玉米淀粉退火处理及其性质变化

采用扫描电子显微镜(SEM)、激光粒度分析仪(LPA)、X射线粉末衍射仪(XRD)和差示扫描量热仪(DSC)研究退火处理对玉米淀粉颗粒形貌、粒径大小、晶体结构和热力学性质的影响。结果显示:退火处理会改变玉米淀粉颗粒的外貌,使其微孔增多,孔径增大;退火处理会增加玉米淀粉颗粒粒径;退火处理不涉及玉米淀粉晶体结构的变化;退火处理会使玉米淀粉糊化温度显著增高,糊化温度范围变窄;原玉米淀粉(NC)和退火处理玉米淀粉(AC)的溶解度和膨胀率都随着温度的升高而增大,在相同温度条件下,退火处理玉米淀粉(AC)溶解度和膨胀率均小于原玉米淀粉(NC)。     

韧化处理对大米淀粉性质的影响

为韧化处理在大米淀粉改性中的应用提供理论依据,作者以余赤早籼米为原料,在不同温度（50～70℃）和水分质量分数（45%～65%）条件下对大米进行韧化处理,然后提取韧化处理后大米中的淀粉,以未经韧化处理提取的大米淀粉为对照,研究韧化处理对大米淀粉溶解度、膨润力、糊化特性、消化特性和冻融稳定性的影响。研究结果表明：与对照组相比,经韧化处理的大米淀粉溶解度和膨润力降低;峰值黏度、最终黏度、谷值黏度、回生值和衰减值均有所降低,糊化温度升高,不同韧化处理温度对衰减值的影响差异显著;淀粉中RDS（快消化淀粉）质量分数升高,RS（抗性淀粉）质量分数减少,SDS（慢消化淀粉）质量分数随着韧化处理条件的不同而不同,说明韧化处理提高了大米淀粉的消化性,也使大米淀粉冻融稳定性下降。     

玉米淀粉磷酸酯糊特性研究

以玉米淀粉为原料和三偏磷酸钠反应，并采用分光光度计、旋转粘度计等现代分析仪器，对生成的玉米淀粉磷酸酯的糊特性进行了较详细的研究，通过流变学分析，测得所得变性淀粉糊均为非牛顿流体。结果表明：交联度较高时，糊的透明度低，但冻融稳定性较好。     

韧化处理对甘薯淀粉糊化特性的影响

本文采用差示扫描量热分析、快速粘度分析等现代仪器分析方法研究了不同韧化时间、韧化温度和含水量等韧化处理方法对甘薯淀粉糊化特性的影响。结果表明,不同韧化温度处理后,甘薯淀粉的起始糊化温度、峰值糊化温度和终止糊化温度均呈升高趋势,其中起始糊化温度升高趋势明显,由甘薯淀粉的62.47℃升高到70.37℃,糊化温度范围变窄,糊化热焓值增加;其峰值黏度呈下降趋势,55℃时为1342 cp比甘薯淀粉下降了321 cp,破损值降低、回生值升高。不同韧化时间处理后,甘薯淀粉To升高,糊化温度范围变窄,由甘薯淀粉的21.35℃减少到60 h的15.09℃,回生值上升了29.89%。不同水分含量韧化处理后,85%时糊化热焓值提高了36.20%,峰值黏度比甘薯淀粉下降了378 cp。甘薯淀粉经韧化处理后糊化温度、热焓值升高,黏度下降,回生值增加。     

Granular Properties of Different Starch Phosphate Monoesters

Different starch types (corn, rice, and potato starch, corn amylose and corn amylopectin) were phosphorylated by reaction with a mixture of mono and disodium phosphate at different molar ratios (mol phosphate/mol anhydrous glucose) under heat and vacuum. The starch granules of the modified and the native starches were microscopically examined for their sizes and morphology. The correlation between the variation in granular size of the modified starches with the extent of phosphorylation and some other physicochemical properties was studied. The granular size was generally increased while the iodine absorption capacity was decreased by phosphorylation. There were strong correlations between the variation in the starch granular size in dependence on phosphorylation and the corresponding changes in some physicochemical parameter of starch, e.g. solubility, swelling and paste clarity. This relationship was most evident in the case of phosphorylated corn amylopectin. Starch granular size can be taken as a quick indicator of the physicochemical properties of the native and modified starches.     

戊二酸木薯淀粉酯的制备及理化性质研究

本文分别制备水相戊二酸木薯淀粉酯(AGAC)和醇相戊二酸木薯淀粉酯(EGAC),使用FT-IR、XRD和SEM进行微观表征,研究两种酯化淀粉的粘度、透明度、流变性、冻融稳定性和抗盐性等理化性质。微观表征的结果显示两种酯化淀粉分子中成功接入了戊二酸基团,两者的晶型均没有发生变化,其整体结构没有受到很大影响,布拉班德粘度仪分析结果表明AGAC的峰值粘度有所提高,同时糊化温度明显降低,EGAC的糊化温度降低,峰值粘度大幅度提高,但粘度稳定性没有提高。AGAC糊液和EGAC糊液的透明度、冻融稳定性和抗剪切力均强于原淀粉,而AGAC和EGAC抗盐性均低于原淀粉,即其热糊稳定性和抗盐性未得到改善。EGAC的透明度高于原淀粉,但低于AGAC;而冻融稳定性、抗剪切能力均略优于AGAC和原木薯淀粉,引入戊二酸基团后,木薯淀粉的透明度、冻融稳定性和抗剪切能力有一定程度的提高。     

Influence of Annealing on Gelatinization Properties,Retrogradation and Susceptibility of Breadfruit Starch (Artocarpus Communis)

Breadfruit starch samples were prepared after annealing at 45–60°C for 24 h and the relationship between the thermal properties and the retrogradation of starch was investigated using differential scanning calorimetry. The peak temperature (T_p) increased with increasing annealing temperature but enthalpy value was decreased with increasing annealing temperature. Twelve days after storage, according to the Avrami equation, the retrogradation rate of annealed breadfruit starch that estimated by the change of re-gelatinization enthalpy of starch was slowed when compared with the control. Furthermore, annealing treatments strongly affected the susceptibility of starch to enzymatic hydrolysis. These results showed that the increasing of T_p breadfruit starch by differences of annealing treatments could retard the retrogradation and resistant of breadfruit starch to enzymatic hydrolysis.     

Physicochemical Properties of Different Types of Starch Phosphate Monoesters

Different types of starch were phosphorylated to different degrees of substitution using monosodium and disodium hydrogen orthophosphate at 160 °C under vacuum. Generally, phosphation enhanced the physicochemical properties of the modified starches compared to their native counterparts. Solubility and swelling power greatly increase when phosphorylation was carried out to a low degree of substitution, while the solubility and swelling power decreased gradually by increasing the degree of substitution. However, the values of the monoesters were still higher than those of the corresponding native polysaccharides. Viscosities of different starch types except corn amylose showed the highest values at the lowest degree of substitution, when the degree of phosphation increased the viscosity values decreased. Native potato starch formed a clear paste (96% transmittance) due to the presence of phosphate groups while the paste clarity of potato starch decreased gradually by increasing the degree of phosphation. Generally, phosphorylation increased the light transmittance of the other starches investigated at the lowest degree of substitution but the clarity decreased by increasing the degree of substitution.     

Effect of Phytate and Other Myo-inositol Phosphate Esters on α-Amylase Digestion of Starch

The effects of phytate and other myo-inositol phosphate esters (containing one or more phosphate groups) on α-amylase digestion of soluble potato starch were evaluated by an in vitro procedure. Human salivary or Bacillus subtilisα-amylase was treated with either 2 mM or 5 mM phytate, myo-inositol-2-monophosphate (l–2-MP), or phytate hydrolyzed to various degrees, and then incubated at 37°C with the starch at pH 4.15 or 6.90. Starch digestion varied with degree of phosphorylation of inositol, inositol phosphate ester concentration, pH and enzyme source. At pH 4.15, phytate (2 mM) and I-2-MP (2 mM) reduced starch digestion by salivary α-amylase to 8.5 and 78.3%, respectively, of the control.     

辐照对淀粉黏度特性影响的研究

采用^60Coγ-射线对玉米淀粉进行辐照处理,辐照剂量分别为2kGy、4kGy、6kGy、8kGy和10kGy．然后对不同辐照剂量的淀粉样品测定其黏度热稳定性、冷稳定性、凝沉性、凝胶性等黏度特性指标。结果表明：辐照后淀粉的最高热黏度变小,当辐照剂量在4kGy以上时,其最高热黏度基本稳定在15MPa·s左右。黏度冷稳定性有所提高,黏度热稳定性降低,但其凝胶性和凝沉性没有随着放置时间的延长出现规律性变化。     

酶促合成肉豆蔻酸淀粉酯的性质及结构表征

为提高淀粉的反应活性,采用氢氧化钠尿素法对马铃薯原淀粉进行处理,以处理后的马铃薯淀粉和肉豆蔻酸为原料,Novozyme 435为催化剂,在无溶剂体系中制备了取代度为0.018~0.065的肉豆蔻酸淀粉酯,并对其部分理化性质进行研究。结果表明:与原淀粉相比,预处理淀粉溶解度和透明度显著增加(P0.05),其膨胀度、冻融稳定性、乳化性和乳化稳定性均显著降低(P0.05)。同时,肉豆蔻酸淀粉酯的性质与其取代度密切相关,与原淀粉相比,随着取代度的增加,酯化淀粉冻融稳定性、乳化性和乳化稳定性随之升高,而其溶解度、膨胀度和透明度随之下降。扫描电子显微镜(SEM)、傅里叶红外光谱分析(FTIR)、疏水性测定对预处理淀粉及不同取代度的肉豆蔻酸淀粉酯进行观察、测定、分析,结果表明,淀粉颗粒结构被破坏,酯化淀粉具有较好的疏水性,FTIR验证了预处理淀粉及酯化淀粉的生成。     

Some Properties of Cross-bonded Phosphate Diester of Waxy Maize Starch

Phosphate diesters of waxy maize starch were prepared by crossbonding reactions using various concentrations of phosphorus oxychloride (POCl₃) under conditions of controlled pH and temperature in order to have the modified starch with better functional properties. The waxy maize starch treated with 350 ppm POCl₃ (D. B.) showed higher paste viscosity and better heat resistance and acid proofing at a range of pH 3.0–4.0 than the unmodified starch and the other diesters prepared using 250–1,000 ppm POCl₃. The viscosity at 25°C of 4% pastes, added salt, sugar and acid simulating a kind of brown sauce and cooked at 95°C for 10 min, containing the diester prepared by either 350 or 1,000 ppm POCl₃, was higher and more stable in a refrigerator up to 4 months than that of the unmodified waxy maize starch. Application of the diester (1,000 ppm POCl₃) to an effective thickener for “instant Miso soup” was also investigated.     

等离子体活化水韧化处理对蜡质玉米淀粉和玉米淀粉结构及性能的影响

本文研究了等离子体活化水（plasma-activated water,PAW）协同韧化处理对蜡质玉米淀粉（waxy maize starch,WMS）和玉米淀粉（maize starch,MS）结构及性能的影响。结果表明,与常规韧化处理相比,PAW韧化没有改变WMS和MS的结晶类型,但降低了相对结晶度。WMS的相对结晶度从37.1%降低到25.9%,MS的相对结晶度从30.3%降低到27.7%。PAW韧化没有使淀粉分子产生新的官能团,但导致WMS和MS的短程有序性降低。PAW韧化降低了WMS和MS的糊化焓（WMS:13.33~12.10 J/g、MS:10.76~10.26 J/g）、峰值黏度和黏弹性,提高了淀粉糊的凝胶强度。PAW协同韧化处理提供了一种淀粉双重物理改性的新方法,在淀粉基凝胶领域具有潜在的应用。     

甘薯淀粉磷酸单酯理化特性的研究

研究了正磷酸盐为酯化剂制备的甘薯淀粉磷酸单酯的理化特性和结构特征。结果表明甘薯淀粉磷酸单酯的糊透明度、溶解度和膨润力都增大，冻融稳定性明显增强，凝沉性减弱；酯化反应不仅发生在无定形区，而且也破坏了淀粉分子的结晶区，红外光谱分析证实，酯化反应在原来的淀粉分子链上增加了新的基团。     

磷酸酯化对甘薯淀粉凝沉性质的影响

对甘薯淀粉的磷酸酯化制备条件及产物的凝沉性质进行了系统研究，结果表明，甘薯淀粉磷酸单酯的最适制备工艺为：NaH2PO4：Na2HPO4=3：l；反应温度130℃～140℃：反应时间2～3h，pH5．5～6．0，催化剂用量为淀粉千基重的4％～6％。甘薯淀粉经过磷酸酯化反应后可能在脱水葡萄糖单元上引入了磷酸基团，从而导致了淀粉凝沉性质的变化，使得淀粉糊的凝沉趋势降低，透明度增高，冻融稳定性提高。     

大米淀粉及其不同取代度磷酸酯淀粉的糊化和流变特性

粳米淀粉与磷酸二氢钠发生酯化反应,通过改变反应温度得到取代度分别为0.028、0.049、0.073和0.14的磷酸酯淀粉。使用快速黏度分析仪和流变仪对比测定粳米淀粉及具有不同取代度的磷酸酯淀粉的糊化和流变特性。快速黏度分析仪测定的糊化特性显示PO43-与淀粉的结合降低了淀粉的糊化温度,升高了淀粉的峰值黏度,与粳米淀粉相比,磷酸酯淀粉更不易回生。流变仪测定的流变特性显示高取代度的磷酸酯淀粉抗剪切,随着取代度的增加,凝胶硬度降低,凝胶黏性增强。     

Experimental and Modeling Studies on the Synthesis and Properties of Higher Fatty Esters of Corn Starch

This paper describes a systematic study on the synthesis of higher fatty esters of corn starch (starch laurate and starch stearate) by using the corresponding vinyl esters. The reactions were carried out in DMSO using basic catalysts (Na₂HPO₄, K₂CO₃, and Na‐acetate). The effect of the process variables (vinyl ester to starch ratio, catalyst intake, reaction temperature and type of the catalyst) on the degree of substitution (DS) of the starch laurate and starch stearate esters was determined by performing a total of 54 experiments. The results were adequately modeled using a non‐linear multivariable regression model (R²≥0.96). The basicity of the catalyst and the reaction temperature have the highest impact on the product DS. The thermal and mechanical properties of some representative product samples were determined. High‐DS products (DS = 2.26‐2.39) are totally amorphous whereas the low‐DS ones (DS = 1.45‐1.75) are still partially crystalline. The thermal stability of the esterified products is higher than that of native starch. Mechanical tests show that the products have a tensile strength (stress at break) between 2.7–3.5 MPa, elongation at break of 3–26%, and modulus of elasticity of 46–113 MPa.     

大米淀粉及其磷酸酯的理化性质研究

对大米淀粉进行酯化,通过改变温度得到不同取代度的大米淀粉磷酸酯,使用扫描电子显微镜、质构仪、快速黏度分析仪、流变仪对大米淀粉及其不同取代度的淀粉磷酸酯的理化性质进行了测定。结果显示:大米磷酸酯淀粉的硬度、回复性、胶性和咀嚼性要低于大米原淀粉,凝聚性和黏着性要高于原淀粉,取代度越大硬度、回复性、胶性和咀嚼性越小,凝聚性和黏着性越大;大米淀粉磷酸酯的开始糊化温度要小于大米原淀粉,峰值黏度、最低黏度、最终黏度、崩解值、消减值要小于大米原淀粉,取代度增大,开始糊化温度降低,峰值黏度、最低黏度、最终黏度、崩解值、消减值增大。大米淀粉经过磷酸酯变性后,黏度增加了,不易回生,稳定性加强了,凝沉性减弱了,且取代度越高,这些性质越明显;大米淀粉磷酸酯和大米淀粉属于剪切稀化流体,在相同剪切速率下,取代度越大的大米淀粉磷酸酯表观黏度越大。     

磷酸酯淀粉的半干法合成工艺及其性能研究

以木薯淀粉为原料,混合磷酸盐Na2HPO4/NaH2PO4为酯化剂,采用半干法合成出了磷酸酯淀粉.考察酯化剂用量、催化剂用量、磷酸盐配比及反应温度、时间等因素对产品取代度及反应效率的影响.结果表明:半干法合成磷酸酯淀粉的较佳工艺为:反应温度150%,反应时间2 h,磷酸盐用量8%,磷酸盐配比1:1,催化剂尿素用量4%,此时产物的取代度为0.034,反应效率达到80.0%.布拉班德曲线显示磷酸酯淀粉的糊化温度随取代度的增加而降低,而峰值黏度远高于木薯原淀粉.     

阳离子交联淀粉黄原酸酯的制备研究

以天然淀粉为原料,以环氧氯丙烷为交联剂,制备交联淀粉,在此基础上,以GTA为醚化剂、二硫化碳为酯化剂,制备了阳离子交联淀粉黄原酸酯。实验结果表明:交联淀粉的操作工艺条件影响因素顺序为:氢氧化钠用量环氧氯丙烷用量反应时间反应温度;阳离子交联淀粉黄原酸酯的操作工艺条件影响因素顺序为:二硫化碳用量反应时间反应温度氢氧化钠用量,其最佳工艺条件为氢氧化钠加入量20 m L,反应温度40℃,二硫化碳加入量5 m L,反应时间2h。含6.0μg/m L Cr6+的模拟废水经阳离子交联淀粉黄原酸酯处理后,其最小吸光度为0.1892,此时Cr6+最大清除率可达62%以上。