大麦芽淀粉碱法提取工艺的研究

以大麦芽为原料,以淀粉提取率为指标,通过碱法提取工艺提取大麦芽淀粉,采用正交试验探讨了搅拌时间、料液比、pH对淀粉提取率的影响,在正交试验的基础上,通过优化得出最佳提取工艺条件为:搅拌时间为3h,料液比为1∶4,pH值为12;在此条件下淀粉的提取率为87.12%。     

Studies on Starch Granules

In X-ray diffractometric studies on starch granules of many kinds of plant species, we found a variety of intermediate C-type patterns. In particular, specimens of sweet potato starch granules varied from nearly the A-type pattern to nearly the B-type pattern. In these studies, we also found that spheroids of short chain amylodextrin showed very sharp diffraction patterns and that we could form amylodextrin spheroids with various types of X-ray diffraction patterns by varying the conditions of recrystallization. Then we showed that the X-ray patterns and physical properties of many kinds of cereal and root starches varied to some extent depending on the environmental conditions prevailing during the growth period. We examined the formation and the growth of starch granules in corn endosperm and the inner structures of these granules from the beginning to the end of their maturation by electron microscopic observations. We proved also, the appositive growth of starch granules using radio-active carbon dioxide. Then we tried to form starch granules in vitro. But the spheroids obtained from solutions of starch components were entirely different from natural starch granules. From the findings in these experiments, an ultramacromolecular concept of the starch granule is proposed.     

Studies on Coleus Starch

Coleus starch was isolated by standard procedure and its properties studied. The granule size varies from 5 to 20 μm with majority being in the range 8–16 μm. The gelatinization temperature is 65–85°C. Viscosity of a 2% solution is 37 s (Redwood No. 1). The viscosity increases to 56 s on cooling and remains steady afterwards. The sol stability of the 2% solution is 72 h. The total amylose content is 33% of which soluble amylose is 12.8%. The sweeling volume is 25 cm³/g of starch the reducing value in terms of ferricyanide number is 2.71. The results are discussed in comparison with other tuber starches.     

Studies on Varagu Starch

Starch has been isolated from the millet varagu in 63% yield. Study of the physical properties revealed: moderate swelling and low solubility power in water; extensive solubility in dimethyl sulfoxide, probably indicative of easy solvent penetration due to labile and heterogeneous bonding forces within the granule. Brabender amylogram indicated little retrogradation on cooling, owing to strong bonding between the linear and branched molecules of starch. The amylose content of the starch was 24% as determined by paper chromatographic fractionation and “Blue value” method.     

Studies on Lentil Starch

A general analysis of Egyptian varieties of lentil seeds and some foreign varieties was carried out. The starch was first quantitatively separated and purified from the seeds and its yield was determined. The amylose and amylopectin, viscosity, chain length and glucoamylase effect were determined.     

机械活化木薯淀粉干法制备羧甲基淀粉的研究

研究了以机械活化60 min的木薯淀粉为原料,采用干法工艺制备羧甲基淀粉(CMS).探讨了机械活化时间、反应时间、反应温度、催化荆用量、醚化剂用量及体系含水量对木薯羧甲基淀粉取代度(DS)的影响.实验结果表明,机械活化对木薯淀粉的羧甲基化反应有显著的强化作用:木薯淀粉的DS随活化时间的延长而增大.活化60 min的样品在条件为反应时间120 min、ClCH2COOH与淀粉的摩尔比0.55、NaOH与淀粉的摩尔比0.55、反应温度60℃、体系含水量18%时制得的CMS的DS为0.88%,而在相同条件下,由原木薯淀粉制得的CMS的DS仅为0.23%.     

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.     

Some Studies on Starch Gelation

The mechanical behaviour of starch gels at small static deformations was investigated. In the concentration range 6 - 30% w/w starch gels behave as Hookean solids with a linear dependence between shear modulus and concentration. At a fixed concentration the shear modulus of starch gel increases in the order potato <maize <pea. The starch gel was considered to be a composite in which swollen gelatinized starch granules reinforce an interpenetrating amylose gel matrix. The factors which influence the mechanical behaviour of this composite are discussed.     

魔芋淀粉改性研究

用魔芋淀粉,氯乙酸和氢氧化钠为原料,在乙醇溶液中制备高粘羧甲基淀粉,用正交试验设计试验考察了物料配比、反应温度和反应时间对产品性质的影响,确定了最佳反应条件。     

Studies on Pyrodextrinization of Corn Starch

During pyrodextrinization of corn starch in the absence of any added catalyst under different experimental conditions, the changes of dextrinization might have two or threes stages and remarkable transformation would begin to occur at 190°C. At higher temperatures, many non-carbohydrates are found. At lower temperatures, side chains of amylopectin-like substances might be cleaved to produce the linear parts.     

酯化淀粉制备方法的研究

本文研究了多种制备酯化淀粉的方法,包括淀粉柠檬酸酯制备方法、淀粉苹果酸酯制备方法和二淀粉磷酸二酯制备方法,对制备条件进行了探索和改进。用傅立叶变换红外光谱仪进行了鉴定和分析,证明了酯基的存在。但是二淀粉磷酸二酯在1300～1250cm-1波数范围内没有发现有明显不同于原淀粉的吸收峰,表明可能仅存在很少量的无法检测到的酯基。用扫描电镜观察到,淀粉粒呈球形或多面体形,表面光滑而且没有发现明显的孔隙或裂缝。用DSC观察到,吸热峰的峰值在105.8℃,在100℃之前,没有任何吸热峰,表明没有糊化。这可能是由于在淀粉粒表面上的淀粉分子通过磷酸根形成交联,将淀粉粒束缚,使淀粉难以糊化。对二淀粉磷酸二酯、淀粉柠檬酸酯和淀粉苹果酸酯的制备条件进行了探索和改进,进一步提高了抗性淀粉产率,探讨了它们的抗淀粉酶消化的机理。与国外的研究相比,本试验使抗性淀粉含量有了很大幅度的提高,最高值为93%左右。     

慈姑淀粉的性质研究

研究了慈姑淀粉性质,结果发现:慈姑淀粉粒多呈圆形,少数椭圆形,粒径范围为4～25μm,平均粒径10μm,X-射线衍射呈C型结晶图样。DSC法测得慈姑的起始糊化温度To=52.330℃,峰值温度TP=68.226℃,终止温度Tc=77.280℃。快速黏度测定仪测得慈姑淀粉的峰值黏度为2363.00mPa.s,最低黏度为1756.00mPa.s。55℃以下,慈姑淀粉的溶解度与膨润力低,糊化后溶解度与膨润力大大提高。与玉米淀粉、木薯淀粉和莲藕淀粉相比,慈姑淀粉糊透明度较低,冻融稳定性较强。     

Studies on Dioscorea rotundata Starch Properties

Starch from six clonal selections of Dioscorea rotundata was isolated by standard procedure. The yield was between 20–24%. Various properties of these starches were compared. Granule size, 2% viscosity, peak viscosity, clarity, sol stability, total and soluble amylose contents were studied and only small variations were observed in the properties except paste viscosities among the clonal selections. The phosphorus content of Dioscorea starch was found to be three times as much as cassava starch, but low compared to potato starch. The higher gel strength of D. rotundata starch paste compared to cassava gel may be attributed to the phosphate linkages among the starch molecules in the granules.     

酶法转化淀粉合成海藻糖的初步研究

海藻糖是一种新型多功能食品添加剂,目前其主要生产方法是以淀粉为底物进行酶法转化,本报道了从中国土样中筛选分离到的一株可产生相关酶的细菌的培养特性及初步鉴定结果。同时,对利用该菌株产生的酶转化淀粉合成海藻糖的反应条件进行了初步探讨。     

抗性淀粉的结构及生理功能研究

综述了抗性淀粉(RS, resistant starch)的结构研究进展.现有的研究表明,RS2属于B型结晶,糊化后成为B和B型的混合物;RS3由糊化后的淀粉在冷却或储存过程中缓慢地重新结晶而形成,描述RS3结晶结构的模型有束状模型和层状模型.天然淀粉糊化后,在低温下老化处理形成B型结晶,在高温下老化则形成混合型结晶或形成A型结晶;RS4为化学变性淀粉,其大量衍生基团的存在在空间上防碍了酶-底物复合物的形成.     

两性淀粉研究进展

两性淀粉是一种重要变性淀粉产品,用途广泛,具有优良应用性能;该文介绍我国变性淀粉发展新领域,两性淀粉合成与反应原理、产品性能、应用领域等,并展望今后应用发展前景。     

Studies on Starch Extracted from Mango Seeds (Mangifira indica) as a New Source of Starch

The aim of this research was to find a new source of starch that can be used mainly in the industrial field easily and economically. The yield of mango seeds was about 21% of starch. Amylase treatments proved that the extracted product form mango seed was starch. Chemical and physical starch characteristics were determined, and microscopic studies were carried out to study starch molecules and granules. Results indicated that the pure starch was similar in its characteristics to tapioca starch. Viscosity data of the pure mango seed starch were little lower than with the other starches as well as its solubility being higher.     

Suspension Studies on Granular Starch Slurries

An inspection of the required impeller speed to maintain minimum suspension of granular starch in baffled vessels was carried out. The types of impellers studied are the marine propeller, the straight blade turbine and the pitched blade turbine. The study shows that the impeller off-bottom distance is an important parameter for all types of impeller studied.     

Studies on the Biosynthesis of Starch Granules. Part 9. The Starch Granules from Wrinkled-Seeded Peas

The nature of the complex granules of wrinkled-seeded pea starch has been examined, and related to changes in the starch during growth. An earlier hypothesis for the development of pea starch is shown to be untenable in the light of this information, and possible alternative mechanisms for the biogenesis of pea starch are discussed.