非晶颗粒态西米淀粉的理化性质研究

利用乙醇溶剂法制备非晶颗粒态西米淀粉,并对其理化性质进行研究。研究表明:非晶颗粒态西米淀粉具有特殊的偏光性质,中心具有同心圆形的亮环;在乙醇溶剂中进行西米淀粉颗粒的非晶化转化过程中,原有的结晶结构完全破坏,西米淀粉形成了新的结晶结构,X-衍射图谱在13、21°有2个新的衍射峰,结晶类型也由原来的A型转变为V型;由于新晶体的形成,非晶颗粒态西米淀粉的耐高温能力提高,糊的透明度由29.1%下降到4.7%。     

西米交联淀粉的理化性质

以三偏磷酸钠为交联剂,采用水分散法制备西米交联淀粉,利用扫描电镜、聚焦光束发射测量仪、Bra-bender快速黏度计和紫外分光光度计对其性质进行测定和分析,并与西米原淀粉进行比较。结果表明:西米交联淀粉发生了中等程度的交联;西米交联淀粉保持了西米原淀粉绝大多数颗粒完整、呈椭圆形、存在断切面和断切面处有凹坑的形貌特征,但其表面比较粗糙,有凹痕,且断切面处凹坑更加明显;西米交联淀粉颗粒粒径分布图呈单峰,在水相中的平均粒径为30.1μm,比西米原淀粉颗粒小;西米交联淀粉比西米原淀粉难于糊化,其热稳定性和冷糊稳定性均优于西米原淀粉,有很高的最终黏度;西米交联淀粉的透光率为5.1%,小于西米原淀粉,其透明度较差。     

青稞淀粉和小麦淀粉的理化性质比较研究

研究了青稞淀粉的理化性质,包括淀粉的颗粒形态、粒度分布及淀粉糊透明度、溶解度、膨胀力和糊化特性,并与小麦淀粉性质进行比较。结果表明:青稞淀粉颗粒的平均粒径大于小麦淀粉颗粒的平均粒径,青稞淀粉颗粒大小和形状分布均匀;青稞淀粉糊透明度大于小麦淀粉糊,但在储藏过程中,青稞淀粉糊透光率变化显著;青稞淀粉的溶解度和膨胀力均大于小麦淀粉糊,这与小麦淀粉中小颗粒淀粉含量较多有关;与小麦淀粉的糊化相比,青稞淀粉成糊温度低,糊化容易,但峰值黏度低,衰减值大,热糊稳定性差,回生值大,冷糊稳定性差,易老化。     

西米羟丙基淀粉的理化性质研究

利用环氧丙烷为醚化剂制备西米羟丙基淀粉,并对其理化性质进行研究。结果表明:醚化后淀粉的颗粒形貌没有发生变化;糊化起始温度(T_o),峰值温度(T_p),终止温度(T_c)以及热焓值(ΔH)均高于原西米淀粉;透明度提高,远高于西米原淀粉;凝沉性增强,冷糊和热糊稳定性提高,表观黏度降低,流动性增加。     

糯小麦淀粉品质特性研究

以糯小麦5017为材料,小偃6号作对照,对糯小麦A、B淀粉的直链淀粉含量及其他淀粉品质特性进行了研究.结果表明,糯小麦淀粉颗粒呈现明显的偏光十字,且A淀粉粒大于B淀粉粒;糯小麦A、B淀粉直链淀粉含量极低,分别为2.81%、0.30%,其直链淀粉含量的大幅度降低导致膨胀特性发生了改变;糯小麦淀粉糊对热不稳定,且不易形成凝胶,老化速度慢,糊透明度不高,但冻融稳定性较好.     

西米柠檬酸酯淀粉颗粒结构与性质研究

利用光学显微镜、扫描电子显微镜、紫外分光光度计和布拉班德黏度计对西米柠檬酸酯淀粉的性质进行测定和分析,并与西米原淀粉进行比较。结果表明:西米淀粉经柠檬酸酯化作用后,其表面被侵蚀,甚至有的颗粒已破碎,偏光十字变弱,结晶度降低;西米柠檬酸酯淀粉的溶胀度和透明度都远远小于原淀粉;通过淀粉糊黏度分析发现,西米淀粉与柠檬酸在酯化作用下发生交联,其浆液在黏度测定过程中不发生糊化和胶凝。     

氯化钠对5种不同植物来源淀粉糊特性的影响

以马铃薯淀粉、红薯淀粉、玉米淀粉、绿豆淀粉和小麦淀粉为研究对象,探究氯化钠对淀粉糊特性的影响。结果表明:小麦淀粉的糊化温度最高,添加2%氯化钠后,各淀粉糊化温度均有所提高,峰值黏度出现的时间延后,薯类淀粉和玉米淀粉的崩解值和回升值下降,糊化过程中淀粉颗粒的粒径减小;淀粉的凝沉性、溶解度和膨胀度增大,冻融稳定性得到改善;马铃薯淀粉的透明度较大,除了玉米淀粉,其余淀粉糊的透明度呈下降趋势;在凝胶特性方面,氯化钠能够降低各淀粉的凝胶强度,增大薯类淀粉凝胶的黏度。     

豌豆淀粉与马铃薯淀粉、玉米淀粉理化性质比较

通过对豌豆淀粉、马铃薯淀粉和玉米淀粉的基本组成、颗粒形态、凝沉性、糊化特性、透明度及抗性淀粉含量的测定与比较表明:豌豆淀粉中直链淀粉和蛋白质的含量较高,但其颗粒直径小于马铃薯淀粉;与马铃薯淀粉和玉米淀粉相比,豌豆淀粉易于回生,但糊稳定性较好;豌豆淀粉糊的透明度低于马铃薯淀粉,但其淀粉组成中慢消化淀粉含量高于马铃薯淀粉和玉米淀粉。     

西米醋酸酯淀粉物化性质研究

利用扫描电子显微镜、聚焦光束反射测量仪,红外光谱仪和布拉班德粘度计对西米醋酸酯淀粉性质进行测定和分析,并与马铃薯醋酸酯淀粉进行比较。结果表明:马铃薯淀粉较西米淀粉更易引入乙酰基,乙酰化后淀粉颗粒形状未发生大的改变,西米原淀粉粒度分布为单峰,而马铃薯原淀粉粒度分布为双峰,前者平均粒径大于后者,乙酰化后西米淀粉和马铃薯淀粉粒径均增大;经醋酸酐酯化后西米淀粉和马铃薯淀粉起糊温度、峰值温度及峰值粘度均降低,热稳定性增加,凝沉性变弱。     

食用醋酸酯甘薯淀粉性质的研究

以甘薯淀粉为原料,醋酸酐为酯化剂,以乙酰基含量和取代度为指标,制备出不同取代度系列醋酸酯甘薯淀粉。研究了不同乙酰基含量醋酸酯甘薯淀粉的性质,包括颗粒形态、膨胀度、溶解度、淀粉糊黏度、透明度、凝沉性和冻融稳定性等,为其在食品中的应用提供依据。实验结果表明,随着醋酸酯淀粉取代度的增加,淀粉糊的峰值黏度不断提高,起糊温度不断降低。乙酰化作用提高了淀粉的膨胀度和溶解度以及淀粉糊的透明度和冻融稳定性;降低了淀粉糊的凝沉性。     

西米淀粉颗粒结构与性质的研究

利用光学显微镜、扫描电子显微镜、X-射线衍射仪、聚焦光束发射测量仪、差式量热扫描仪和紫外分光光度计对西米淀粉的性质进行测定和分析,并与马铃薯淀粉和木薯淀粉进行比较。结果表明:西米淀粉颗粒为椭球体,颗粒表面光滑;偏光十字明显;颗粒在水相中的平均粒径为27.3μm;晶体结构为C型,结晶度为25%;DSC测得To、Tp、Tc分别为68.51、72.79、82.29℃,ΔH为12.00J/g;透明度较好。     

Effect of Sago Starch Addition and Steaming Time on Making Cassava Cracker (Keropok)

This work was aimed at investigating the effects of steaming time and different fractions of sago starch (0, 6, 12, 18 and 24%) in mixtures with cassava starch on the properties of crackers as compared to cassava crackers. In the hydrothermal process, the steaming period was varied from 25 to 120 min. The properties of raw starches, half‐finished crackers (HFC) and puffed crackers (PC) were determined. Raw cassava starch had lower amylose content, smaller granule size, lower gelatinization and lower swelling power than sago starch. The properties of the raw starch mixtures varied according to the mixing proportions. Both sago starch content and steaming time influenced cracker quality, especially its expansion, which was related to the degree of gelatinization (DG). Increasing sago starch content caused decreased DG of HFC and hence decreased cracker expansion. Two groups of HFC were obtained; low DG (55–65%, 25‐45 min steaming time) and high DG (>80%, 60‐120 min steaming time) HFC. Generally the expansion increased as the DG increased – however, a too long steaming period (> 75 min) again reduced expansion, apparently the thinner starch gel allowed collapse of the air cells. No treatment gave complete gelatinization; which could be due to insufficient water for starch to gelatinize.     

西米辛烯基琥珀酸淀粉酯的结构表征及性质研究

采用现代仪器分析方法对西米辛烯基琥珀酸淀粉酯的结构特征、颗粒形貌、粒径分布、乳化性、糊粘度等性质进行了测定和研究,并以西米原淀粉作为参照。结果表明,西米淀粉经辛烯基琥珀酸酐处理后,产品的红外光谱在1570cm-1和1714cm-1处出现新的吸收峰,608cm-1处吸收峰加强;颗粒表面受到损害,形状发生不规则变化;颗粒粒径分布不均,平均粒径大于西米原淀粉;乳化能力和乳化稳定性有显著提高;糊粘度明显增大,热糊稳定性高,凝沉性较弱。为进一步研究西米辛烯基琥珀酸淀粉酯的开发应用提供了一定理论依据。     

Effect of debranching and storage condition on crystallinity and functional properties of cassava and potato starches

Debranching starch by pullulanase is considered to improve the RS content of starch which is widely used to produce the starch‐based foods with high‐health benefit impacts. In this study, the cassava and potato starches were debranched by pullulanase, followed by an autoclave treatment and storage at −18°C, 4°C, or 25°C to investigate their crystallinity and functional properties. After debranching, the potato starch contained significantly higher CL (35.4 glucose units) than did the cassava starch (32.4 glucose units). The debranched cassava and potato starches after retrogradation at the storage temperatures had a typical B‐type crystalline structure although the native cassava and potato starches exhibited the different crystalline forms (A‐ and B‐type, respectively). The RS contents of the debranched cassava and potato starches significantly improved with higher RS content of the debranched potato starch than that of the debranched cassava starch at the same storage condition. The storage temperature significantly affected the RS formation of the debranched starches with the highest RS content at storage temperature of −18°C (35 and 48% for the debranched cassava and potato starches, respectively). The debranched starches had significantly lower viscosities and paste clarities but higher solubilities than did the native starches. As a result, the debranched cassava and potato starches can be considered for use not only in functional foods with enhanced health benefits but also in pharmaceutical and cosmetic industries.     

赤小豆淀粉性质的研究

本文研究测定了赤小豆淀粉的各种结构特性,发现淀粉颗粒粒径范围为18～80μm,平均粒径为40.8μm;偏光十字明显,其X-光衍射图样属A型晶体结构,结晶度为40.5%。淀粉碘复合物可见光吸收光谱的最大吸收波长为618nm,链淀粉含量33.2%。赤小豆淀粉在水中的溶胀能力较玉米淀粉大,比木薯淀粉小。赤小豆淀粉糊属于假塑性流体,糊抗剪切能力和凝沉能力均比玉米淀粉、木薯淀粉强,其冷、热糊粘度稳定性较好,单甘酯对赤小豆淀粉糊的影响较为特别。     

Characteristics of raw starch degrading α‐amylase from Bacillus aquimaris MKSC 6.2 associated with soft coral Sinularia sp.

Partially purified α‐amylase from Bacillus aquimaris MKSC 6.2, a bacterium isolated from a soft coral Sinularia sp., Merak Kecil Island, West Java, Indonesia, showed an ability to degrade raw corn, rice, sago, cassava, and potato starches with adsorption percentage in the range of 65–93%. Corn has the highest degree of hydrolysis followed by cassaca, sago potato and rice, consecutively. The end products of starch hydrolysis were a mixture of maltose, maltotriose, maltotetraose, maltopentaose, maltohexaose, and small amount of glucose.     

西米淀粉结构及消化特性

以马铃薯淀粉和红薯淀粉作为参照,用Englyst法测定西米淀粉的消化特性,并研究其成糊特性、直链淀粉含量、分子链长分布以及脂肪含量与消化特性的关系。结果表明：与马铃薯淀粉和红薯淀粉相比,西米淀粉具有较高含量的快消化淀粉（90.32%）和较低的抗消化淀粉含量（3.27%）。西米淀粉样品较低的脂肪含量（0.11%）、较高的短链含量（聚合度10～30,83.57%）、较低的长链含量（聚合度＞55,0.80%）,较高的直链淀粉含量（29.3%）和较低的终值黏度（1 096.67 mPa·s）。对消化特性起主要影响作用的因素有链长分布、直链淀粉含量和脂肪含量。     

紫薯淀粉结构与理化性质研究

目的 了解紫薯淀粉的结构和理化性质。方法 利用碱提取法从紫薯中提取淀粉, 与普通玉米淀粉进行对比, 分别对淀粉结构(分子链结构、结晶结构等)和理化性质(透明度、凝沉性、冻融稳定性、热稳定性)进行研究。结果 紫薯淀粉直链含量(24.5%)比玉米淀粉(26.7%)低, 两者均为A型结晶结构, 但紫薯淀粉的结晶度和分子有序程度比玉米淀粉高; 紫薯淀粉糊的透明度高于玉米淀粉糊, 且随时间延长其透明度下降程度比玉米淀粉糊低; 紫薯淀粉糊不易发生凝沉现象, 但其析水率(21.4%)比玉米淀粉糊高, 即冻融稳定性弱于玉米淀粉糊; 此外, 紫薯淀粉部分结构的热稳定性大于玉米淀粉。结论 紫薯淀粉在分子链结构和结晶结构上与玉米淀粉有较小差异, 但在理化性质上与玉米淀粉差别较大, 可为其工业应用提供指导基础。