脂类和颗粒结合蛋白对小麦A、B淀粉理化性质的影响

淀粉颗粒中的脂类和颗粒结合蛋白对其理化和结构性质存在一定影响,研究了小麦A、B淀粉经脱脂、脱蛋白处理后其化学组成、颗粒形态、糊特性等性质。结果表明:脱脂处理对小麦A、B淀粉的晶体类型、溶解度、膨胀度、起始温度、峰值温度、终值温度、热焓值、峰值黏度、谷黏度、衰减值、最终黏度、峰值时间、成糊温度均无显著性影响,相对结晶度降低。脱蛋白处理使小麦淀粉溶解度和膨胀度随温度的增长趋势显著增加,相对结晶度、起始温度、峰值温度、终值温度、峰值黏度、衰减值、回生值显著增大,谷黏度和峰值时间显著降低,对晶体类型、热焓值无显著影响。脱蛋白处理对小麦A、B淀粉理化性质的影响显著高于脱脂处理。     

脱脂对三种豆类淀粉理化性质的影响

为研究脂类化合物对豆类淀粉理化性质的影响,以红豆、鹰嘴豆、蚕豆为材料,采用湿法分离淀粉并做脱脂处理,分析了脱脂前后三种豆类淀粉颗粒特性、热特性、淀粉糊特性存在的差别。结果表明：与脱脂前相比,脱脂处理后三种淀粉的偏光十字更加明显,溶解度、膨胀度和透明度升高,热焓值降低,冻融稳定性变差,淀粉晶型、起糊温度、峰值黏度、终值黏度、破损值、回生值和凝沉性无明显变化。脱脂处理使三种豆类淀粉的溶解度、膨胀度、糊透明度得到改善。     

糯玉米粉、淀粉和脱脂淀粉的理化特性研究

以4个糯玉米品种为材料,比较分析了糯玉米粉、淀粉(脱蛋白)和脱脂淀粉(脱蛋白脱脂)的理化特性.结果表现,脱蛋白或脱蛋白脱脂处理不改变材料的结晶类型,各材料均表现为典型的"A"型衍射图谱.理化特性在糯玉米粉、淀粉和脱脂淀粉间存在显著差异.结晶度、膨胀势、回复值、峰值时间和糊化温度以糯玉米粉最高,脱脂淀粉最低;溶解度、峰值黏度和谷值黏度以淀粉最高,米粉最低;透光率以脱脂淀粉最高,米粉最低;但4个糯玉米品种的终值黏度变化趋势不甚明显.     

脱蛋白或脱脂对薏苡淀粉糊化和体外消化特性的影响

以薏苡为材料,制备脱淀粉颗粒相关蛋白(starch granule-associated proteins,SGAPs)、脱脂和脱SGAPs脱脂薏苡淀粉,探究了脱SGAPs和脱脂对薏苡淀粉糊化和体外消化特性的影响。结果表明,脱SGAPs和脱脂提高了薏苡淀粉的膨胀势、溶解度、快消化淀粉和慢消化淀粉,降低了1 045 cm^-1与1 022 cm^-1处峰强度比值、峰值黏度、谷值黏度、崩解值和抗性淀粉。脱SGAPs显著提高了薏苡淀粉的糊化转变温度、糊化焓,显著降低了糊化起始温度。脱SGAPs对淀粉短程有序结构和消化特性的影响大于脱脂,脱脂对薏苡淀粉的热力学性质无显著影响,脱SGAPs和脱脂对淀粉的晶型无显著影响。研究结果对于了解薏苡淀粉特性以及薏苡淀粉在食品加工中的应用具有潜在价值。     

脱脂对3种豆类淀粉理化性质的影响

为研究脂类物质对豆类淀粉理化性质的影响,以红豆、鹰嘴豆、蚕豆为材料,采用湿法分离淀粉并做脱脂处理,分析了脱脂前后3种豆类淀粉颗粒特性、热特性、淀粉糊特性存在的差别。结果表明:脱脂后3种淀粉的溶解度、膨胀度和糊透明度升高,热焓值降低,冻融稳定性变差,颗粒形貌、偏光十字、淀粉晶型、起糊温度、峰值黏度、终值黏度、破损值、回生值和凝沉性无明显变化。脱脂处理使3种豆类淀粉的溶解度、膨胀度、糊透明度得到改善。     

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。     

荞麦淀粉-小麦淀粉混配体系理化特性的研究

为阐明不同种淀粉混配与原淀粉理化特性的差异,以甜荞麦粉和高筋小麦粉及30%荞麦粉-70%小麦粉混粉为原料,采用Osbrone法分离淀粉,分析3种淀粉颗粒组成、颗粒结构、溶解度及膨胀度、淀粉糊特性、热特性等存在的差异。结果表明:与荞麦淀粉和小麦淀粉相比,混配淀粉致密度最差、结晶度最高、晶体崩解所需的能量最大;混配淀粉比单一淀粉更难糊化;热焓值更高;混配淀粉的溶解度和膨胀度在温度较高时升高的最缓慢;颗粒形貌、淀粉晶型无明显变化。     

白芸豆淀粉与小利马豆淀粉理化性质的比较研究

本实验以白芸豆和小利马豆为原料,采用碱法提取淀粉,对白芸豆淀粉和小利马豆淀粉的理化特性进行分析研究。结果表明,白芸豆和小利马豆的淀粉颗粒均呈表面光滑、无棱角及裂痕的特征,且2种淀粉的微晶结构均为A型;2种豆类淀粉的溶解度和膨胀度均随温度的升高而增加。小利马豆淀粉和白芸豆淀粉在冻融稳定性、透明度和成糊特性等方面存在显著差异,小利马豆淀粉的膨胀度、溶解度及淀粉糊的冻融稳定性和透明度更好,而白芸豆淀粉呈现起糊温度、峰值黏度、破损值和回生值较低的成糊特性,易成糊、抗剪切。     

脱脂对糯玉米淀粉热力学特性的影响

以4个糯玉米淀粉为材料,对其进行脱脂处理,分析了其对淀粉热力学特性的影响。结果表明,脱脂使淀粉中的磷元素含量显著降低,导致淀粉的起始温度、峰值温度、终值温度、峰值指数和热焓值降低,糊化范围扩大。淀粉和脱脂淀粉糊化冷藏后发生回生,表现为脱脂增加了回生淀粉的热焓值,进而增加了淀粉的回生值和峰值指数,而起始温度、峰值温度、终值温度和糊化范围受脱脂影响较小。淀粉和脱脂淀粉的热焓值存在显著的基因型差异,淀粉的热焓值以渝糯408最低,脱脂淀粉的热焓值以郑彩糯1号最低。淀粉回生后热焓值和回生值差异较小,而脱脂淀粉回生后热焓值和回生值以YA30142最高,郑彩糯1号最低。     

压热法结合反复冻融制备小麦抗性淀粉及其理化性质研究

以小麦淀粉为原料,利用压热法制备抗性淀粉,再经过反复冻融,以期提高产品的抗性淀粉含量。对产品的颗粒形貌、碘吸收曲线、持水力、膨胀度、溶解度等理化性质进行了测定。结果表明,反复冻融次数为6次时得到的小麦抗性淀粉含量最高,为18.31%,经过反复冻融处理的小麦抗性淀粉,颗粒呈不规则形,且在碘吸收曲线中稍微偏向直链淀粉吸收峰,表明其可能含有较多的直链淀粉。与小麦原淀粉相比,经反复冻融处理的小麦抗性淀粉的持水力与膨胀度显著增加,而溶解度显著降低。     

复合酶法改性糯麦A-、B-型淀粉及对其结构和消化特性的影响

以从糯麦淀粉中分离所得的A-、B-型淀粉为研究对象,并以此作为受体,高直链玉米淀粉为供体,利用普鲁兰酶和分支酶协同处理对糯麦淀粉进行改性,测定其颗粒形态、结晶结构以及表观直链淀粉含量、溶解度、膨胀力等理化性质,并对其消化特性进行考察。结果表明：采用普鲁兰酶和分支酶两种复合酶法改性的糯麦A-、B-型淀粉,其预测血糖指数显著降低,表观直链淀粉含量显著增加、溶解度随着温度的增加而变大,膨胀力随着温度的增加基本保持不变。采用扫描电子显微镜观察到酶法改性后的淀粉颗粒形态出现孔洞结构,利用X射线衍射和傅里叶红外光谱分析相对结晶度和1 047 cm－1/1 022 cm－1处的比值可得,复合酶改性淀粉的长程有序结构和短程有序结构显著改善。通过普鲁兰酶预处理后再用分支酶改性,对糯麦A-型和B-型淀粉进行结构修饰,能够显著改善其消化特性。     

Hydrothermal modifications of tropical tuber starches – Effect of ANN on the physicochemical,rheological and gelatinization characteristics

Cassava, sweet potato and arrowroot starches were hydrothermally modified by ANN under different conditions of temperature, moisture and time duration of treatment and the properties are compared. ANN brought about changes in swelling volume, solubility, gelatinization and rheological properties. The three starches behaved differently after the treatment. All the three tuber starches showed decrease in swelling volume after ANN treatment. The solubility decreased for cassava starch, whereas it slightly increased for majority of annealed sweet potato starches and significantly increased for arrowroot starch. For cassava starch, there was a decrease in peak viscosity, but for the other two starches, it increased after ANN. Differential scanning calorimetric studies showed that ANN resulted in a narrowing of DSC patterns for all the starches. The effect of ANN on the dynamic rheological properties was found to depend up on the source of starch. The modification resulted in increased gel hardness, gumminess, adhesiveness and decreased springiness for the starch gels. Tuber starches became less susceptible to enzyme action after ANN.     

Physicochemical Properties of Canna edulis Ker Starch on Heat-Moisture Treatment

Canna edulis Ker starch was modified by heat-moisture treatment at moisture levels ranging from 18 to 27 g/100 g starch and its physicochemical properties were investigated. Amylose content, swelling power, solubility as well as water and oil absorption capacity in native starch were higher than in all treated starches. However, alkaline water retention and acid susceptibility of native starch were lower, along with different extent of amylose leaching. The result in the X-ray diffraction measurement revealed that the crystalline type of the starch gradually changed from B-type to A-type, and the degree of crystallinity changed. Investigation on thermal properties showed that the gelatinization enthalpy decreased, whereas the onset temperature, peak temperature, concluding temperature and transition temperature range increased in modified starch than in native starch. In addition, all modified starches exhibited remarkably low values of peak viscosity, hot pasting viscosity and final viscosity, compared to those of native starch.     

不同物理方法处理对碎米中淀粉特性的影响

采用挤压、微波、超声波三种物理方法对水分含量18%的碎米淀粉进行处理,研究分析碎米淀粉经物理方法处理前后的理化性质和结构变化。结果表明,碎米淀粉经微波和超声处理后酶解力增加,糊化黏度下降,而溶解度、膨胀力、糊化温度和直链淀粉含量变化不显著;两种淀粉颗粒表面棱角减少,淀粉颗粒晶型基本没有发生变化,淀粉结晶区降低。挤压后的碎米淀粉变化较大,颗粒形状为片状,凝沉性强,1.0 h后体积仅为3 mL,糊化温度明显降低至55.0 ℃,直链淀粉含量增长为30.75%,溶解度强,为0.59%,酶解力达到45%,X-射线主要衍射峰的强度降低。     

Effect of hydroxypropyl β-cyclodextrin on physical properties and transition parameters of amylose–lipid complexes of native and acetylated starches

The effect of hydroxpropyl β-cyclodextrin (HPβ-CD) on physical properties and digestibility of wheat, potato, waxy maize and high-amylose maize starches before and after acetylation was studied. Effect of HPβ-CD on amylose–lipid complexes in native and acetylated potato starches synthesized using α-lysophosphatidylcholine was also studied. Acetylation increased swelling factor, amylose leaching, peak viscosity and susceptibility to α-amylase hydrolysis, but decreased gelatinization temperature and enthalpy and gel hardness in all starches. HPβ-CD markedly increased swelling factor and amylose leaching in native and acetylated wheat starches but had little or no impact on other starches. Wheat starch gelatinization enthalpy decreased in the presence of HPβ-CD but gelatinization temperature of all the starches was slightly increased. HPβ-CD had no influence on enzymatic hydrolysis. Melting enthalpy of amylose–lipid complex in both native and acetylated wheat starches was decreased by HPβ-CD. Acetylation also decreased the melting enthalpy of amylose–lipid complex in wheat starch. Similar trend of thermal transitions was observed in the presence of HPβ-CD for the amylose–lipid complexes synthesized in potato starch. Acetylation reduces the complex formation ability of the amylose polymer. Similar to gelatinization, acetylation widened the melting temperature range of amylose–lipid complexes while shifting it to a lower temperature. Higher swelling and amylose leaching, and decreased gelatinization temperature and enthalpy resulting from acetylation of wheat starch is consistent with its influence on starch hydration. Similar effects resulting from the inclusion of HPβ-CD were consistent with the disruption of amylose–lipid complex by HPβ-CD which promotes granular hydration.     

3种百合淀粉主要理化性质的研究

对湖南株洲和宜章两地的卷丹及麝香百合的淀粉的主要理化性质进行了研究。其结果表明:株洲、宜章卷丹及麝香百合淀粉的淀粉含量分别为78·74%、87·33%、78·36%,其直链淀粉分别为24·36%、26·04%、21·38%;淀粉晶体结构是B型结构;糊化温度分别为51·9~54·3℃、55·7~61·0℃、57·3~60·7℃。随着加热温度的上升,百合淀粉的膨胀度和溶解度均呈增加趋势,在65℃时膨胀较小,在75~95℃时膨胀较快,为典型的二段膨胀过程,属限制型膨胀淀粉。     

Pasting,Thermal, Hydration,and Functional Properties of Annealed and Heat-Moisture Treated Starch of Sword Bean (Canavalia gladiata)

The effects of annealing (ANN) and heat-moisture treatments (HMT) on the physicochemical and functional properties of Sword bean starches were investigated. The pasting properties differ significantly among the starches, with peak viscosity ranging from 399.17 RVU to 438.33 RVU; however, all the starches exhibited ‘Type C’ class with restricted swelling. The HMT starches had the highest gelatinization temperature, while change in enthalpy of gelatinization, ΔH_gel of the native starch, was higher (13.82 J/g) than that of the modified starches (1.39–6.74 J/g). The solubility and swelling power of all the starches increased as the temperature increased. The oil and water absorption capacity of the starches ranges between 3.24–3.91 g/g and 2.42–3.35 g/g, respectively. HMT (at 25 and 30% moisture level) changes the X-ray diffraction pattern of the starch from Type ‘B’ to Type ‘C’. The Scanning electron micrograph results revealed the starch granules with smooth ellipsoids and indentation in their centre, hydrothermal modification showed little effect on the morphology and size of the granules. Hydrothermal modification improved the physicochemical and functional properties of the starch without destroying the granule of the starch.     

湿热处理对不同晶型淀粉理化性质及消化性的影响

采用三种不同晶型淀粉即玉米淀粉(A型)、马铃薯淀粉(B型)、豌豆淀粉(C型)为原料,在水分含量为25%、温度120℃条件下湿热处理13 h,研究湿热处理对不同晶型淀粉的理化性质及消化性的影响。研究表明,与原淀粉相比,经湿热处理的三种淀粉的结晶结构均发生了改变,玉米淀粉由A型变为了A+V型,马铃薯淀粉和豌豆淀粉分别由B型和C型变为了A型;三种淀粉颗粒表面均出现了不同程度的破损;三种淀粉的部分颗粒的偏光十字的中心强度有所减弱;三种淀粉样品的糊化温度均升高,但A型和B型淀粉的焓值降低,而C型淀粉的焓值升高;三种淀粉的抗性组分含量均有所升高,抗消化性显著增强,其中C型淀粉变化最明显。     

Effect of heat-moisture treatment on rice starch of varying amylose content

The effect of heat-moisture treatment (HMT) on the properties of rice starches with high-, medium- and low-amylose content was investigated. The starches were adjusted to 15%, 20% and 25% moisture levels, and heated at 110 °C for 1 h. The swelling power, solubility, pasting properties, morphology, enzymatic susceptibility and X-ray crystallinity of the starches were evaluated. HMT reduced the swelling power and solubility of the starches. The strongest effect of HMT occurred on the high-amylose starch; the pasting temperature was increased and the peak viscosity, breakdown, final viscosity and the setback were reduced. HMT increased the starch’s susceptibility to α-amylase and promoted a reduction in the starch relative crystallinity.