淀粉的表观形貌变化,证实了淀粉其反应不仅发生在淀粉颗粒表面,也发生在淀粉颗粒内部。讨论了改性淀粉的理化性质,结果表明交联羟丙基羧甲基淀粉具有良好的透明性、冻融稳定性、流变性。     

羧甲基淀粉钠的合成与表征

研究了羧甲基淀粉钠(CMS)在合成过程中反应条件对产品取代度的影响,对淀粉和CMS进行了IR谱图的表征,并通过电镜扫描比较了淀粉和CMS的微观颗粒特征。     

水相中高取代度低黏度羧甲基淀粉的制备

羧甲基淀粉(CMS)是一种阴离子淀粉醚,广泛应用于医药、食品、纺织、石油钻探等领域。以玉米淀粉为原料,采用酸化-醚化复合变性的方法在水相中制备高取代度低黏度羧甲基淀粉(CMS),探讨了酸化时间、液固比、NaOH用量、ClCH2COOH用量、醚化反应时间、反应温度对羧甲基化过程的影响,研究发现,对原淀粉进行酸化,可以在不增加其它反应试剂用量的基础上提高产物的取代度(DS),但是酸化时间不应过长。同时得到了其他单因素变化时各自对产物取代度的变化趋势,为进一步优化反应条件提供了依据。     

The Role of Reaction Parameters on the Preparation and Properties of Carboxymethyl Cassava Starch

The role of reaction variables on carboxymethylation of cassava starch was investigated using a statistically experimental design approach. The reaction was carried out in an isopropanol‐water mixture at 40°C for 3 h. The reaction parameters under investigation included water fraction in the reaction medium, the ratio of sodium hydroxide to anhydroglucose unit (AGU) and the ratio of sodium monochloroacetate (SMCA) to AGU. The dependent responses were degree of substitution (DS) of CMS and the reaction efficiency (RE) of the carboxymethylation. Carboxymethyl cassava starches with DS in the range of 0.01 to 0.86 were prepared. The result from regression analysis indicated that the most important factors in controlling the DS of CMS were sodium hydroxide and SMCA contents followed by water content. Response surface plots suggested that the optimal levels of sodium hydroxide and water content to achieve CMS with high DS were at the intermediate values. Similar effects of sodium hydroxide and water content were also observed on the RE while SMCA content had a negative effect; increasing SMCA content resulted in lower RE. The optimal conditions to achieve the highest DS and RE were found to be at a water content of 17–19% with a molar ratio of sodium hydroxide to AGU of 1.8–1.9 and a molar ratio of SMCA to AGU between 1.1–1.5. Carboxymethyl cassava starch with various DS was also prepared. The properties of CMS as affected by the degree of modification were also discussed.     

糯玉米羧甲基淀粉在速冻水饺中的应用

本文从糯玉米中提取淀粉进行羧甲基化变性得到糯玉米羧甲基淀粉，并将糯玉米羧甲基淀粉与普通玉米羧甲基淀粉和普通玉米淀粉在速冻水饺中的应用效果进行对比。对不同品种的淀粉的应用效果和冻藏稳定性进行实验，并分别作一般感官检验和模糊综合评定。二种评定方法的综合结果表明，添加0．9％糯玉米羧甲基淀粉的水饺在色泽，口感，混汤，冻融性质等低温冷藏稳定性方面明显优于对照。