经丙烯酸共聚物改性的淀粉糊的流变性能的研究

采用溶液聚合法合成了三元丙烯酸酯共聚物（MA／BA／AA）。红外光谱和X－射线衍射分析了共聚物的组成,并探讨了该共聚物与淀粉反应的过程。结果表明,该共聚物在淀粉颗粒上进行自由基接枝共聚反应,反应主要发生在淀粉颗粒的无定形区,改性后的淀粉能够保持原淀粉颗粒的完整结构。     

淀粉丙烯腈接枝共聚物及其皂化物的颗粒结构特性

使用扫描电子显微镜、偏光显微镜和Ｘ－ｒａｙ衍射分析仪,研究了淀粉、淀粉丙烯腈接枝共聚物（ＳＰＡＮ）及其经碱皂化后的产物ＨＳＰＡＮ的颗粒形貌结构和晶体特性。结果表明：ＳＰＡＮ仍具有类似于淀粉颗粒形貌的颗粒结构;同时,低接枝百分率的ＳＰＡＮ接枝反应主要发生在淀粉颗粒的非结晶区,但随着接枝百分率的提高,接枝共聚反应逐渐向淀粉颗粒内部结晶区渗透,淀粉颗粒的结晶区逐渐被破坏,当接枝百分率高于５４．８９％时,原淀粉颗粒的半结晶性基本上被完全破坏;而ＨＳＰＡＮ为非晶体结构。     

接枝淀粉浆料干法接枝反应的研究

为探讨新型接枝淀粉浆料(能替代PVA用于涤棉纱上浆)的制法,在干法条件下制备了接枝淀粉浆料.研究了反应温度、引发剂用量、反应时间及接枝单体用量对接枝淀粉接枝率、接枝效率和接枝单体转化率的影响.结果表明:ω(引发剂)=2%(对淀粉质量)、ω(接枝单体)=50%(对淀粉质量),35℃反应3.5 h条件下,可以得到接枝率和接枝效率均佳的接枝淀粉;扫描电镜(SEM)显示有聚合物接枝到淀粉颗粒表面;结构分析表明发生了共聚反应,产物为丙烯酸、丙烯酰胺、丙烯酸丁酯与淀粉的接枝共聚物.     

Promozyme脱支化处理后对淀粉-丙烯酰胺接枝共聚影响

该文报道Promozyme进行玉米淀粉脱支化工艺条件研究,得出影响脱支化因素重要性顺序,在此基础上选用三种直链淀粉含量不同淀粉乳与丙烯酰胺进行接枝共聚反应。结果表明,其聚合速率、接枝率均高于原淀粉,随着直链淀粉含量增加,单体聚合率和接枝率呈现增加趋势;用扫描电镜观察,其接枝产物结构形态比较均匀,无明显两相界面,且淀粉-丙烯酰胺接枝共聚物絮凝效果优良。     

淀粉-丙烯酸接枝共聚物耐盐性能研究

研究了淀粉-丙烯酸接枝共聚物的耐盐性及其改进方法.实验结果表明:淀粉-丙烯酸接枝共聚物的糊料中加入5%无水硫酸钠黏度保留值为68.5%;共聚时加入一定量的丙烯酸十八酯可以提高共聚物的耐盐性;用羟丙基淀粉代替原淀粉的共聚产物对提高耐盐性效果更明显,取代度越高耐盐性能越好;用羟丙基淀粉代替原淀粉,同时加入丙烯酸十八酯的共聚产物耐盐性能更好.用取代度0.2的羟丙基淀粉,在丙烯酸十八酯用量为丙烯酸的2%的条件下合成共聚物,在其糊液中加入5%无水硫酸钠,黏度保留值可达93.1%.     

丙烯酸酯单体结构对接枝淀粉上浆性能的影响

探讨丙烯酸酯单体结构对烯丙基醚化预处理型淀粉-丙烯酸-丙烯酸酯接枝共聚物上浆性能的影响。通过将烯丙基醚化淀粉与丙烯酸及具有不同分子结构的丙烯酸酯类单体进行接枝共聚合反应,制备出一系列具有不同接枝支链分子结构的接枝淀粉。采用该系列接枝淀粉对涤棉混纺纱进行上浆试验,测试了浆纱的强伸性能、耐磨性和毛羽数。结果表明:当选择丙烯酸乙酯为接枝单体时,所制备的接枝淀粉浆出的涤棉混纺纱性能较好。认为:烯丙基醚化淀粉-丙烯酸-丙烯酸酯接枝共聚物可适宜于涤棉混纺纱的上浆。     

非晶颗粒态玉米淀粉的制备及接枝共聚改性

以玉米淀粉为原料,采用乙醇溶剂一高温加热制备了非晶颗粒态玉米淀粉,通过X-射线衍射和偏光显微镜研究了非晶颗粒态玉米淀粉的结晶性质与颗粒形貌;以中和的丙烯酸为单体,过硫酸铵为引发剂,N,N'-亚甲基双丙烯酰胺为交联剂,对非晶颗粒态玉米淀粉进行接枝共聚改性,制备出具有高吸水性的接枝共聚物,并对其吸水性能做了研究,其吸水率和吸盐水(0.1%NaCl)率分别为590.1g/g和232.6 g/g;用扫描电子显微镜、红外光谱对其进行结构表征.     

接枝淀粉及其在纺织上的应用

甲基丙烯酸甲酯／丙烯酸丁酯的接枝共聚反应是用过氧化物-亚铁离子氧化还原系统，在淀粉上接枝苯乙烯。在60℃时进行接枝，苯乙烯／甲基丙烯酸甲酯和苯乙烯／丙烯酸丁酯的单体比率重量百分比为80／20，50／50，20／80。本文研究了影响接枝效率的引发剂浓度，淀粉浓度，和单体比率。对接枝淀粉做了进一步研究，分析了他们的颗粒大小，体积密度，上过浆的棉纱的物理机械性能，例如断裂时的强力和伸长等。研究在水中和乳化液中淀粉接枝共聚物的流变学性能。     

机械活化预处理对木薯淀粉与丙烯酰胺接枝共聚反应的影响

采用搅拌球磨机对木薯淀粉进行机械活化,以不同活化时间的木薯淀粉为原料、过硫酸铵-亚硫酸氢钠为引发剂、丙烯酰胺为单体制备淀粉接枝共聚物,分别考察机械活化时间、反应时间、引发剂浓度、单体浓度及反应温度等因素对木薯淀粉与丙烯酰胺接枝共聚反应的影响。结果表明,机械活化30 min的木薯淀粉与丙烯酰胺接枝共聚反应的适宜工艺条件为反应时间60 min,淀粉浓度0.37 mol/L,单体浓度1.52 mol/L,过硫酸铵浓度3.0mmol/L,亚硫酸氢钠浓度6.0 mmol/L,反应温度60℃时,接枝率和接枝效率分别为145.1%、85.0%,而原淀粉（预糊化）在相同条件下,接枝率和接枝效率分别为100.3%、60.2%。表明了机械活化预处理对木著淀粉的接枝共聚反应有显著的强化作用。     

乳液聚合法和微波法制备淀粉与苯乙烯接枝共聚物比较

分别采用乳液聚合法和微波法制备淀粉与苯乙烯接枝共聚物,对其接枝参数进行比较,并利用红外光谱、扫描电子显微镜等测试手段对接枝共聚物微观结构进行分析比较,确定乳液聚合法和微波法制备淀粉与苯乙烯接枝共聚物为同一物质;通过比较得出乳液聚合法接枝百分率和接枝效率高于微波法,而微波法节约时间和能源。     

Rheological and textural properties of sorghum-based formulations modified with variable amounts of native or pregelatinised cassava starch

Sorghum bread was made from native or pregelatinised cassava starch and sorghum flour in the ratio 10:90, 20:80, 30:70, 40:60 and 50:50. The other ingredients, measured on flour-weight-basis, were water (100%), sugar (6.7%), egg white (6%), fat (2%), salt (1.7%) and yeast (1.5%). The dynamic oscillatory behaviours of the batters were affected by the amount and type of starch. In the amplitude sweep measurements, increasing concentration of native starch decreased storage modulus, whereas increasing concentration of pregelatinised starch increased the linear viscoelastic range of the batters. In the frequency sweep measurements, the loss factor of batters treated with native starch declined with increasing frequency. Batters treated with 10 or 20% pregelatinised starch showed declining loss factors, whereas batters treated with 40 or 50% pregelatinised starch showed increasing loss factors with increasing frequency. Sorghum-based batters containing native starch gave bread with better crumb properties than batters containing pregelatinised starch. Crumb firmness and chewiness declined with increasing native or pregelatinised starch concentration. Crumb adhesiveness of breads containing pregelatinised starch increased with increasing starch content but was not affected by native starch. Cohesiveness, springiness and resilience increased with increasing native starch content, but were minimally affected by increasing pregelatinised starch content.     

淀粉类对低温乳化香肠品质的影响

以鸡肉和猪肉为主要原料,采用肥瘦肉分离斩拌法制备低温乳化香肠,研究原淀粉及其变性淀粉对低温乳化香肠保水保油性、质构和感官品质的影响。结果表明:在7种淀粉中,添加原淀粉如玉米淀粉和木薯淀粉的乳化肠保水保油性最差,而添加玉米交联酯化淀粉和木薯交联淀粉(SH50)的乳化香肠的保水保油性最好;对低温乳化香肠质构改善作用最优的为木薯交联淀粉(SH50),其次为玉米交联酯化淀粉、马铃薯醋酸酯化淀粉(P0170)、木薯醋酸酯化淀粉(T0170)、木薯淀粉、玉米淀粉、复合变性淀粉(DURAT010)。添加木薯交联淀粉(SH50)的乳化香肠感官评分最高。     

三偏磷酸钠高交联玉米淀粉非糊化特征研究

研究了以三偏磷酸钠为交联剂制备非糊化的高交联玉米淀粉的方法，测定了反应的取代度和布拉班德粘度曲线，提出高交联玉米淀粉与原淀粉颗粒不同，在沸水只发生轻微溶胀，呈非糊化颗粒态。     

Relationship between thermomechanical properties and baking expansion of sour cassava starch (Polvilho azedo)

The factors involved in the baking expansion of native and sour cassava starch doughs were compared with those of native corn starch. Unlike corn starch dough, native and sour cassava starch doughs showed expansion properties during baking. The storage modulus E ′ decreased for cassava starch doughs before baking expansion, but remained unchanged for corn starch dough. Expansion during the baking of sour cassava starch was attributed to water vaporisation and the fluidity of starch paste. The fact that temperature and weight loss variations at adequate water contents were significantly greater for cassava than corn starch dough is indicative of the important role played by starch melting in expansion. Expansion ability could be correlated with changes in dough–crumb thermomechanical properties when close to the starch melting temperature. © 2001 Society of Chemical Industry     

变性淀粉在午餐肉中的应用效果研究

将木薯变性淀粉与玉米原淀粉在午餐肉中的应用效果进行了对比,结果表明,添加了变性淀粉的产品在弹性、组织状态、口感及贮存稳定性方面明显优于玉米原淀粉。     

Influence of Phosphate Esters on the Annealing Properties of Starch

The effects of annealing on native potato, waxy maize, and phosphorylated waxy maize starches were compared. Phosphorylated waxy maize starch responded to annealing in a manner between that of the naturally phosphorylated potato starch and that of the native waxy maize starch. The gelatinisation end-point temperature was increased, whereas in the native waxy maize it was decreased. On the other hand, the onset temperature change was much larger in potato starch than in the two waxy maize starches. Steeping also yielded intermediate effects on the phosphorylated waxy maize starch. It was concluded that the phosphate groups have similar effects as they do in the native, naturally phosphorylated potato starch, although the substitution pattern is not entirely the same in the artificially phosphorylated starch.     

Effect of oxidation and esterification on functional properties of mung bean (Vigna radiata (L.) Wilczek) starch

The chemical and physicochemical properties of mung bean starch oxidized by sodium hypochlorite and esterified with succinic anhydride were studied. Mung bean starch was modified by oxidation with sodium hypochlorite and esterified with succinic anhydride. The native mung bean starch (NMBS) granules were shown to have an irregular shape, which varied from oval to round to bean shape with a smooth surface. Succinylation led to partial rupture of the granule integrity while oxidation converted the smooth surface of the native granules to a surface with fissures. Swelling capacity improved through succinylation but was reduced after oxidation. Oxidation enhanced solubility; however, succinylation showed no uniform effect throughout the temperature range studied. Both modifications increased hydrophilic tendency and demonstrated decreased gelatinization temperature compared to the NMBS. Oil absorption capacity and syneresis of native starch was enhanced after oxidation but was reduced after succinylation. Both starch types, native and modified, exhibited non-Newtonian behavior, but to a different extent. The gel formation of oxidized starch revealed the highest storage modulus followed by native starch and then succinated 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.     

α-淀粉酶水解对芭蕉芋淀粉理化性质的影响

目的酶法水解为芭蕉芋淀粉进行改性,提高芭蕉芋淀粉的应用价值,扩大于其在食品工业的应用范围。方法以芭蕉芋淀粉为原料,采用α-淀粉酶水解制备酶解淀粉,结合热失重(TGA)技术考察α-淀粉酶水解对芭蕉芋淀粉热稳定性和其他理化性质的影响。结果与原淀粉相比,酶解淀粉的溶解度和膨胀度、吸水度和吸油度增大;透光率和冻融稳定性降低;TGA结果表明,α-淀粉酶水解不改变芭蕉芋淀粉的组成成分,且酶解芭蕉芋淀粉的分解温度较高,表明其热稳定性增加。结论通过α-淀粉酶酶解法可制备满足工业需要的改良芭蕉芋淀粉。     

Functional Properties and Retrogradation of Heat‐Moisture Treated Wheat and Potato Starches in the Presence of Hydroxypropyl β‐cyclodextrin

Some functional and retrogradation properties of native and heat‐moisture treated potato and wheat starches were examined in the presence of hydroxypropyl β‐cyclodextrin (HPβ‐CD). HPβ‐CD increased swelling factor, amylose leaching, and solubility of both native and heat‐moisture treated wheat starches but it had less impact on corresponding potato starches. Gelatinization enthalpy of native wheat starch was decreased in the presence of HPβ‐CD but was increased in potato starch with increasing concentration. Reduction of amylose‐lipid complex endotherm in both native and heat‐moisture treated wheat starch was observed in the presence of HPβ‐CD. Heat‐moisture treatment did not change the transition parameters of amylose‐lipid complex showing its resistance to hydrothermal treatment. HPβ‐CD greatly decreased the pasting temperature of wheat starch. Cold paste viscosity of both native and heat‐moisture treated wheat starch was increased by HPβ‐CD to a greater extent than corresponding potato starch. Amylopectin retrogradation of all the starches was unaffected in the presence of HPβ‐CD but heat‐moisture treatment slightly decreased retrogradation of potato starch. These results suggest that HPβ‐CD can disrupt the amylose‐lipid complex within the starch granule in both native and heat‐moisture treated wheat starch but has no influence on amylopectin retrogradation. However, greatly increased wheat starch setback with HPβ‐CD indicates its greater effect on wheat starch amylose retrogradation.