乌冬面专用变性淀粉及其结构表征

采用交联―酯化―预糊化复合变性制备乌冬面专用改性淀粉,并与木薯原淀粉、交联淀粉及交联―酯化淀粉进行比较。结果表明,交联淀粉偏光显微及颗粒形貌没发生明显变化,交联变性并未破坏淀粉结晶结构;交联―酯化淀粉颗粒出现粘连和聚集现象,部分颗粒表面出现凹陷和裂纹现象;红外光谱表明,交联―酯化―预糊化复合变性淀粉在1 728 cm–1、1 247 cm–1附近出现新的吸收峰,分子内引入乙酰基团,X–射线衍射光谱显示,交联―酯化―预糊化复合变性淀粉在5.6°和22°处衍射峰强度减弱,A型特征峰加强,结晶类型由"C"型向"A"型转变;交联―酯化淀粉经预糊化处理后,淀粉颗粒膨胀破裂,结晶结构受到彻底破坏,淀粉偏光十字消失,但预糊化处理未破坏淀粉分子化学键。     

酯化交联淀粉反应及性质的研究(Ⅱ)——糊粘度曲线

测定了三氯氧磷变性木薯淀粉制得的酯化交联淀粉糊的粘度性质 ,如糊的粘度曲线、抗剪切和抗酸碱的特性。变性淀粉的交联度和取代度是影响其糊粘度性质的内在因素     

交联微孔甘薯淀粉理化特性研究

以三氯氧磷为交联剂、耐高温α-淀粉酶-糖化酶混合酶为酶解剂,采用交联-酶解法制备得交联微孔甘薯淀粉。FT-IR红外光谱证明,交联反应发生在淀粉颗粒的-OH、-CO基团上,为酯化交联,结构强度明显增强。此种交联微孔甘薯淀粉较之原淀粉,吸水率、吸油率、抗老化性、抗剪切性、抗酸性和冻融稳定性均有较大提高。     

三氯氧磷交联淀粉生物降解过程中形貌和结晶结构的变化

利用扫描电子显微技术和多功能偏光显微技术系统研究三氯氧磷交联淀粉在生物降解过程中的颗粒形貌和结晶结构变化情况.结果表明：随着交联度的增大,颗粒被微生物破坏的程度变小.经三氯氧磷高交联后的木薯淀粉在微生物降解过程中颗粒的偏光十字变化不明显,表明一定程度的三氯氧磷交联会抑制微生物对淀粉颗粒的作用.     

酯化交联淀粉反应及性质的研究(Ⅰ)——反应历程

研究三氯氧磷变性淀粉的反应 ,实验表明在水相的反应经酯化、交联和水解等历程 ,分别生成磷酸一、二淀粉酯。反应的历程和程度同作用条件有关 ,其中反应的 pH的影响最大。     

辛烯基琥珀酸交联淀粉酯合成工艺研究

以木薯淀粉为原料,用环氧氯丙烷作交联剂,辛烯基琥珀酸酐作酯化剂,采用湿法工艺合成辛烯基琥珀酸交联淀粉酯.探讨了淀粉乳浓度、反应温度、反应时间、pH和沉降积对辛烯基琥珀酸交联淀粉酯取代度的影响,确定制备辛烯基琥珀酸交联淀粉酯的最佳工艺参数为:淀粉乳浓度35%,酯化pH 8.0,酯化温度35℃,酯化时间3 h.交联淀粉的沉降积对酯化取代度影响较小,在生产中可根据最终产品的用途选用合适沉降积的交联淀粉进行酯化复合变性.复合变性淀粉符合食品行业标准,可以在食品工业中应用.扫描电镜对其结构进行观察显示淀粉中受侵蚀颗粒增多,颗粒表面的小凹痕数量增加.     

三氯氧磷交联木薯淀粉颗粒膨胀历程及溶胀机理研究

利用木薯淀粉与三氯氧磷的交联反应,通过控制交联反应程度,成功地控制了交联淀粉颗粒的膨胀并使其停留在不同的溶胀阶段,详细地研究了处在不同溶胀阶段的三氯氧磷交联木薯淀粉颗粒的结构特征和变化趋势,揭示了三氯氧磷交联木薯淀粉颗粒的具体的膨胀历程及溶胀机理,即木薯淀粉是“花蕾绽放式”膨胀历程。     

用差示扫描量热法研究高交联非糊化淀粉的物态性质

用差示扫描量热法（DSC技术）对高交联非糊化玉米淀粉和高交联非糊化木薯淀粉，在水分散体系中随温度的升高而发生的物态变化进行了研究，结果表明三氯氧磷高交联变性淀粉，尽管已经失去了糊化的性质而保持颗粒状态，但在相应的原淀粉糊化温度范围内，仍然发生了由多晶态向非晶态的相转变。     

交联改性对多孔淀粉的性质影响研究

以玉米多孔淀粉为原料,三氯氧磷为交联剂制备酯化交联多孔淀粉,利用扫描电子显微镜、布拉班德黏度仪、X-射线衍射等分析仪器对原淀粉、多孔淀粉和酯化交联多孔淀粉的理化性质、流变学性质和微观结构进行分析比较研究。结果表明,经交联处理后的交联多孔淀粉仍是A型图谱,晶形未发生改变,交联多孔淀粉的吸水率、吸油率与原淀粉和多孔淀粉相比有较大提高,冻融稳定性、糊稳定性优于原淀粉和多孔淀粉,交联改性提高了多孔淀粉的结构性能。     

三氯氧磷交联程度对木薯淀粉体外消化性能和抗消化淀粉形成的影响(英文)

利用体外消化模型对不同交联度的三氯氧磷交联木薯淀粉的消化速度和抗消化性能进行了研究。研究结果表明,三氯氧磷交联木薯淀粉被唾液α-淀粉酶消化的速度随交联度的增大而降低。高交联降低淀粉颗粒和淀粉糊的消化速度,低交联增大淀粉颗粒的消化速度但对淀粉糊的消化速度影响程度较小。同时用Megazyme全淀粉分析盒分析了三氯氧磷交联反应对木薯淀粉抗消化性能的影响。三氯氧磷交联木薯淀粉被酶水解的程度随交联程度的增大而降低,且所含的抗消化淀粉的总量也随着交联程度的增大而减少。高交联特别是使淀粉达到非晶化时淀粉的抗消化性能越强。但是在交联度小于1.71×10-2的范围内,凝沉的交联淀粉消化程度随着交联程度的提高而增大,当交联度继续增大时消化程度则降低。通过控制淀粉的交联程度可以调节淀粉与酶反应的敏感程度和反应活性,从而影响淀粉的营养特性。     

植酸改性淀粉性质的研究

本文对植酸改性淀粉的糊性质进行研究，为其应用提供依据。用X-衍射、电镜、红外光谱等手段对植酸改性淀粉进行研究，表明用植酸钠对淀粉改性时，反应发生在颗粒的表面；脱水葡萄糖的C6伯醇羟基易与植酸钠反应；由淀粉碘复合物的可见光谱图推测支链淀粉最先起反应。     

Effects of Granule Sizes on Physicochemical Properties of Cross‐linked and Acetylated Wheat Starches

Large and small wheat starch granules were used for cross‐linking and acetylation to determine effects of granule sizes on physicochemical properties of the modified starches. The native and cross‐linked starches from the small granules showed higher phosphorus contents than did those from the large granules. However, the level of phosphate substituents in the modified starches was not significantly different between the large and small granules under the same conditions. In contrast, the large granules had a higher reactivity with acetic anhydride than did the small granules. The phosphate group cross‐linked starch (CS), acetylated starch (AS) and acetylated cross‐linked starch (ACS) from the large granules had lower gelatinization temperatures and higher enthalpies than those from the small granules. The paste viscosities of the CSs from the large granules decreased rapidly, whereas those of the AS or ACS increased significantly as compared with those from the small granules. The pastes of cross‐linked starches from the small granules were more stable than those from the large granules, whereas the pastes of AS and ACS from the large and small granules had similar resistance to freeze‐thaw treatment. Scanning electron microscopy (SEM) also showed that the small granules were less damaged after modification than the large ones. Thus, the different granule sizes resulted in different physicochemical properties of starch after modification.     

戊二酸蜡质玉米淀粉酯的制备及理化性质研究

以原蜡质玉米淀粉为原料,戊二酸酐为酯化剂,乙醇为反应溶剂制备戊二酸淀粉酯(EGAS)。采用傅里叶变换红外光谱（FT-IR）、扫描电子显微镜（SEM）、X射线衍射仪（XRD）及布拉班德粘度仪等对样品进行表征及理化性能分析。结果表明：FT-IR显示戊二酸淀粉酯在1730 cm-1处和1565 cm-1处出现了新的吸收峰,其中1730 cm-1处为C=O的伸缩振动吸收峰,1565 cm-1处为游离的-COO-的反对称伸缩振动吸收峰,表明了淀粉分子中成功接入了戊二酸基团;改性前后淀粉的表观形貌变化,证实了反应不仅发生在淀粉颗粒表面,也发生在淀粉颗粒内部;XRD分析显示改性后的淀粉仍属于A型结晶结构,表明了反应主要发生在无定形区;布拉班德粘度分析则表明了改性后的淀粉（DS=0.0450）峰值粘度提高了2.33倍;EGAS的冻融稳定性和抗剪切力均强于原淀粉,糊的透明度得到改善。     

交联微孔淀粉的制备及其性能研究

以木薯淀粉为原材料,三氯氧磷（POCl3）为交联剂,糖化酶与α-淀粉酶为复合酶,采用一次法和两次法制备了交联微孔淀粉.测定了交联微孔淀粉的吸水率和吸油率,利用扫描电子显微镜（SEM）和X射线衍射（XRD）对交联微孔淀粉进行了性能表征.结果表明：与一次法相比,两次法制备的交联微孔淀粉吸附能力提高了很大的提升,当POC13用量为0.4μL/g时,吸水率和吸油率分别增加了9.22％和10.43％.SEM观察到交联微孔淀粉表面有较多孔洞,微孔化程度高;XRD结果发现交联微孔淀粉的结晶度降低.     

Chemical and Physical Characterisation of Grain Tef [Eragrostis tef (Zucc.) Trotter] Starch Granule Composition

Chemical and physical properties of starch granules isolated from five grain tef (Eragrostis tef) varieties were characterised and compared with those of maize starch. Endogenous starch lipids extracted with hot water‐saturated n‐butanol and total starch lipids extracted with n‐hexane after HCl hydrolysis were 7.8 mg/g (mean) and 8.9 mg/g (mean), respectively, slightly lower than in the maize starch granules. The starch phosphorus content (0.65 mg/g) was higher than that of maize starch but virtually the same as reported for rice starch. The starch granule‐swelling factor was lower than that of maize starch and extent of amylose leaching was higher. The starch X‐ray diffraction pattern was characteristic of A type starch with a mean crystallinity of 37%, apparently lower than the crystallinity of maize starch and more similar to that reported for rice and sorghum starches. The starch DSC gelatinisation temperature was high, like for other tropical cereals; T_o, T_p, T_c and ΔH were in the range 63.8—65.4, 70.2—71.3, 81.3—81.5 °C and 2.28—7.22 J/g, respectively. The lower swelling, apparently lower percentage crystallinity and lower DSC gelatinisation endotherms than maize starch suggest that the proportion of long amylopectin A chains in tef starch is smaller than in maize starch.     

Effect of phosphoric acid treatment on physicochemical,functional, and structural properties of starch extracted from yam (Dioscorea rotundata)

This work was designed to elucidate selected physicochemical, functional, and structural properties of native and modified yam (Dioscorea rotundata) starch. The isolated starch was chemically modified using 5, 10, 15, 20, and 25% phosphoric acid solution at 50°C for 1 h, and yield, swelling power, gelation, water holding capacity, paste clarity, blue value, and amylose and amylopectin content of the native and modified yam starch were determined. Structural changes in the native and starch modified with 25% phosphoric acid were evaluated using Fourier transform infrared spectroscopy and optical microscopy. The result showed that the yield, swelling power, water holding capacity, paste clarity, blue value and amylose and amylopectin content of native yam starch was 33.38% (217 g), 3.84 g/g, 1.0 v/g, 10%, 0.52 and 25.96, respectively, whereas gelation study of the native and modified starch indicated that native starch was viscous and modified starch firm. However, yield, swelling power, water holding capacity, paste clarity, blue value, and amylose content of modified yam starch reduced in a dose dependent manner with phosphoric acid. The reduction in the values of the various functional properties could be associated with the effect of phosphoric acid on the starch granular structure. The result of Fourier transform infrared spectroscopy and optical microscopy revealed that the yam starch was modified by phosphoric acid with changes in functional groups spectra such as –OH stretch (3177 cm^?1), H₂O absorbed (1644 cm^?1) (amorphous region), C-H stretch (2923 cm^?1), CH₂O (1253 cm^?1), and C-O-C (1078 cm^?1) when compared to native starch. The morphology of native and modified yam starch granules ranged from oval to eliptical. However, modified starch granules were rough in surface. In conclusion, the characterized physicochemical and functional properties and structure exhibited by native and modified yam starch indicated that, yam could be a cheap and valuable source of starch for industrial application.     

磷酸酯Gemini表面活性剂的结构与性能

通过以P2O5和POCl3为磷化剂,合成2种不同结构的磷酸酯Gemini表面活性剂,并对其结构和表面活性、润湿性、乳化性、泡沫性、抗静电性、摩擦特性之间的关系进行讨论。结果表明:磷酸酯Gemini表面活性剂具有较好的表面活性和应用性能;磷化剂为P2O5的Gemini表面活性剂,其表面张力、润湿性能、对纤维的平滑性较好,而以POCl3为磷化剂的Gemini表面活性剂的乳化性、低泡性、抗静电性、抱合性较好。     

The Starch of Pueraria tuberosa — Comparison with Maize Starch

Pueraria tuberosa starch was isolated from the tuber and purified. Scanning electron microscopy of the starch showed polygonal shaped granules which were almost of the same particle size as those of maize starch. P. tuberosa starch has lower amylose content, almost same gelatinization temperature range and water binding capacity, more swelling and solubility compared to maize starch. Paste viscosity characteristics show high peak viscosity but also indicate fragile nature of granules in comparison to maize starch.     

Internal Plasticization of Granular Rice Starch by Hydroxypropylation: Effects on Phase Transitions Associated with Gelatinization

The effects of hydroxypropylation on phase transitions associated with gelatinization of granular rice starch were studied by differential scanning calorimetry. At a 1:1 starch/water ratio, a progressive shift of the biphasic gelatinization endotherms to lower temperatures as well as a broadening and shortening of the G endotherm with increasing molar substitution were observed, indicating increased internal plasticization and destabilization of the amorphous regions of the starch granules. The overall enthalpy of gelatinization was also reduced. Hydroxypropyl groups, which are attached to starch molecules primarily in the amorphous regions of the starch granules, behave as flexible side chains. The motion of these side chains creates a large amount of free volume, thereby lowering the glass transition and crystallite melting temperatures associated with starch gelatinization. The modified starch granules may thus be viewed as internally plasticized polymer resins which are more easily gelatinized than the unmodified starch.