山药淀粉加工特性研究

采用水磨法制备山药淀粉,以马铃薯淀粉和玉米淀粉为对照,比较系统地研究山药淀粉的颗粒特性和糊化特性。结果表明,山药淀粉颗粒多为扁卵圆形,颗粒大小在8～30μm之间,长轴平均粒径为20μm;偏光十字中心偏向一边,呈"X"型。山药淀粉溶解度和膨胀度明显小于玉米淀粉和马铃薯淀粉。与对照相比,山药淀粉糊具有较低的透明度,较差的冻融稳定性。山药淀粉起糊温度较高,糊的热稳定性好,抗剪切能力强。增加淀粉质量分数和pH,淀粉糊冷热稳定性降低。添加蔗糖、NaCl和Na2CO3,提高了山药淀粉的起糊温度,增强热稳定性,提高抗剪切能力,但添加明矾使糊热稳定性降低,抗剪切能力下降。除蔗糖外,NaCl、Na2CO3、明矾添加剂对山药淀粉的糊化特性影响明显。     

山药及零余子酸、酶处理淀粉的理化性质

利用酸和淀粉酶、糖化酶分别处理山药及零余子淀粉,利用扫描电镜、X射线衍射及流变仪等测定不同处理组淀粉的理化特性。结果表明：山药和零余子原淀粉颗粒较为完整,没有裂缝,呈卵圆形,表面光滑;酶、酸处理均会导致淀粉降解,酸处理淀粉表面破坏最为严重;零余子原淀粉、酸处理和酶处理的淀粉结晶度分别为32.02%、27.02%和31.13%,而山药原淀粉、酸处理和酶处理淀粉结晶度分别为34.32%、29.27%、33.55%。淀粉糊透光率、凝沉百分比表明零余子原淀粉最易老化,流变特性表明不同处理组的淀粉均具有弱凝胶特性。     

菠萝蜜种子淀粉颗粒的物化特性研究

利用SEM、X-射线衍射、聚焦光束发射测量仪、Brabender黏度仪、DSC等研究菠萝蜜种子淀粉的物化性质.结果表明,菠萝蜜种子淀粉颗粒多呈半椭圆形,断口为"凹"或者两面斜交形或者三面锥形,在水相中平均粒径为19.5μm;颗粒晶体结构为C型,结晶度为45%;DSC测得To、Tp、Tc分别为65.20、68.81、73.77℃,△Hgel为2.97J/g;起糊温度较高,为81.1℃,热糊稳定性和凝胶性好.     

氧化蜡质玉米淀粉的糊流变特性研究

探讨了氧化蜡质玉米淀粉糊流变性、抗剪切能力以及浓度、温度和剪切速率对表观黏度的影响,并与蜡质玉米淀粉糊进行比较.结果表明:氧化蜡质玉米淀粉糊属于非牛顿流体.浓度、温度、剪切速率对流变性均有影响:在同一浓度和剪切速率下,表观黏度随温度的增加而减小;在同一温度和浓度条件下,淀粉糊的表现黏度随剪切速率的增加而减小;在室温、相同剪切速率下,表现黏度随浓度的增加而增大.氧化蜡质玉米淀粉糊属于剪切稀化体系,抗剪切能力较强.     

小麦淀粉流变学特性分析

研究小麦淀粉流变学特性,对小麦淀粉溶液糊化过程中粘度与剪切速率、温度和浓度关系进行分析,结果显示糊化后小麦淀粉糊为典型假塑性流体,对小麦淀粉糊流变学分析表明,其流变模型用幂函数表示有很高拟合度,以Y表示粘度,X表示剪切速率,浓度8％,90℃时,本实验小麦淀粉模型为y=1319.5x-0.4144,R2=0.9735。     

西米淀粉糊流变特性研究

利用Brookfield旋转粘度计研究西米淀粉糊流变性、抗剪切能力、触变性以及温度、浓度和剪切速率对表观粘度的影响,为西米淀粉在食品行业的应用提供理论上的依据。结果表明:西米淀粉糊属于非牛顿流体。温度、浓度、剪切速率对流变性质均有影响,在同一浓度和剪切速率下,表观粘度随温度的增加而减小;在同一温度和剪切速率下,表观粘度随浓度的增加而增加;在同一温度和浓度条件下,淀粉糊的表观粘度随剪切速率的增加而减小。西米淀粉糊属于剪切稀化体系,抗剪切能力优于马铃薯淀粉糊和木薯淀粉糊;淀粉糊粘度随剪切速率增大的上行线与随剪切速率减小的下行线之间存在滞后圈,说明西米淀粉糊具有触变性。     

黄米淀粉的制备及流变学特性的研究

淀粉的流变学特性是影响工业化淀粉质食品品质的重要因素.本文通过碱法优化提取工艺制备了黄米淀粉产品,分析了黄米淀粉的基本理化指标,并利用Brabender糊化仪和Brookfield旋转黏度仪研究了黄米淀粉的糊化特性、流变特性以及机械剪切触变性能,为黄米淀粉在食品工业的应用提供理论依据.结果表明:黄米淀粉中蛋白质残留量为0.232%,淀粉纯度为88.98%,淀粉得率为58.6%,直链淀粉含量为18.28%,起糊温度为73.9℃;峰值黏度为702BU;与马铃薯淀粉、大米淀粉及玉米淀粉相比,黄米淀粉糊具有较强的黏度冷稳定性以及较弱的凝胶性和凝沉性;黄米淀粉糊属于非牛顿型、假塑性、剪切稀化的触变性流体;在同一剪切速率下,表观粘度随温度的增加而降低;在同一温度下,淀粉糊的表观粘度随剪切速率的增加而减小.     

苦荞淀粉颗粒及淀粉糊性质研究

为明确苦荞籽粒淀粉理化特性,以7个苦荞品种为材料,分析了其淀粉颗粒表面结构及其淀粉糊的透明度、冻融稳定性、凝沉性、糊化特性、热焓特性。结果表明,苦荞淀粉颗粒多为不规则多面体球形,颗粒大小平均为6.8μm;苦荞淀粉糊的透明度平均为7.68%,低于玉米淀粉糊;苦荞淀粉糊凝沉性、冻融稳定性均强于玉米淀粉糊;苦荞淀粉的峰值黏度、谷值黏度、最终冷黏度、破损值及回生值均高于玉米淀粉;苦荞淀粉糊具有较强的热黏度稳定性、冷黏度稳定性和凝胶形成能力;苦荞淀粉糊的平均糊化温度范围为65.87℃到78.41℃,峰值温度为70.88℃,均低于玉米淀粉糊。     

凝胶淀粉的理化特性研究

用凝胶淀粉中试产品进行理化特性分析:包括粘度测定、热糊与冷糊稳定性;不同pH值、糖、盐存在下淀粉粘度曲线与凝胶强度以及冻融稳定性;颗粒形貌、红外光谱和X-射线分析等。结果表明:本品是一种易分散于冷水,加热易糊化成均匀透明胶体液,其热、冷糊稳定性高;在低或高pH值范围内,用糖或不用糖,不用硬化用盐类均能胶凝。凝胶强度强,尤其耐酸性特好;冻融稳定性增强,保水性亦好;凝胶淀粉与天然淀粉颗粒形貌几乎没有差别,表明交联、水解反应只在淀粉颗粒的表面进行。晶体结构也未发生变化。     

紫薯淀粉理化性质的研究

以制得的紫薯淀粉为原料,研究了紫薯淀粉的化学组分、颗粒表面结构、结晶结构、凝胶质构、热力学性质和流变学特性,并与马铃薯淀粉、玉米淀粉和甘薯淀粉进行比较.结果显示:干基紫薯淀粉含量为98.78％,直链淀粉含量为19.74％;其淀粉颗粒平均粒径为17μm,属中粒淀粉,晶型为C型;淀粉凝胶弹性和咀嚼性高,硬度适中,为3.095×102 g,黏着性适中,为24.72 g·s;糊化温度范围为61.5℃到78.0℃,峰值温度为72.6℃;紫薯淀粉糊为有屈服应力的非牛顿型流体.     

淀粉预处理方法对多孔淀粉的影响

多孔淀粉的制备原料有玉米淀粉、木薯淀粉、马铃薯淀粉等。在制备过程中,淀粉原料某些性质的变化对多孔淀粉性质有一定影响,不同原料、或同一原料的不同处理方式都会影响多孔淀粉的形成。有效的预处理方法对改变淀粉原料的性质,提高多孔淀粉的生产效率,降低生产成本,改善多孔淀粉的性质十分重要。     

Biosynthesis of starch; identification of potato starch enzymes

Two important starch enzymes, granule-bound starch synthase and branching enzyme, were purified from potato tubers and characterized by immunological comparison with the corresponding enzymes of other plants. Granule-bound starch synthase was identified as a 60-kd protein homologous to the corresponding enzymes of maize and amaranth; the enzyme was missing in amylose-free potato starch granules. Branching enzyme of potato tubers was purified as a single protein species of 79 kd which appeared to be homologous to maize branching enzyme I, but much less to branching enzymes IIa and IIb.     

Effect of damaged starch on wheat starch thermal behavior

The influence of damaged starch (DS) on gelatinization and retrogradation wheat starch properties was investigated. Samples with different content of DS were obtained and evaluated. DSC was used for monitoring the changes in thermal behavior of the starch samples at different water amounts. Starch thermal transitions were affected simultaneously by DS content and water content. The Flory–Huggins parameters were modified by DS. A significant raise in the T°_m, and x_1–2, and a decrease in ΔH_u was recorded. The AP retrogradation kinetics was evaluated by Avrami model. A significant increase of the AP crystallization rate was observed when DS increased. The results demonstrated the importance of the presence of physically damaged granules on wheat starch properties.     

淀粉类吸附剂--多孔淀粉与环糊精的比较

从制备方法、成孔机理、吸附作用和吸附机理等方面对多孔淀粉与环糊精之间的差异进行了比较,并论述了两者在实际运用中的异同,显示出多孔淀粉良好的应用前景。     

直链淀粉含量对抗性淀粉形成的影响

考察不同直链淀粉含量的高直链玉米淀粉形成抗性淀粉的能力。结果表明:随着直链淀粉含量的增加抗性淀粉含量增大,最高可达20.74%,普通玉米淀粉的抗性淀粉得率仅为9.09%。     

芋头淀粉提取工艺优化及淀粉特性研究

以NaOH为浸泡剂,探讨了料液比、pH、浸泡时间、浸泡温度对芋头淀粉提取率及色泽的影响,并对芋头淀粉特性进行了初步研究。结果显示芋头淀粉提取最佳工艺条件为：pH10.0、浸泡温度25℃、料液比1：3、浸泡时间80min。提取率可达84.82%,淀粉白度高达94.11,优于现有文献报道及市售其它常用淀粉;淀粉特性研究显示,芋头淀粉的体积平均粒度在10μm以下,d（0.5）为14.6μm,稍大于10μm;芋头淀粉具有优良的热稳定性、冷稳定性,凝胶强度和凝成特性等特性。     

Gelatinisation of starch and wheat flour starch—A review

Gelatinisation of wheat starch is reviewed, making comparisons with other starches.Starch in wheat kernel endosperm is briefly described. Various aspects of gelatinisation of starch in water are considered, including swelling and interaction with water before the onset of gelatinisation, increase in consistency during gelatinisation, gelatinisation temperature, types of gelatinised system and gel and paste formation upon cooling. In addition, the traditional rationale of gelatinisation and gelatinisation from the viewpoint of water mobility are discussed.Experimental methods used to study gelatinisation are also reviewed, as are the effects of starch concentration, protein, pentosans, surface active agents, fats, salt and sugars on gelatinisation and shear rate on consistency.     

Utilization of rice starch with gums in Asian starch noodle preparation as substitute for sweet potato starch

Starch noodles were produced using a medium grain rice starch in the presence of various gums, and physical properties of the noodles were compared with sweet potato starch noodle. Pasting viscosity of the rice starch was lower than that of sweet potato starch (830 vs. 1,618 cp as peak viscosity). The peak viscosity, however, was increased by the addition of gums (0.1% based on dispersion), and especially xanthan was the most effective in increasing the peak viscosity (1,478 cp). The cooking loss for the rice starch noodles (1.5 mg/mL), greater than that for the sweet potato starch noodle (0.2 mg/mL), was effectively reduced to 0.8 and 0.9 mg/mL, respectively, by the addition of locust bean gum (LBG) and curdlan. The addition of LBG or gellen gum also increased the hardness of the rice noodles. Aging (extended retrogradation) the noodles was effective in reducing the cooking loss and improving the textural properties of the rice starch noodles. The combination of the gum addition (like LBG) and aging of the rice starch noodle might be useful for utilizing rice starch as a substitute for sweet potato starch in Asian noodle preparation.     

蕨根、葛根和马铃薯淀粉油炸膨化加工性质的比较研究

研究了在蕨根淀粉、葛根淀粉和马铃薯淀粉中添加食盐、碳酸氢钠、蔗糖、油脂后油炸加热效果、物料膨化效果的改变情况。结果表明:由于食盐、碳酸氢钠、蔗糖对淀粉糊化的影响及加热后的特性,随着添加量的增加膨化率变小,膨化过程也相对迟缓;随着糖含量的增加,产品的孔隙状态发生变化,孔隙变形、回缩,产品硬度减小,脆度增大,孔隙率渐大,色泽加深。油脂的添加,对脆度影响较大,但是对于膨化率、色泽的影响不大,添加过多时,口感变差。最佳配比是:食盐2%,碳酸氢钠0.2%～0.5%,蔗糖6%,油脂5%,并添加适量甜味剂以改善口感。     

STMP交联变性对淀粉浆料性能的影响

 为探索适用于淀粉浆料的环保型交联剂,满足经纱上浆中对淀粉浆液黏度热稳定性的要求,替代目前常用的甲醛、环氧氯丙烷等有毒交联剂,本文以木薯淀粉为原料,无毒的三偏磷酸钠（STMP）为交联剂,通过改变 STMP对木薯淀粉的投料比,制备了一系列具有不同交联度（DC）的交联淀粉。研究了交联度对淀粉浆液的黏度、黏度热稳定性、黏附性能、浆膜性能、退浆性以及五日生化需氧量（BOD5）和化学需氧量（COD）的影响。研究结果表明,STMP交联可显著提高淀粉浆料的黏度热稳定性;交联度对淀粉浆液的黏度、黏度热稳定性、黏附性能、浆膜性能及退浆性有显著影响,但对淀粉浆料的生物可降解性影响不大。当采用该交联淀粉用于经纱上浆时,交联度选择在650 AGU/CL为宜。