绿豆淀粉和芸豆淀粉理化性质比较研究

对绿豆淀粉和芸豆淀粉的颗粒形态及大小、溶解度、膨润力、透光率、糊化特性、老化特性等理化性质差异进行比较。结果表明：芸豆淀粉颗粒多呈椭圆形,粒径大小范围是17.89～28.80μm;绿豆淀粉颗粒呈现圆形或椭圆,形粒径大小范围是10.50～27.59μm;绿豆淀粉的膨润力、溶解度开始上升的温度较芸豆淀粉的早,并且芸豆淀粉的膨润力和溶解度在任意相同温度下都略小于绿豆淀粉;芸豆淀粉比绿豆淀粉的透明度先增加又随后降低,并且绿豆淀粉的透明度变化比较缓慢,而芸豆淀粉的透明度变化非常明显;绿豆淀粉比芸豆淀粉易于糊化;芸豆淀粉老化的速度高于绿豆淀粉。     

颗粒态绿豆抗性淀粉的制备及性质研究

以绿豆淀粉为原料,采用湿热处理制备颗粒态抗性淀粉,并研究其颗粒形貌、直链淀粉含量、溶胀度、黏度及结晶性质等。试验表明:淀粉经过湿热处理后,抗性淀粉含量显著提高;湿热处理淀粉仍保持完整的颗粒外观,属于颗粒态抗性淀粉,部分淀粉颗粒表面出现了裂纹和凹坑,偏光十字强度有所减弱;湿热处理淀粉的直链淀粉含量明显增加,而溶解度、膨胀度和峰值黏度下降,淀粉糊化变得困难;X-射线衍射图谱表明原淀粉和湿热处理淀粉都为"A"型结晶,且湿热处理淀粉在15.2°、17.4°、22.9°左右的衍射峰强度有所加强。     

芸豆淀粉理化特性研究

淀粉是芸豆中的主要碳水化合物,其性质直接影响芸豆资源的开发与利用.以花芸豆、小红芸豆、红芸豆、小黑芸豆和小白芸豆等菜豆属芸豆为试验材料,采用湿磨法提取淀粉,以马铃薯淀粉和玉米淀粉为对照,分析芸豆淀粉的颗粒特性与糊化特性.结果表明,5种芸豆淀粉颗粒形貌相似,大淀粉颗粒多为卵圆形或肾形,小颗粒多呈圆形,淀粉颗粒长轴粒径介于玉米淀粉和马铃薯淀粉之间.淀粉颗粒偏光十字多为较粗的“X”形或斜“十”形,较明显.芸豆淀粉溶解度和膨胀度均随温度升高而增大,属限制型膨胀淀粉.芸豆淀粉的透光度明显小于马铃薯淀粉,冻融稳定性不及玉米淀粉和马铃薯淀粉.芸豆淀粉起糊温度、峰值黏度、破损值、最终黏度和回生值分别为76.6 ～ 77.8℃、117.3 ～ 150.9 RVU、5.0 ～ 32.0 RVU、205.1 ～225.2 RVU和91.9～104.2 RVU.芸豆淀粉糊表现出好的热稳定性、抗剪切,易回生.     

发酵与发芽处理对绿豆淀粉黏度性质的影响

将绿豆进行发酵及发芽处理,研究不同处理对绿豆淀粉黏度的影响。采用快速黏度分析仪（RVA）测定了不同处理的绿豆淀粉糊化特性。结果表明自然发酵对绿豆淀粉黏度影响不大,只有峰值黏度略有下降：生物混合发酵可使样品的峰值黏度和热浆黏度均出现较大幅度的下降,最终黏度下降。绿豆发芽后提取的淀粉其黏度变化较大,其峰黏度上升1248．00mPa·s,热浆黏度上升698．00mPa·s,淀粉的黏度显著上升。     

不同品种绿豆淀粉的功能特性比较研究

以9个品种绿豆淀粉为研究对象,研究了绿豆淀粉的化学组成及糊化特性、溶解度、膨胀度和冻融稳定性等功能特性,并分析了直链淀粉含量与功能特性的相关性。结果表明,不同品种绿豆淀粉直链淀粉含量不同,其分布范围为33.10%~44.08%;不同品种淀粉糊化特性参数间有明显差异;潍绿4号和中绿1号绿豆淀粉峰值粘度显著高于其他品种(p0.05),安绿8号具有最低破损值(p0.05),毛绿豆和安绿092具有较低的回生值。绿豆淀粉的溶解度和膨胀度与温度有关,均随温度的增加而增大。不同品种绿豆淀粉糊经一次冻融后析水率均较高,随冻融循环次数的增加,析水率均逐渐增大。相关性分析表明,直链淀粉含量与淀粉糊的最终粘度和回生值之间存在显著正相关(r=0.674,r=0.725;p0.05),与膨胀度之间具有极显著负相关关系(r=-0.805,p0.01)。     

Characteristics of Microparticulated Particles from Mung Bean Protein

Mung bean protein was separated from wastewater of mung bean starch factory by utilizing an isoelectric precipitation method. The characteristics of freeze dried protein concentrate (having 88.93% protein content on dry basis) were oil absorption capacity, water absorption capacity, surface hydrophobicity and emulsifying activity index of 5.76 g/g, 2.41 g/g, 30, and 83, respectively. The lab scale procedure for production of microparticulated protein particle (MP³) included heating 5% w/w solution of mung bean protein concentrate in deionized water at 83°C for 15 min, coupled with homogenization at 17,000 rpm, homogenization at 23,000 rpm for 15 min, and centrifugation at 1000 × g for 10 min. The resulting supernatant produced 0.89 g of 0.1–3.0 μm MP³ per g of dry mung bean protein concentrate. Observations of MP³ using SEM showed a particle round shape indicating the potential for MP³ to provide creamy texture in oil-in-water emulsion foods to serve as a fat replacer.     

鹰嘴豆、饭豆、绿豆淀粉性质的比较

以鹰嘴豆、饭豆、绿豆淀粉为对象,研究了不同豆类淀粉的糊化性、膨胀度、溶解度、淀粉-碘复合物的可见光谱、淀粉糊的透明度、冻融稳定性、凝沉性以及沉降体积等性质。结果表明:绿豆淀粉的成糊温度和峰黏度最高,而鹰嘴豆淀粉的热糊稳定性和冷糊稳定性最好;3种淀粉的膨胀度和溶解度均随温度的升高而增加,并且淀粉碘复合物可见光光谱的最大吸收波长都在620 nm左右。绿豆淀粉糊的透明度、冻融稳定性和凝沉性最好,沉降体积最大。     

不同品种绿豆淀粉微观结构和热力学特性的比较

以9个品种绿豆的淀粉为研究对象,利用扫描电镜分析、激光粒度分析、差示扫描量热分析和x-射线衍射分析等现代仪器分析方法,研究了绿豆淀粉的颗粒形貌、结晶结构和热力学性质。SEM分析表明,绿豆淀粉颗粒形状有肾形、椭圆形、凸圆形和小球形等,其颗粒形态在不同品种间没有明显差别。激光粒度分析表明,绿豆淀粉粒径大小在不同品种间有明显差异,其粒径范围为18.46~26.81μm,粒径总平均值为20.71μm。不同品种绿豆淀粉均具有典型的C-型衍射图谱,但其相对结晶度在不同品种间存在明显差别,相对结晶度范围为16.23%~42.39%。DSC测定结果表明,绿豆淀粉的胶凝温度(To、Tp和Tc)和热焓值(?H)在不同品种间存在较大差异,且部分品种间差异显著(p0.05);To、Tp、Tc和?H范围分别为:51.02-63.03℃,64.81~73.04℃,70.04~79.44℃和1.09~1.97 J/g。     

低取代度乙酰化绿豆淀粉的性质

以绿豆淀粉为原料,冰醋酸为乙酰化剂,制备低取代度的乙酰化绿豆淀粉。对乙酰化绿豆淀粉的膨润力、溶解度、凝沉性、透明度、黏性、质构特性等进行研究。结果表明：与原淀粉相比,经过乙酰化处理的绿豆淀粉透明度、膨润力、溶解度均比原淀粉有所增加,糊化温度降低,谷值黏度、末值黏度有所升高,而峰值黏度、衰减值则降低,绿豆淀粉乙酰化后凝胶特性也有所改善。     

Geometric and Mechanical Properties of Mung Bean (Vigna Radiata L.) Grain: Effect of Moisture

In this research, selected geometric and mechanical properties of mung bean grain were evaluated as a function of moisture content. Five levels of moisture content ranging from 7.28 to 17.77% d.b. (dry basis) were used. The average length, width, thickness, arithmetic and geometric mean diameters, sphericity, thousand grain mass and angle of repose ranged from 5.145 to 6.199 mm, 3.760 to 4.474 mm, 3.537 to 4.223 mm, 4.147 to 4.965 mm, 4.090 to 4.893 mm, 0.795 to 0.789, 52.3 to 64.6 g, and 25.87 to 29.38° as the moisture content increased from 7.28 to 17.77% d.b., respectively. The bulk density was found to be decreased from 821.3 to 745.2 kg/m³, whereas the grain volume, true density, porosity, terminal velocity, and projected area were found to be increased from 27.88 to 47.33 mm³, 1230.0 to 1456.7 kg/m³, 30.43 to 46.57%, 4.86 to 5.29 m/s, and 17.48 to 19.26 mm², respectively. There is a 43% increase in surface area from grain moisture content of 7.28 to 17.77% d.b. The static coefficient of friction on various surfaces increased linearly with the increase in moisture content. The rubber as a surface for sliding offered the maximum friction followed by galvanised iron, medium density fibreboard, stainless steel, aluminium and glass sheet. As moisture content increased from 7.28 to 17.77%, the rupture forces values ranged from 67.39 to 39.44 N; 63.86 to 42.18 N, and 53.96 to 41.79 N for thickness (Z axis), length (Y-axis) and width (X-axis), respectively.     

球磨对绿豆淀粉结晶结构和糊流变特性的影响

采用偏光显微镜、X-射线衍射等测试方法，研究了绿豆淀粉在机械球磨过程中结晶结构的变化；运用Brookfield旋转粘度计测得不同浓度的淀粉糊在不同温度和剪切速率下的表观粘度，建立了相应的流变模型。结果表明机械球磨使得淀粉结晶结构受到破坏，由多晶态转变成无定形态；经球磨处理的绿豆淀粉糊仍保持假塑性流体特征，但随着球磨程度的增大，糊稠度大大降低，流动性增加，且越来越趋向牛顿流体特征。     

不同糯性谷物淀粉性质的比较研究

本研究选取圆糯米、血糯米、糯小麦、糯玉米、糯小米(糜子)、糯高梁和糯薏米为原料提取淀粉,比较研究了7种糯性谷物淀粉的性质,为其应用提供一定的参考。结果表明:透光率以糯玉米和糯高粱淀粉最大,为20%左右;糯薏米和糯小麦淀粉较易凝沉;50℃下圆糯米、血糯米和糯玉米淀粉的膨胀势较大;圆糯米淀粉的冻融稳定性最差,而糯小麦、糯玉米、糯小米(糜子)和糯高粱淀粉的较好;糊化温度以糯小米(糜子)淀粉最大,为67.8℃,而圆糯米、血糯米和糯玉米淀粉的糊化温度最小,均为60℃;7种糯性谷物淀粉的峰值粘度、保持粘度和最终粘度以糯小麦、糯高粱和糯薏米淀粉的最大,糯玉米淀粉的最小;由回升值/峰值粘度的大小可知,糯玉米淀粉最不易老化,糯薏米淀粉最易老化;糯高粱、糯小麦和糯薏米淀粉的抗剪切作用较弱,而血糯米和糯玉米淀粉在剪切过后有变稠的趋势。     

赤豆、刀豆、芸豆淀粉性质的比较

以赤豆、刀豆、芸豆淀粉为对象,研究不同豆类淀粉的糊化性、膨胀度和溶解度、淀粉-碘复合物的可见光谱、淀粉糊的透明度、冻融稳定性、凝沉性以及沉降体积等性质。结果表明:赤豆淀粉的黏度最高,而芸豆淀粉的热糊稳定性和冷糊稳定性最好;3种淀粉的膨胀度和溶解度均随温度的升高而增加;淀粉-碘复合物可见光光谱的最大吸收波长都在620 nm左右;赤豆淀粉糊的透明度和冻融稳定性最好,沉降体积最大;芸豆淀粉的凝沉值最小。     

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。     

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。     

Comparative Study on the Starch Noodle Structure of Sweet Potato and Mung Bean

ABSTRACT:  Fine structure of sweet potato starch (SPS) and mung bean starch (MBS) by gel-permeation chromatography (GPC) showed that the amylose in SPS and MBS had 9.0 and 1.8 chains, respectively. The long chains of amylopectin in MBS (A_p-MB) were longer than those of amylopectin in SPS (A_p-SP), but the short chains of A_p-SP were shorter than those of A_p-MB. The structures of starch noodles of sweet potato (SPSN) and mung bean (MBSN) were analyzed by GPC, scanning electron micrograph (SEM), differential scanning calorimetry (DSC), and X-ray diffraction after hydrolysis by acid and enzymes. The results showed that the residues obtained with acid and enzymes in MBSN contained large amounts of high molecular weight fractions, and a relatively small amount of low molecular weight fractions, whereas those in SPSN contained some high molecular weight fractions and large amounts of low molecular weight fractions. SPSN exhibited higher digestibility by HCl, α-amylase, β-amylase, and pullulanase than MBSN. The surface of MBSN was more smooth than that of SPSN and the inside of MBSN contained long, thick, and orderly filaments, while there were many pore spaces inside SPSN from SEM. The DSC thermogram of the resistant residues from both starch noodles after acid/enzyme hydrolysis showed a broad endotherm peak near 100 °C (96 to 115 °C) due to the presence of the complexes of amylose-lipid and lipid-(long chains in amylopectin). Because of a lower content of branched amylose and a higher content of amylopectin in SPS, the structure of SPSN had a less distinct crystalline pattern and higher adhesiveness, whereas there was a higher content of amylose with a little branch and moderate amylopectin in MBS. Thus, the structure of MBSN had a stronger distinct crystalline pattern and good cohesiveness.     

木瓜蛋白酶水解绿豆分离蛋白研究

该文选用木瓜蛋白酶水解绿豆分离蛋白,主要研究pH、温度、酶浓度及反应时间对酶解反应影响,并对酶解液功能特性进行系统研究。实验表明:酶解后绿豆分离蛋白溶解度、乳化能力、发泡能力大大提高,但粘度下降。     

支链聚合度对菠萝蜜种子淀粉凝胶化特性的影响

采用5种菠萝蜜种子淀粉(jackfruit seed starch,JFSS)分离直链淀粉和支链淀粉,马来西亚1号(M1)直链淀粉分别和M1、马来西亚5号(M5)、马来西亚6号(M6)、马来西亚11号(M11)、本地品种(BD)的支链淀粉进行1:1的混合,制备具有不同支链聚合度的凝胶化JFSS(gelatinized JFSS,GJFSS:M1'、M5'、M6'、M11'和BD')。以颗粒形貌、冻融稳定性、热力学性质、糊化特性和短程分子有序度为考察指标,研究不同支链聚合度对JFSS凝胶化过程的影响。结果表明,BD的支链聚合度最高,其次是M11、M6、M5、M1的支链聚合度最低。5种GJFSS样品的微观结构明显从致密(M1')变到疏松(BD')。冻融稳定性结果与微观结构结果一致,高脱水收缩形成致密结构(M1'),低脱水收缩形成松散结构(BD')。随着支链聚合度的增加,凝胶化焓、峰值黏度、谷值黏度、崩解值、最终黏度、回生值和吸光度比降低,但转变温度和糊化温度升高。热力学性质、糊化特性和短程分子序列与微观结构和脱水收缩结果一致,支链聚合度是影响淀粉凝胶化特性的重要结构因素。     

绿豆淀粉糊粘度性质的研究

用Viscograph-E型Brabender粘度计测定了绿豆淀粉糊在不同浓度、pH、糖、盐、明矾、硼砂条件下Brabender粘度曲线的变化情况,研究了其粘度性质及影响因素,为进一步了解绿豆淀粉的特性及开发其应用,提供淀粉科学方面的理论依据。