3种甘薯淀粉性质差异分析

以白心薯、红心薯和紫心薯为原料,测定了3种不同甘薯淀粉糊的透明度、凝沉性、冻融稳定性、表观黏度、膨润度和溶解度等物理特性,并进行差异分析。试验结果表明,白心薯淀粉糊的直链淀粉含量最高,溶解度和膨润度较小,透明度最低,凝沉性最高,冻融稳定性最强,表观黏度最大,热稳定性差;紫心薯淀粉糊的溶解度和膨润度在各温度下都比其它两种甘薯淀粉糊高,属于高膨胀型淀粉,表明紫心薯淀粉与水分子结合能力最强,紫心薯淀粉糊的热稳定性和凝胶强度好,透明度最高,凝沉性最低,表观黏度最小;而红心薯淀粉糊的各种物理特性均居于白心薯和紫心薯两种淀粉糊之间。     

酶辅助碱法提取龙眼核淀粉的结构与理化性质研究

目的:明确酶辅助碱法提取的龙眼核淀粉的结构及理化性质。方法:以龙眼核为原料,碱性蛋白酶为酶解剂提取龙眼核淀粉,研究了其化学组成、粒径、微观形貌、晶体结构、透明度、溶解度及膨润力、热力学特性及糊化特性等。结果:100 g龙眼核淀粉中含有82.64 g淀粉、0.68 g粗脂肪、0.46 g粗蛋白和1.06 g灰分,其直链淀粉含量为36.37%;其颗粒多呈椭圆形或不规则多边形,平均粒径为11.21 μm,结晶结构为A型,近程有序程度较高;1%（w/v）龙眼核淀粉糊的透光率为4%;溶解度和膨润力均随温度上升而增大,90 ℃时分别为11.26%和15.93%;龙眼核淀粉具有较高的糊化起始温度（70.4 ℃）、峰值温度（75.9 ℃）、结束温度（82.1 ℃）和糊化焓（13.7 J/g）,其热糊稳定性较差,冷糊稳定性较好。结论:酶辅助碱法提取的龙眼核淀粉直链淀粉含量高,蛋白质含量下降明显,颗粒小,不易糊化。     

板栗淀粉糊的特性研究

通过对板栗粉中占主要成分的淀粉的研究,为后期板栗粉冲剂开发提供试验理论依据,探讨了板栗淀粉糊的溶解度和膨润力、透明度、凝沉性、冻融稳定性以及凝胶强度等性质,并与小麦淀粉、玉米淀粉进行了比较。研究结果表明,从85℃开始,板粟淀粉的溶解度和膨润力都有很明显的上升;板栗淀粉的透明度低于小麦淀粉和玉米淀粉相似;凝沉现象随时间的增加比较明显;板栗淀粉的冻融稳定性和凝胶强度性质较其他两种淀粉出色。     

马铃薯淀粉的物化性质研究

研究马铃薯淀粉的组成、颗粒形貌、粒径大小及溶解度与膨润力、透明度、凝沉性、糊化方面的性质,并与绿豆、玉米淀粉进行比较.结果表明,马铃薯淀粉的蛋白质含量为0.27%, 直链淀粉含量为20.4%,颗粒为椭圆形,平均粒径为40 μm;马铃薯淀粉的溶解度与膨润力较高;马铃薯淀粉的透明度为66.8%,凝沉性高于豆类淀粉,峰值黏度为2 000 BU.     

乙酰化二淀粉磷酸酯性质的研究

本文研究了交联一酯化复合变性淀粉——乙酰化二淀粉磷酸酯的结构和物理化学特性。结果表明:由于乙酰基取代了淀粉分子的部分羟基而使淀粉与碘的结合能力下降,展现为直链淀粉含量降低,淀粉的溶解度和膨润力增加;淀粉糊的透明度和冻融稳定性有所改善,交联反应还提高了淀粉的耐热、耐酸稳定性。     

小麦交联淀粉的制备及性质的研究

以小麦淀粉为原料，环氧氯丙烷为交联剂，制备小麦交联淀粉。并对小麦交联淀粉的冻融稳定性、透明度、溶解度和膨润力、抗老化性、抗剪切力、抗酸性等性质进行研究。结果表明：用环氧氯丙烷交联后的小麦淀粉具有良好的冻融稳定性、抗老化性、抗剪切力、抗酸性和一定的透明度、溶解度和膨润力。     

微山湖野生白莲子淀粉的性质研究

淀粉是莲子的主要成分,其结构和性质直接关系到莲子的加工和应用.本实验研究了微山湖野生白莲子淀粉的直链淀粉含量、透明度、溶解度、膨润力和冻融稳定性等特性,以及淀粉浓度、温度、糊化时间、剪切速率等对淀粉糊黏度的影响,为开发莲子深加工产品提供理论基础.     

燕麦淀粉与常见淀粉的性质对比研究

以常见市售淀粉(小麦淀粉、玉米淀粉、土豆淀粉)为参比,研究了燕麦淀粉的透明度、凝沉性、冻融稳定性、溶解度、膨润力和糊化特性.结果表明:燕麦淀粉的透明度、凝沉性、冻融稳定性比小麦淀粉、玉米淀粉和土豆淀粉都要差.燕麦淀粉的溶解度在4种淀粉中是最高的,而膨润力是最低的.燕麦淀粉的糊化特性与小麦淀粉较接近.     

退火处理对葛根淀粉理化性质的影响

将配制的一定浓度的葛根淀粉乳退火处理不同的时间,得到不同退火时间样品。分析退火处理前后淀粉的表观直链淀粉含量、膨润力、溶解度、颗粒形貌、冻融稳定性和结晶结构等理化特性。结果显示,退火处理使葛根淀粉膨润力和溶解度降低,但峰值黏度和糊化温度升高,退火处理提高了葛根淀粉糊的冻融稳定性;然而退火处理并没有改变葛根淀粉的颗粒形貌与结晶结构,仅是提高了葛根淀粉的相对结晶度。     

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。     

芡实粉和芡实淀粉理化性质和消化性研究

以芡实为原料制取芡实粉和芡实淀粉样品,研究了其糊化性、溶胀度、可溶指数、质构性和消化性等性质.结果表明,芡实淀粉样品的黏度明显高于芡实粉样品,芡实粉的峰值黏度与芡实淀粉相比降低了57.75％;随温度升高,芡实粉和芡实淀粉的溶胀度和可溶指数呈现递增趋势,但在较高温度下,芡实粉样品的溶胀度和可溶指数明显高于芡实淀粉样品;与芡实淀粉样品相比,芡实粉的凝胶的硬度减少了91.86％;芡实淀粉样品的快速消化淀粉含量明显高于芡实粉样品,但慢速消化淀粉的含量要低于芡实粉样品,抗性淀粉的含量高于芡实淀粉样品.     

Milling of rice grains: The roles of starch structures in the solubility and swelling properties of rice flour

Rice flours with different particle sizes and degrees of damaged starch granules were produced by hammer milling and cryogenic milling of rice grains, where degradation of starch molecules was evident in the hammer‐milled flours, but not in the cryogenically milled flours. The solubility and swelling properties of the resulting rice flours were determined in cold (30°C) and hot water (90°C). The cold‐ and hot‐water starch solubility was strongly correlated with the degree of damaged starch granules, and weakly with the particle size of rice flour. No evident correlations were observed between starch solubility and the molecular structures, indicating that molecular degradation by milling process was not the only precondition of increased starch solubility. Possible mechanism for the observed correlations is that increasing surface area and/or exposure of loosely packed inner part of starch granules with increasing degree of damaged starch granules allowed more starch molecules to leach out in cold and hot water. Furthermore, the cold‐water swelling of rice flour was strongly correlated with the degree of damaged starch granules, possibly due to the rapid hydration of damaged starch granules, whereas the hot‐water swelling did not show any correlations with flour particle size and granular and molecular starch structures. The results have provided better insights in the relationship between starch structures and solubility and swelling properties of rice flour, which can be used to improve the manufacture and selection criteria of rice flour for better products.     

Physicochemical and functional properties of Caryota urens flour as compared to wheat flour

Starch digestibility, thermal, pasting and gelling properties of Caryota urens (CU) flour were investigated using wheat flour as reference. Amylose content of CU and wheat flour was 32.1% and 28.3%, respectively. CU flour had very low content of protein and lipid but had a high content of total starch (98.2%) and resistant starch (RS) [42.5%]. Gelatinisation temperature (78.5 °C) of CU flour was higher than wheat flour. Pasting behaviour of CU flour was similar to that of high swelling tuber and root and waxy starches. CU flour retrograded to a greater extent than wheat flour. Very specific gelling behaviour was noticed for CU flour where it produced significantly harder gel with high paste clarity, fracture ability, adhesiveness, gumminess and chewiness. Expected glycaemic index (eGI) of CU and wheat flour was 92.4 and 100.4, respectively. CU flour had high eGI despite high content of resistant starch.     

Comparisons of physicochemical properties and antioxidant activities among pumpkin (Cucurbita moschata L.) flour and isolated starches from fresh pumpkin or flour

Physicochemical properties (pasting and thermal properties, swelling power, water solubility and antioxidant activities) and chemical composition of pumpkin flour (PF) and starches, isolated from fresh pumpkin (SFF) or flour (SFP) were compared. SFP and SFF had similar proximate composition and amylose content. Drying process during PF preparation modified starch properties. PF exhibited greater antioxidant activities (DPPH, ABTS and FRAP), but had lower β‐carotene than fresh pumpkin. SFF and SFP had higher amylose content than PF, and exhibited a B‐type X‐ray diffraction pattern with spherical and dome‐like starch granules. Peak viscosity of SFP was relatively higher than that of SFF, probably due to lower swelling power and water solubility, which indicated increased granular rigidity in the SFP starch structure. Compared with SFF and SFP, PF had significantly higher onset (T_o), peak (T_p) and conclusion (T_c) temperatures due to a lower starch content and relatively higher fibre content, which resulted in lower gelatinisation enthalpy (ΔH).     

面条品质与小麦粉品质特性关系的探讨

选用品质不同的小麦粉33份制作面条,探讨小麦粉品质性状和面条煮面品质的关系。结果表明,面条品质是小麦粉多种品质性状综合作用的结果,不同小麦粉品质性状对面条外观和质地作用的方向和程度不同,蛋白质质量(面筋强度和延伸性)和淀粉糊化特性对面条品质的影响较大,蛋白质质量对面条质地有较大的正向影响,对面条外观有一定的负向影响,淀粉糊化特性对面条外观和质地均有显著正向作用,而蛋白质数量对面条适口性和韧性也有一定正向作用。面筋强度较高、淀粉特性好的小麦粉适宜制作优质面条。     

白糯小麦粉与糯米粉物化特性的比较

本试验研究了白糯小麦粉与普通小麦粉、糯米粉物化性质的差异,测定了白糯小麦粉、普通小麦粉和糯米粉的膨胀性、黏度特性、持水能力、糊透明度、冻融稳定性、消化性和糊化回生特性。结果表明,随温度的升高,白糯小麦粉、普通小麦粉和糯米粉的膨胀度随温度的升高呈递增趋势,但在较高温度下,白糯小麦粉的膨胀度高于糯米粉;与普通小麦粉比,白糯小麦粉有较高的峰值黏度、崩解值和较低的谷黏度、终黏度、回生值,糊化时间短,糊化温度低,不易消化;与糯米粉相比,白糯小麦粉的水合能力低,糊透明度差,峰值黏度、谷黏度、崩解值、终黏度和回生值低,糊化时间短,糊化温度高,易消化。白糯小麦粉的冻融稳定性好、抗回生能力强。     

挤压加工对苦荞粉理化性质的影响

为了阐明挤压加工技术对苦荞粉理化性质的影响,分别研究了不同挤压温度、物料水分和螺杆转速对挤压苦荞粉的吸水性指数、水溶性指数、膨胀势、糊化及凝胶特性的影响规律。结果表明:与未挤压苦荞粉相比,经挤压改性后的苦荞粉在30℃水浴时有更好的吸水性和水溶性;在100℃水浴时的水溶性增大,吸水性减小;膨胀势、糊化特征值及凝胶特征值均明显升高。随挤压温度升高,挤压苦荞粉的峰值粘度、衰减值增大,谷值粘度、回生值降低,制成的凝胶品质更好;随物料水分升高,吸水性指数、膨胀势、各糊化特征值显著增大,水溶性指数明显降低,低物料水分形成的凝胶品质较好;随螺杆转速升高,水溶性指数增大,吸水性指数和峰值粘度、谷值粘度、衰减值稍降低,膨胀势先增大后减小,转速越高的苦荞粉的凝胶品质越好。综合而言,物料水分变化对挤压苦荞粉的各理化性质影响最大。吸水性指数和水溶性指数与糊化特性、凝胶特性都有显著相关性(P0.05);膨胀势与糊化特性极显著正相关(P0.01),与凝胶特性没有显著相关性。     

Effect of wheat flour characteristics on sponge cake quality

BACKGROUND: To select the flour parameters that relate strongly to cake‐making performance, in this study the relationship between sponge cake quality, solvent retention capacity (SRC) profile and flour physicochemical characteristics was investigated using 38 soft wheat samples of different origins. Particle size average, protein, damaged starch, water‐soluble pentosans, total pentosans, SRC and pasting properties were analysed. Sponge cake volume and crumb texture were measured to evaluate cake quality. Cluster analysis was applied to assess differences in flour quality parameters among wheat lines based on the SRC profile. RESULTS: Cluster 1 showed significantly higher sponge cake volume and crumb softness, finer particle size and lower SRC sucrose, SRC carbonate, SRC water, damaged starch and protein content. Particle size, damaged starch, protein, thickening capacity and SRC parameters correlated negatively with sponge cake volume, while total pentosans and pasting temperature showed the opposite effect. CONCLUSION: The negative correlations between cake volume and SRC parameters along with the cluster analysis results indicated that flours with smaller particle size, lower absorption capacity and higher pasting temperature had better cake‐making performance. Some simple analyses, such as SRC, particle size distribution and pasting properties, may help to choose flours suitable for cake making. © 2012 Society of Chemical Industry     

蕉藕淀粉与薯类淀粉特性对比研究

为探索蕉藕淀粉应用范围,选取木薯淀粉、马铃薯淀粉、红薯淀粉等薯类淀粉为对照,对蕉藕淀粉与常见薯类淀粉的组成、吸水(油)率、溶解度、膨胀度、透明度、凝沉性、凝胶强度、冻融稳定性及黏度等特性进行了对比分析。结果显示:蕉藕淀粉与常见薯类淀粉特性相比除吸水性差异不显著外,吸油率、溶解度、膨胀度、透明度、凝沉性、凝胶强度、冻融稳定性及黏度变化均存在显著差异,可利用蕉藕淀粉直链淀粉含量高、透明度好、凝胶强度高等特性,开发新型淀粉食品和增稠稳定剂。     

小麦粉中蛋白质和淀粉含量对面条品质的影响

对小麦粉中的蛋白质和淀粉组分进行了分离,将淀粉含量不同的混合粉制作成面条,分析其质构特性和食用品质。将面条煮制后,对熟面条进行了质构分析,测定了熟面条的硬拉伸性能、剪切性能和蒸煮损失,并进行了感官品质评价。研究结果表明:随着小麦粉中的淀粉含量的增加(蛋白质含量的降低),面条的质构特性、拉伸性能、剪切性能都呈现显著下降的变化趋势(P<0.05),而面条的蒸煮损失显著增加(P<0.05)。此外,面条的感官评价与质构分析的结果相一致。