不同品种糯高粱的品质分析

为明晰各种高粱品种的品质特性,以7种糯高粱品种（编号为G1～G7）为研究对象,对其籽粒的主要组成成分及淀粉特性进行测定和对比分析。结果表明,基于糯高粱籽粒的组成成分,通过聚类分析将7种糯高粱分为A(G1、G2、G6)、B(G3、G4、G5、G7)两个大类。两类糯高粱籽粒的主要组成成分及淀粉特性存在较大差异,淀粉糊化特性受高粱支链淀粉含量的影响最大。B类糯高粱有较高的支链淀粉含量（97.53%～98.71%）,水分（10.46%～12.14%）、蛋白质（9.26%～10.54%）和单宁（1.06%～1.43%）含量均较适宜,但脂肪含量（4.22%～5.33%）略高。B类糯高粱淀粉颗粒略小,部分表面较为光滑,其虽具有较高的起始糊化温度（73.60～74.33℃）、终止温度（84.07～84.37℃）和热焓值（14.42～15.34 J/g）,但具有较低的峰值黏度（281.25～311.25 RVU）、衰减值（189.00～233.25 RVU）和回生值（32.88～39.46 RVU）,因此,B类糯高粱较A类糯高粱品种具有更好的糊化特性,更适用于酿造。     

冻藏处理对糯玉米淀粉微观结构和理化特性的影响

将新鲜糯玉米进行不同冻藏时间(0、10、20、30 d)的处理,通过傅里叶红外光谱仪、便携式拉曼光谱仪、X射线衍射仪、扫描电镜、差示扫描量热仪、快速黏度分析仪等研究冻藏处理对其内部淀粉微观结构和理化性能的影响规律,以期为延缓其品质劣变提供基础数据。结果表明：冻藏处理导致糯玉米淀粉的R_{1 045/1 022}减小,半峰宽增大,相对结晶度降低,淀粉颗粒表面出现凹陷和破碎,粒径变小,且随着冻藏时间的延长,冻藏对玉米淀粉微观结构的破坏更加明显;糯玉米经冻藏处理后,其淀粉的糊化温度、糊化焓值、峰值黏度、崩解值下降,最终黏度和回生值升高,表明冻藏淀粉更容易发生糊化,且糊化黏度降低,但淀粉热糊的稳定性有所提高,更容易发生老化。此外,冻藏处理还可导致玉米淀粉内的抗性淀粉和慢消化淀粉转变为快消化淀粉,表明冻藏具有提高鲜食玉米的消化速率和程度的潜力。     

不同品种和粒度对米粉糊化特性及米蛋糕品质的影响

为研究不同品种和粒度米粉对米蛋糕品质的影响,选取粳米、籼米、糯米三个品种,分别制备80、100、120、140目的米粉。通过测定不同品种和粒度米粉的糊化特性、米蛋糕的质构特性和感官品质等,采用定性方法分析得出不同品种和粒度米粉对米蛋糕品质的影响。结果表明:随着目数的增加,米粉小颗粒受到的机械损伤增大,水分迅速蒸发,米粉的水分含量逐渐减小;小颗粒粉体更容易吸水膨胀,糊化温度逐渐减小。而衰减值和回生值逐渐增大,峰值黏度和最终黏度先增大后减小;随米粉目数的增加,米蛋糕的咀嚼性逐渐减小,而硬度和弹性逐渐增大,内聚性和感官评分先增大后减小;不同品种米粉的糊化特性、老化特性以及蛋糕品质等均存在差异,米粉粒度对蛋糕品质具有一定的影响。在过筛目数为120目时,蛋糕的感官得分达到最高。当米粉过筛目数在140目粒径较小时,质地过于松软,食用时咀嚼性差,口感欠佳,蛋糕品质下降。相比于糯米粉而言,粳米粉和籼米粉更适宜制作蛋糕,由粳米粉为原料制作的蛋糕品质更好。综上所述,过筛目数为120目的粳米粉更适合制作蛋糕。     

氯化钠对不同品种红小豆淀粉特性的影响

从3种不同品种的红小豆中提取的淀粉为原料,通过分析淀粉及添加氯化钠后的淀粉糊的粒径、黏度值、回生值、热焓值、凝胶性等特性,探究氯化钠对淀粉糊化特性的影响。结果表明:低直链淀粉含量的大红袍中淀粉相较于宝清红和珍珠红淀粉,表现出较高的糊化起始温度、最终黏度、热焓值;较低的峰值黏度、较小的粒径;对比添加2%氯化钠前后,3种红小豆淀粉糊化后的平均粒径、峰值黏度、衰减值和回生值显著下降(P0.05);糊化温度、淀粉的凝沉性显著增大(P0.05);氯化钠对凝胶特性的影响体现在凝胶强度显著降低(P0.05),同时淀粉凝胶的黏度减小。     

杂交籼稻亲本对其理化特性及食味品质的影响

为研究杂交籼稻亲本对白米理化特性及其食味品质的影响,检测45个品种白米的基本理化指标、糊化特性、米饭食味值与稻米亲本进行数据分析。结果表明：比较变异系数发现,恢复系和不育系对指标的影响不同,恢复系品种影响的指标占所有指标的57.14%,不育系品种影响的指标占所有指标的78.57%,其中恢复系品种907、3168,以及不育系品种广8A、931A影响的指标数均为92.86%;相关性分析发现,不育系对品质影响达到显著水平以上的指标数高于恢复系,其中不育系931A对稻米弹性、外观和口感的影响达到极显著水平;通过聚类分析可知,不育系广8A、76S、圳S、2311S、931A对大米品质的影响较强,同不育系的不同恢复系品种各项指标差别较小。综合3种统计分析方式可以发现,不育系亲本对大米和米饭品质的影响强于恢复系亲本,不育系亲本中广8A、76S、931A的影响作用最强。     

糯小麦粉特性研究进展

由于糯小麦粉几乎不含直链淀粉,所以在食品工业和非食品工业上将有重要的应用价值.综述了近几年国内外糯小麦育种、糯小麦淀粉特性和糯小麦配粉研究进展.并阐述了其在食品工业中的开发和应用.     

不同品种绿豆的淀粉品质特性研究

为研究绿豆淀粉品质的品种变异性并从中筛选适宜加工的优良品种,选取我国16个绿豆品种,从中提取淀粉,并对淀粉的基本组成、糊化及凝胶特性进行了对比分析。结果表明,不同绿豆品种的总淀粉、直链淀粉及抗性淀粉含量存在不同程度的差异,其中总淀粉差异最小(变异系数2.32%)、抗性淀粉最大(变异系数22.77%),直链淀粉变幅为23.65%～34.08%。淀粉的糊化特性中,成糊温度的品种间差异最小、破损值差异最大,变幅分别为66.8～72.1℃及4.5～46.5 BU。凝胶特性中,硬度、黏附性和咀嚼度的差异尤为显著(变异系数>40%)。在所选取的绿豆样品中,中绿1号的淀粉易糊化,且淀粉糊的热稳定性强;郑绿8号及中绿10号的淀粉易老化、凝胶硬度大、弹性好。     

糯小麦与非糯小麦面粉糊化特性的比较

淀粉是小麦籽粒的重要组成部分,约占小麦粒重的70%～75%。淀粉糊化特性的不同是区分小麦类型、判断小麦淀粉品质特性的重要依据。实验以农大糯麦1号、糯227等5个糯麦品种及非糯小麦品种京411为材料,利用RVA测试其糊化特性,结果表明,糯麦与非糯小麦在峰值黏度、峰值时间、糊化温度等糊化特性参数上存在显著差异,而峰值黏度与小麦的糯性与否无关。     

河南省主要种植小麦品种淀粉特性研究

采用小麦籽粒湿法分离淀粉技术，分离提取河南省种植的36种小麦和4种国外商品小麦的淀粉，计算出淀粉提取率．小麦淀粉提取率与品种有关；分析了这些淀粉样品的水分、脂类、蛋白质和直链淀粉含量，采用快速粘度分析仪(RVA)测定淀粉糊特性，测定了淀粉糊流变学特性，进行了回归分析和聚类分析，以淀粉的流变学特性为基础，进行了分类对比。发现安农98005与澳洲商品软麦具有相近的淀粉特性。     

糯小麦“山农糯麦1号”籽粒及淀粉品质分析

为更好地了解糯小麦的品种特性,以山东省第一个审定的高产糯小麦“山农糯麦1号”为材料,研究其籽粒和淀粉特性。结果发现：该品种几乎不含直链淀粉（仅0.1%）,较普通小麦具有较高的蛋白质含量（16.4%）和面粉白度（81.2%）。扫描电镜观察淀粉粒度分布不均匀,A型淀粉颗粒较多。快速粘度分析（RVA）测定表明淀粉具有较低的糊化温度,较短的糊化时间,较低的峰值黏度、最终粘度和回生值。加工时面团吸水率明显较高,形成时间大于稳定时间。这些结果将为山农糯麦1号适于用作配粉和加工食品提供参考依据。     

Pasting Properties of Potato Starch and Waxy Maize Starch Mixtures

The pasting viscosity, morphological properties, and swelling properties of potato starch and waxy maize starch mixtures at different ratios were investigated. Pasting analysis of the starch mixtures (7% solids in water, w/w) using a Rapid Visco Analyser showed linear changes in peak viscosity and pasting temperature according to the mixing ratios of both starches, but not in breakdown and setback. The pasting profile revealed that the starches rendered mutual effects during pasting, more significantly when the amounts of potato and waxy maize starches were similar. The volume fraction of swollen granules and the presence of amylose appeared to be important parameters in the mutual effects of both starched during pasting. Under a light microscope, the swelling of potato starch granules was delayed by the presence of waxy maize starch. Overall results indicate that new pasting properties can be generated by mixing starches of different botanical sources.     

Properties of Korean Amaranth Starch Compared to Waxy Millet and Waxy Sorghum Starches

Characteristics of waxy type starches isolated from amaranth, waxy millet and waxy sorghum harvested in Korea were evaluated. Shapes of all starch granules were polygonal or slightly round and the surfaces of waxy millet and waxy sorghum starch granules showed visible pores. Amylose contents of the three starches were between 3.2–6.0% and amaranth starch showed the highest water binding capacity (WBC) (130.7%). The swelling power and solubility of amaranth starch studied at 65.0–95.0°C increased about 13.7‐ and 14.0‐fold, respectively, with increase in temperature. Swelling power of waxy sorghum starch was the highest (72.6 at 95°C) among the starches studied, while amaranth starch had a constant swelling power and its rate of solubility increasely only slowly at temperatures higher than 75°C. From RVA data, initial pasting temperatures of amaranth, waxy sorghum and waxy millet starches were 75.7, 73.3 and 75.2°C, respectively. Peak viscosity, breakdown, and setback from trough of amaranth starch were 68.3, 16.7 and 7.5 RVU, respectively, which were the lowest values among the starches investigated. Using DSC, onset temperature of gelatinization of amaranth starch was 1.5–4.0°C higher than those of waxy sorghum and millet starches, corresponding to the RVA result. The enthalpies of gelatinization of the starches studied in our laboratory were in the range of 8.5–12.7 J/g with decreasing order of waxy sorghum > amaranth > waxy millet starch.     

Crystallinity and Pasting Properties of Freeze‐Thawed High Amylose Maize Starch

Native and defatted high amylose (about 70%) maize starch gels were freeze‐dried or repeatedly freeze‐thawed, and the effects of the treatments on the crystallinity, pasting viscosity, and resistance to digestive enzymes of the dried starch were examined. Both native and defatted starches showed a B‐type crystal structure in the X‐ray diffractogram, but the crystallinity was decreased by repeating the freeze‐thawing cycle. In the DSC thermogram, the freeze‐thawed starches exhibited two endothermic transitions in the temperature ranges of 90—110 °C and 130—160 °C, representing amyloselipid complexes and amylose‐amylose double helix crystals, respectively. By defatting, the melting enthalpy for the amylose double helices was increased, indicating that the residual lipids inhibited the amylose crystal formation. Ice crystals in the starch gel matrix became smaller and the ice cell membrane became thinner as freeze‐thawing was repeated. The freeze‐dried or freeze‐thawed starch powders swelled to a paste by heating in water as did typical granular starch, but the setback by cooling was significantly high due to the rapid retrogradation of leached amylose. By the treatments, the resistance of the starch to digestive enzymes was also raised. The defatted starches displayed greater paste viscosity and resistance to digestive enzymes than the native starches. But the overall viscosity was decreased as the number of freeze‐thawing cycles increased.     

Physicochemical Properties of Waxy and Normal Maize Starches Irradiated at Various pH and Salt Concentrations

Waxy and normal maize starches of various pH values and salt contents were prepared, irradiated with gamma rays (5–20 kGy) and their molecular structure, pasting viscosity and rheological properties determined. Average molar mass and size of both waxy and normal maize starches decreased considerably by irradiation from >338.0×10⁶ to <39.4×10⁶ g/mol and from >237.5 to <125.2 nm, respectively. Adjustments of pH had little influence on the average molar mass and size of irradiated starch, whereas incorporation of salt greatly reduced the molar mass and size of irradiated waxy and normal maize starches. As the pH increased from 4 to 8, the pasting viscosity of the irradiated starches decreased from 1032 to 279 mPa s in waxy and from 699 to 381 mPa s in normal starches. Pasting viscosity of both irradiated waxy and normal starch decreased from 689 to 358 mPa s and from 327 to 184 mPa s as the salt concentration increased from 1 to 5%. The G′ of gels, determined during cooling from 90 to 10°C or storage for 8 h, decreased in irradiated waxy and normal starches by pre‐conditioning at pH 8 and in irradiated waxy starches by pre‐conditioning at 5% NaCl. With 5% NaCl, G′ of irradiated normal maize starch during cooling increased up to the irradiation level of 10 kGy, and increased during storage for 8 h at all levels of irradiation. Incorporated salt prior to irradiation appears to induce incremental modifications in the molecular structure, rheological and retrogradation properties of starch by boosting the degradation of molecules.     

Pasting,Color, and Granular Properties of Starches From Local and Improved Cassava Varieties in High Rainfall Region of Nigeria

This study investigated the pasting, color, and granule properties of starches produced from 39 different cassava varieties (36 varieties resistant to cassava mosaic disease and three checks, TMS 30572, 4(2) 1425, and 82/00058) in two planting seasons at the experimental farm of the International Institute of Tropical Agriculture, Onne, Rivers State, Nigeria. Varieties screened showed significant seasonal differences (p?<?0.05) in all the properties over two harvesting seasons. The peak viscosity during heating ranged from 241.13 RVU to 485.21 RVU in year 1 and from 232.46RVU to 407.63RVU in year 2. Pasting time of the different starches ranged from 3.20–3.70 min in year 1 and from 3.6–4.2 min in year 2. Pasting temperature of the different starches ranged from 63.93–65.35 °C and from 73.15–77.15 °C in the years 1 and 2, respectively. Starch color intensity ranged from 85.05–94.49% in year 1 and from 90.27–92.96% in year 2. The structure of starches from cassava varieties was round in shape with granule size ranging from 12.50–22.50 μm in two years with varieties 97/0211 and 98/0510 as the smallest and variety 96/1632 as the largest. This study, therefore, showed that there were significant genotypic and seasonal variations in the pasting, color, and morphological properties of native starches from cassava.     

NaCl对氧化淀粉浆料糊化性能的影响

研究NaCl对氧化淀粉浆料糊化性能的影响。采用快速黏度仪(RVA)测试了不同NaCl浓度下氧化淀粉的糊化温度、糊化时间、峰值黏度、终值黏度和回生值。结果表明:随着NaCl对淀粉质量浓度的增大,氧化淀粉的糊化温度、糊化时间和峰值黏度逐渐增大;终值黏度和回生值随着NaCl对淀粉质量浓度的增大,先减小后增大;NaCl对淀粉质量浓度在2%～6%的范围内时,淀粉浆液的低温稳定性和抗老化性能有所提高。     

羟丙基糯玉米淀粉合成工艺及性能研究

本文以糯玉米淀粉为原料，以环氧丙烷为醚化剂、氢氧化钠为催化剂、硫酸钠为抑制膨胀剂，对糯玉米羟丙基淀粉合成工艺及其性能进行了研究，探讨了糯玉米淀粉乳浓度、环氧丙烷用量、反应时间、反应温度、氢氧化钠用量及硫酸钠用量对糯玉米羟丙基淀粉取代度和反应效率的影响。实验结果表明，增加环氧丙烷用量、延长反应时间，可使羟丙基淀粉取代度增加。对糯玉米羟丙基淀粉的冻融稳定性、透明度及粘度进行研究表明，随着羟丙基糯玉米淀粉取代度的增加，其冻融稳定性和透明度增加，但粘度却降低。     

播期对糯玉米籽粒产量和淀粉热力学特性的影响

以4个糯玉米品种(垦粘1号,苏玉糯2号,苏玉糯5号和渝糯7号)为材料,研究了播期对其籽粒产量与淀粉热力学特性的影响.结果表明:各品种在5月15日播种时受飞虱危害不能正常成熟,能正常成熟时籽粒产量均在4月15日播种时最低,垦粘1号和苏玉糯2号在6月15日播种时最高,苏玉糯5号和渝糯7号则在7月15日播种时最高.播期对淀粉热力学特征值的影响远高于品种间差异(回生值除外).总体上,回生值受播期影响较小,热焓值和峰值指数以3月15日播种时最高,6月15日播种时最低,起始温度、峰值温度和终值温度以4月15日播种时最高,7月15日播种时最低,糊化范围4月15日播种时最低,6月15日播种时最高.不同品种籽粒产量和淀粉热力学特征值对播期的响应有显著基因型差异.碘结合力播期处理的变化趋势与转变温度3个指标相似.相关分析表明,碘结合力与起始温度、峰值温度、终值温度和峰值指数显著正相关,与糊化范围显著负相关.     

乳熟期玉米糊化热力学性质的分析

利用差示扫描量热仪(DSC)对18种乳熟期玉米的糊化热力学性质进行研究,探讨玉米中主成分(水分,直链淀粉,支链淀粉及蛋白质质量分数)对其糊化热力学行为的影响,分析其成分与玉米糊化热力学参数之间的相关性。结果表明:水分质量分数、直链淀粉和支链淀粉的质量分数与起始糊化温度(T0)、峰值糊化温度(TP)均为极显著正相关,而与终止糊化温度(TC)、热焓值(ΔH)的相关性均不显著;此外,热焓值(ΔH)与终止糊化温度(TC)是极显著相关。     

糯小麦配粉对小麦粉及面包品质影响的研究

采用不同的配比将糯小麦粉加入到小麦粉中,通过测定一系列小麦粉指标和面包指标,研究了糯小麦配粉对小麦粉及面包品质的影响.结果表明:随着糯小麦粉比例的增加,支链淀粉含量、支直比、湿面筋含量、沉降值、弱化度增加;直链淀粉含量、总淀粉含量、降落数值、形成时间与稳定时间下降;小麦粉的峰值黏度、最终黏度与回升值都逐渐降低,而糊化温度变化不显著;将5%～10%的糯性小麦粉添加到面包粉中生产面包,面包的体积与综合得分略有下降,但面包的吸水率与保水性能增加,抗老化性能有所增强,有利于面包货贺期的延长.