我国9个品种绿豆淀粉的理化特性研究

研究了我国9个品种绿豆淀粉的部分理化性质及颗粒形态。其总淀粉含量、直连淀粉含量、溶解度及膨胀度范围分别为54.73%～57.99%,40.44%～41.82%,13.72%～17.67%,17.27%～20.55%;采用快速黏度分析仪(RVA)和差示扫描量热仪(DSC)测定这些绿豆品种淀粉的糊化特性和热特性,它们的峰值粘度、谷黏度、崩溃值、最终粘度、回生值、峰值时间和糊化温度范围分别为6064～7149cP,2890～3514cP,2858～3937cP,3640～4651cP,511～1201cP,4.00～4.13min,70.0～71.6℃;糊化起始温度、峰值温度、最终温度,成糊温度范围及热焓值范围分别为57.28～62.37℃,66.48～68.74℃,73.29～75.70℃,11.22～16.31℃,8.24～16.39J/g;绿豆淀粉颗粒尺寸5～30μm,呈肾形、椭圆形、小球形和凸圆形等,其微晶结构在偏光显微镜下得到证实。     

玛咖淀粉与马铃薯、淮山药淀粉的理化性质比较

以马铃薯和淮山药淀粉为对照,研究了玛咖淀粉的化学组分、颗粒形貌、结晶结构、热力学性质、溶解度、膨胀度、糊透明度和冻融稳定性。结果表明,玛咖淀粉颗粒呈现椭圆形或不规则形,颗粒长轴在7.2~15.6μm之间,短轴在5.1~9.8μm之间;其偏光十字呈现垂直交叉,X-射线衍射结晶结构为C型,且在衍射角(2θ)为20°附近有直链淀粉-脂类复合物的特征吸收峰。玛咖淀粉的颗粒形貌和结晶结构与淮山药淀粉相似。玛咖淀粉的糊化温度较马铃薯和淮山药淀粉低,该淀粉糊化的起始温度(To)、峰值温度(Tp)和终止温度(Tc)分别为46.88℃、50.42℃和54.82℃,糊化焓变7.37 J/g。玛咖淀粉的溶解度和糊透明度比淮山药淀粉高,比马铃薯淀粉低;其峰值黏度与山药淀粉相近,显著低于马铃薯淀粉;膨胀度和冻融稳定性均优于马铃薯和淮山药淀粉。玛咖淀粉作为一种淀粉新资源,具有一定的开发价值和广阔的发展前景。     

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。     

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。     

慈菇淀粉的理化性质

慈菇是一种丰富的天然营养保健资源。采用扫描电镜、激光粒度分析仪、X-衍射观察分析慈菇淀粉颗粒的形貌和大小,采用理化方法、快速黏度分析仪分析慈菇和慈菇淀粉的化学组成、淀粉糊的膨胀能力、溶解度、透明度、沉降体积、冻融稳定性、糊化温度等性质。结果表明,慈菇鲜球茎中淀粉湿基质量分数为(20.32±0.40)%;慈菇淀粉颗粒呈椭圆形,80%颗粒的颗径范围为0.5～84μm,平均粒径为21.03μm;结晶构形为A型,结晶度为23.5%;含直链淀粉30.48%,糊化温度为73.65℃,淀粉糊的热浆黏度和最终黏度高,糊稳定性好,但冻融稳定性较差,易老化。     

白栎淀粉的特性

采用X射线衍射仪、粒度仪、差示扫描量热仪(DSC)、分光光度计、质构仪等对白栎淀粉的结构及性质进行研究,并与玉米淀粉进行比较。结果表明:白栎淀粉颗粒粒径较小,平均粒径为3.15μm,结晶结构属A型,直链淀粉含量18.90%,糊化温度为72.3～84.7℃;白栎淀粉溶解性和膨润力高于玉米淀粉;白栎淀粉糊具有透明度低、凝沉性大、冻融稳定性差、黏度小、酶解率较高的特点;质构分析表明白栎淀粉糊凝胶强度较大,质地和口感较好。     

花芸豆淀粉的性质研究

研究测定花芸豆淀粉颗粒、糊及其凝胶等特性。发现淀粉颗粒多呈椭圆的腰形,少数圆形,大颗粒表面有明显轮纹,有呈细长或中心放射状的位于颗粒中部的裂纹;偏光十字清晰,多沿长轴方向拉伸呈X形;线条有少许弯曲,有裂纹的颗粒,其偏光十字多有分叉。粒径范围为10~60μm,平均粒径24μm,呈A型结晶图样,结晶区约56.8%,糊化温度73.7~88.3℃,糊化焓15.8 J/g。淀粉碘复合物可见光吸收光谱的最大吸收波长为607nm,链淀粉相对含量为38.4%。花芸豆淀粉糊的抗剪切能力、凝沉性、冻融性和粘度等特性都与玉米淀粉较相近,糊丝长度小,为1.1 cm。加糖对淀粉凝胶的破裂强度及弹性模量的影响较大。     

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。     

莲子淀粉性质的研究

测定研究了莲子淀粉颗粒及其糊的性质,结果发现莲子淀粉颗粒呈多边形状,偏长,有的呈长条形,象马铃薯,具有清晰的偏光十字,都交叉于颗粒中心;粒径范围为4～30μm,平均12.6μm。其结晶构型为C型,结晶度42.8%,糊化温度在74.8～88.4℃,糊化焓12.5J/g;淀粉碘复合物在615nm有最大吸收,链淀粉的相对含量35.7%,莲子淀粉起糊温度较高,糊抗剪切能力很好,具有较好的热粘稳定性与冷粘稳定性。本文还测定了酸碱、糖盐、硼砂、明矾和单甘酯等组分对淀粉粘度的影响。     

豆薯淀粉的特性研究

对豆薯淀粉的基本特性进行了研究。结果表明:豆薯淀粉的水分含量为13.28%,总淀粉含量为75.76%,直链淀粉含量为21.92%;淀粉颗粒为大多为近圆球形,粒径范围3²2μm,平均粒径为12μm;糊化温度为6522μm,平均粒径为12μm;糊化温度为65⁷5℃,峰值黏度(4241 MPa·s)大于其他淀粉,但最终黏度(2440 MPa·s)小于小麦、玉米和红薯淀粉,大于土豆淀粉;溶解度明显高于其他淀粉,膨润力高于小麦和玉米淀粉,低于土豆和红薯淀粉;糊化淀粉的稳定性较差,易凝沉,冻融稳定性较差;糊化淀粉液稳定后的透明度为85.6%,与小麦、土豆和红薯淀粉相近。     

亚糊化热处理对玉米淀粉-胡椒碱复合物功能特性的影响

为探究在亚糊化温度下胡椒碱负载于玉米淀粉对其结构和理化特性的影响,本研究选用玉米淀粉在60℃下制备亚糊化玉米淀粉-胡椒碱复合物,并通过扫描电镜、快速糊化粘度测定仪、差示扫描量热、傅里叶变换红外光谱和X射线衍射等进行了表征。结果表明,胡椒碱成功负载到亚糊化玉米淀粉上,负载率为39.45%;扫描电镜结果显示淀粉颗粒膨胀的裂隙内部成功负载胡椒碱,粒径从天然玉米淀粉的15.20μm增大到亚糊化玉米淀粉的25.80μm,再到亚糊化玉米淀粉-胡椒碱复合物的81.90μm;胡椒碱的加入降低了亚糊化玉米淀粉的峰值粘度和谷值粘度;复合物红外光谱未产生新的基团或化学键,但胡椒碱的加入增强了玉米淀粉与胡椒碱的分子内和分子间氢键作用;X-射线衍射表明相对结晶度从天然玉米淀粉的23.52%升高到亚糊化玉米淀粉-胡椒碱复合物的28.15%,但是亚糊化处理未改变玉米淀粉的晶型结构;与天然玉米淀粉相比,亚糊化玉米淀粉和亚糊化玉米淀粉-胡椒碱复合物的凝胶焓值显著（P<0.05）降低。亚糊化玉米淀粉负载胡椒碱,胡椒碱的加入对亚糊化玉米淀粉的结构影响较小,但对其理化性质产生了显著的影响,并为淀粉与胡椒碱之间的相互作用...     

球磨-辛烯基琥珀酸酯化槟榔芋淀粉的特性研究

以槟榔芋原淀粉为原料,经球磨和辛烯基琥珀酸酯化制得复合改性淀粉,采用扫描电镜、红外光谱仪、X-射线衍射仪、差示扫描量热仪、快速粘度仪等对其结构和糊化特性进行研究,并与原淀粉、仅酯化和仅球磨的改性淀粉进行比较。结果表明:与原淀粉相比,酯化淀粉颗粒和晶体结构均无明显变化,但红外光谱图在1725、1572 cm-1处出现新吸收峰,糊化温度降低,峰值温度由81.77 ℃降低到78.83 ℃,糊黏度升高,峰值黏度由597.67 mPa·s升高到2066.33 mPa·s;球磨淀粉颗粒破碎明显,晶体结构严重破坏,糊化温度降低,峰值温度为72.14 ℃,糊黏度降低,峰值黏度为296.33 mPa·s。复合改性淀粉颗粒发生熔融、破损严重,取代度由酯化淀粉的0.01756增加到0.01994,酯化程度更高;糊化温度最低,峰值温度为65.69 ℃;糊黏度最高,峰值黏度为5063.67 mPa·s。复合改性淀粉具有更好的低温糊化和增稠特性,应用前景广阔。     

洪泽湖野生红莲子、芡实、菱角中淀粉的理化性质研究

以洪泽湖野生的红莲子、芡实、菱角为原料,采用浸泡法制备3种淀粉,并对3种淀粉的颗粒形貌、大小、结晶结构、热学性质、溶解度、膨胀度、糊化特性、分子大小与分布进行研究。结果表明:野生莲子、芡实和菱角淀粉体积平均粒径分别为11.77,2.15,25.76μm,且颗粒大小均匀。3种淀粉均为A型结晶构型,莲子、芡实和菱角淀粉的晶体度分别为27.1%,23.7%,25.7%。糊化峰值温度分别为76.04,72.37,75.88℃,糊化焓值分别为8.46,5.58,4.63J/g。3种淀粉糊的冻融稳定性较差,易形成局部的微晶束,易凝沉、易回生,均不适合应用于冷冻食品;3种淀粉糊的透明度介于马铃薯淀粉和玉米淀粉之间;3种淀粉的热糊稳定性较好,适用于高温食品的生产。     

Granule structural,crystalline, and thermal changes in native Chinese yam starch after hydrolysis with two different enzymes–α‐amylase and gluco‐amylase

Starch extracted from Chinese yam was characterized by scanning electron microscope (SEM), X‐ray powder diffractometer (XRD), and differential scanning calorimeter (DSC) in the process of enzymatic hydrolysis. Yam starch was digested by α‐amylase and gluco‐amylase for different lengths of time, respectively, and two different enzymatic hydrolysis results were compared. The most notable phenomenon revealed by SEM after α‐amylase hydrolysis was the formation of the cavum in the center of the starch granules, while after gluco‐amylase hydrolysis, the outer layer of the granules was peeled off and then some granules even broke into pieces. The XRD of the two enzyme hydrolyzed starches revealed the crystal type of the starch changed from typical C‐type XRD pattern to the representative A‐type pattern in the process of enzymatic hydrolysis. The above results also demonstrated that the partially B‐type polymorph was more easily degraded than A‐type. The thermal result showed that the modified yam starches by both enzymes exhibited increased peak gelatinization temperatures (T_p) and decreased gelatinization enthalpy (ΔH).     

豇豆淀粉的提取及理化性质研究

以长豇豆籽为原料,采用响应面Box-Behnken分析法优化淀粉提取工艺,并对其形态结构和理化性质进行表征。采用五因素三水平的响应面曲面分析法确定豇豆淀粉提取工艺最佳参数为:NaOH溶液的体积420 mL、浸泡时间17 h、乙醇的体积74 mL、振荡转速167 r/min、振荡时间70 min,此条件下理论提取率为62.13%。提取的豇豆淀粉灰分含量为0.17%,蛋白质含量0.87%,脂质含量0.25%,纤维素1.59%,溶解度0.73%,溶胀度1.85 g/g;扫描电镜图像表明,豇豆淀粉颗粒呈球型或椭球形,粒径大多分布在9~13 μm范围内;傅里叶变换红外光谱与X射线衍射分析分析表明,豇豆淀粉具有较强的结晶结构与相对结晶度,呈现典型C型结晶淀粉形态;热力学分析表明,起始糊化温度（T_o）为73.86 ℃,峰值温度（T_p）为80.59 ℃,结束温度（T_c）为88.53 ℃。结果表明豇豆淀粉具有紧密的空间结构与较强的抗糊化性质,在食品质构改良剂等领域有较好的应用发展潜力。     

碾轧对绿豆淀粉的机械力化学效应

以绿豆淀粉为原料,通过扫描电镜(SEM)、偏光显微镜(PLM)、激光扫描共聚焦显微镜(CLSM)、X-射线衍射(XRD)、差示扫描量热仪(DSC)、快速黏度分析仪(RVA)等手段研究碾轧处理对淀粉结构和性质影响,探究其相互关系并揭示碾轧对绿豆淀粉机械力化学效应。结果表明,碾轧处理3~6 h时,淀粉无定型区和部分结晶区发生破坏,水溶指数、膨胀度、透光率增大,热焓减小。碾轧处理9 h时,淀粉内部发生重结晶,颗粒表面形成球状凸起,脐点区域直链淀粉聚集导致膨胀度、透光率、峰值黏度下降,水溶指数、热焓值、糊化温度增大。碾轧处理12~24 h时,淀粉的结晶区域发生显著破坏,颗粒严重变形,从而使淀粉水溶指数、透光率增大,膨胀度、热焓值减小。根据机械力化学相关理论推断淀粉颗粒内部依次经过了受力阶段、聚集阶段、团聚阶段。     

普鲁兰酶酶解对葛根淀粉理化特性的影响

研究了普鲁兰酶酶解对颗粒态葛根淀粉理化特性的影响。采用快速黏度分析仪（RVA）、差示量热扫描仪（DSC）、偏光显微镜、扫描电子显微镜（SEM）、激光粒度仪、傅里叶红外光谱仪（FTIR）、X射线衍射仪（XRD）对酶解前后葛根淀粉的糊化特性、抗性淀粉含量、热性能、形貌、颗粒大小、结晶结构和分子结构进行了分析。结果表明,酶解后葛根淀粉的峰值黏度和崩解值分别降低了28.33%和94.69%,谷值黏度、最终黏度和回生值分别增加了12.53%、12.47%和12.37%;抗性淀粉含量从1.29%上升至4.60%。酶解后淀粉的偏光十字仍然存在,但颗粒发生膨胀,粒度变大,表层出现剥离;DSC吸热峰向高温区偏移,但吸热焓下降;酶解促进了淀粉分子短程有序结构的生成;葛根淀粉经酶解后,其相对结晶度从37.31%降低至29.10%。     

Physicochemical,crystalline, and thermal properties of native,oxidized, acid,and enzyme hydrolyzed Chinese yam (Dioscorea opposite Thunb) starch

Native yam starch was modified by oxidation (with sodium hypochlorite), acid, and enzyme (with gluco‐amylase), respectively. Ash content, fat content, protein, and AM contents were reduced following modifications. All the modifications reduced swelling capacity whereas improved the solubility. The SEM of the native starch showed the presence of large oval or spherical to small irregular‐shaped granules, however, oxidation and hydrolysis caused collapse of the granules. From the XRD, the typical C‐type XRD pattern of the native starch changed to the typical A‐type XRD pattern of the three modified starches. The above results also demonstrated that amorphous region of yam starch granules was preferentially degraded than crystalline region of granules. DSC showed that oxidation and acid/enzyme hydrolysis reduced peak temperature of gelatinization (T_p) of native starch significantly. Enthalpy of gelatinization (ΔH) of oxidation and enzyme starch was reduced but it has no obviously change following acid modification.     

Physicochemical Properties of Ginkgo Kernal Starch

Native starch was isolated from ginkgo kernels, its physicochemical properties were investigated using some physical methods. Ginkgo starch granules were mostly oval in shape with a central Maltese cross and average long axis of 11 μm. Ginkgo starch contained 29.9% amylose content and exhibited an A-type crystallinity with 27.2% crystalline degree. Ginkgo starch had significantly higher gelatinization conclusion temperature, temperature range, and enthalpy than potato and rice starches. Ginkgo starch showed lower hot viscosity and higher breakdown viscosity than potato and rice starches. Ginkgo starch possessed markedly higher swelling power and resistance to α-amylase and amyloglucosidase hydrolysis than rice starch.