不同品种稻米淀粉的理化性质与链长分布关系研究

以特糯2072、特优2035、Ⅱ优838和冈优188 4种直链淀粉含量不同的籼稻为材料,采用碱法提取淀粉,通过黏度速测仪(RVA)、激光粒度分析仪及离子交换色谱法研究稻米淀粉的糊化特性、粒径分布与支链淀粉链长组成的相关性。结果表明,4种稻米淀粉颗粒的平均粒径为4.98~5.30μm,与直链淀粉含量呈显著负相关关系(P0.05)。4种稻米淀粉糊化特性差异显著,特优2035具有最高的峰值黏度,而特糯2072的峰值黏度最低。支链淀粉的链长分布影响稻米淀粉的RVA谱特性,成糊温度与DP6-11呈显著负相关关系,与DP12-23呈显著正相关关系(P0.05);崩解值与DP6-11呈极显著正相关关系(P0.01),与DP12-23呈显著负相关关系(P0.05);而消减值与DP≥24呈显著负相关关系(P0.05)。     

灌浆结实期不同温度下早籼稻米淀粉链长分布与结构特征差异分析

 利用人工气候箱设高温（32℃）和适温（22℃）两个典型温度处理，对4个早籼水稻品种在不同灌浆结实期温度下的淀粉链长特征与晶体结构差异进行了分析。结果表明，高温处理下稻米淀粉的长B链（Fr II-1）的比例明显下降，其平均分子聚合度也有所减小，而中等B链（Fr II-2）的比例则有所上升，其余淀粉组分的比例及其平均分子聚合度在不同温度处理下的变化规律则不明显，可能与品种本身的淀粉类型特性有关；对不同温度处理后淀粉的X-衍射图谱分析表明，灌浆结实期的不同温度处理并不影响稻米淀粉的晶体类型，但对淀粉的微晶结构有着一定影响，高温处理下X-衍射图谱中的18?2θ峰相对较高、17?2θ峰相对较低，其变化与稻米淀粉中的长B链含量呈显著负相关，而与中等B链含量呈正相关。     

南粳系列水稻品种的食味品质与稻米理化特性

【目的】 明确3个优良食味南粳品种的主要蒸煮食味品质性状的特点及与亲本间的差异,为水稻优质育种提供理论依据。【方法】 本研究以南粳系列优良食味粳稻品种南粳46、南粳9108、南粳5055及其父本关东194、母本武粳13和武香粳14为试验材料,比较分析稻米理化特性、支链淀粉分支结构、RVA谱黏滞性、热力学特性、米饭食味特性等25个食味品质相关性状的差异,分析稻米理化性状与米饭食味特征值间的关系、化学成分和支链淀粉分支结构与理化特性间的关系。【结果】 3个南粳品种在大多数性状上具有一致性,与常规粳稻亲本武粳13和武香粳14相比,3个南粳品种均具有更小的直链淀粉含量、峰值时间、热浆黏度、最终黏度、回复值、消减值、回生焓、回生率和米饭硬度值,更大的胶稠度、崩解值、米饭黏度值和综合食味值。在支链淀粉分支结构上,3个南粳品种的A链（DP6-12）比例更大,而B1链（DP13-24）更小。3个南粳品种大多数性状均与关东194相似,说明南粳系列品种的食味品质特性遗传自关东194。3个南粳品种中亦存在差异性状,南粳46的蛋白质含量和热力学参数更低,南粳9108的脂肪含量更高,而南粳5055的成糊温度更高。相关性分析表明,除蛋白质含量、糊化温度、峰值时间外,米饭综合食味值与稻米大多数理化性状存在显著或极显著的相关性,而稻米理化特性主要受直链淀粉含量的影响。【结论】 3个南粳品种食味品质的优异特性是具有更低的糊化和回生特性,更高的胶稠度和米饭黏性,更短的糊化时间和更大的崩解性能。较低的直链淀粉含量是其优良食味品质形成的主要原因,而蛋白质含量和支链淀粉分支链比例主要对糊化和回生特性起作用。     

稻米抗性淀粉含量测定方法的比较分析

以高抗性淀粉水稻品种功米3号、粳稻日本晴、中籼品种9311为材料,比较其蒸煮前后抗性淀粉含量的变化,以及在不同pH值下水解后的抗性淀粉含量的差异.研究结果表明,蒸煮前后各材料的抗性淀粉含量依次为:未蒸煮处理＞蒸煮隔夜处理＞蒸煮处理,未蒸煮处理与其他两种处理相比较差异显著,蒸煮隔夜处理与蒸煮处理相比较差异不显著;不同pH...     

优质稻米的特征与影响稻米品质的因素

一、优质稻米的特征加工品质好,糙米率、精米率和整精米高。食味品质好,香味浓、胶稠度高,糊化温度低。直链淀粉含量低等。外观品质好,透明度高、有光泽,垩白粒率和垩白度低,未成熟的青米,茶色米,乳白米,死米极少。无受害的畸型米,无砂粒等杂质。营养品质好,蛋白质含量高。2006     

高抗性淀粉稻米防治慢性病研究进展

本文综述了防治慢性病尤其是糖尿病的研究进展,着重强调了高抗性淀粉稻米新品种选育及其防治慢性病尤其是糖尿病的作用,为高抗性淀粉稻米产业化奠定基础。     

不同类型水稻支链淀粉理化特性及其与米粉糊化特征的关系

【目的】探索稻米中支链淀粉理化特性及其与米粉的糊化特征的关系。【方法】以不同类型水稻代表性品种为材料，测定支链淀粉的蓝值和最大吸收波长，用Sephadex G75层析柱分析支链淀粉分枝链的链长分配，并分析其与稻米RVA谱和米饭质地间的关系。【结果】不同类型代表品种的支链淀粉的蓝值和最大吸收波长存在显著差异，籼型品种稻米支链淀粉的蓝值和最大吸收波长要高于粳型（巴西陆稻除外），非糯性品种支链淀粉的蓝值和最大吸收波长呈极显著的线性关系(r=0.995**)。经Sephadex G75分离的FrⅠ部分的链长的平均聚合度>100 glucose unite，FrⅡ部分的链长的平均聚合度为44～47 glucose unite，FrⅢ部分的链长的平均聚合度为10～17glucose unite。不同类型代表品种支链淀粉中长分枝链与短分枝链的比率存在明显的差异，在供试的糯性品种中，籼糯含长分枝链比粳糯多；非糯性品种中，籼稻比除粳型偏籼的巴西陆稻以外的粳稻含有更多的长分枝链。在同一类型品种中，供试的籼型杂交稻的支链淀粉中含有的长分枝链要比常规稻多，陆稻品种含的长的分枝链要高于水稻品种。支链淀粉的短链部分(FrⅢ)的比率与最高粘度和崩解值呈极显著的正相关关系(r=0.969**, r=0.949**)，而长链部分(Fr(Ⅰ+Ⅱ))与最高粘度和崩解值呈极显著负相关关系(r=-0.969**, r=-0.949**)。【结论】水稻支链淀粉的分枝链长分配与稻米品质关系密切。在非糯性品种中，硬性和凝聚性大、松弛性和粘附性小的品种，米饭的口感表现硬，咀嚼有渣感，其Fr(Ⅰ+Ⅱ)比率大，即支链淀粉所含长分枝链比率高。     

稻米淀粉合成和食味品质改良研究进展

稻米品质主要由碾磨品质、外观品质、蒸煮与食味品质和营养品质等组成.随着生活条件的逐步提升,人们对蒸煮与食味品质优良的稻米需求越来越高.而淀粉是稻米胚乳的主要成分,是影响其食味品质的重要因素,育种家们基于对淀粉合成相关基因与稻米蒸煮食味品质间的关联分析结果,利用常规育种和CRISPR/Cas9等技术创建了一系列具有优良食味品质的水稻新品种(系).本文总结了稻米品质的组成和影响因素、高等植物淀粉的生物合成途径、淀粉合成底物ADPG的转运途径、直链淀粉和支链淀粉的合成途径、淀粉合成基因与稻米蒸煮食味品质改良的关系以及Wx基因等位变异在稻米品质改良中应用的研究进展,为以后稻米蒸煮食味品质改良提供参考.     

稻米抗性淀粉含量及其环境稳定性分析

【目的】食用高抗性淀粉含量稻米虽利于提高慢性病人群的健康水平,但培育出的高抗性淀粉含量水稻品种还较少。开展水稻种质资源抗性淀粉含量及其环境稳定性的研究,为高抗性淀粉含量水稻种质资源发掘和生产应用提供参考依据。【方法】参照爱尔兰Megazyme公司提供的方法测定稻米抗性淀粉含量,用PAST软件完成种质含量分布作图。通过一年多点试验评价抗性淀粉含量的环境稳定性,利用DPS软件完成含量方差分析。依据国家标准GB/T15683-2008分析了稻米直链淀粉含量。【结果】对1 206份水稻种质稻米抗性淀粉含量分析,结果表明,绝大部分水稻种质稻米抗性淀粉含量低,含量低于2.5%的占87.6%,高于10%的仅占约0.2%。稻米抗性淀粉和直链淀粉含量存在显著正相关,但在高直链淀粉含量种质中未出现抗性淀粉含量高的品系,却在低直链淀粉含量种质中发现3份抗性淀粉含量高于10%的品系,其中1个优质软米品种Diangu2的抗性淀粉和直链淀粉含量分别为10.12%和12.3%,综合农艺性状优良,米饭食味性好。在3个不同环境种植18个不同抗性淀粉含量的品系,结果显示有13个品系的含量不受种植环境差异的影响,另5个品系的含量受环境影响,稻米的抗性淀粉含量除了受基因型影响外,还受种植环境、以及基因型与环境互作的影响。【结论】水稻种质资源稻米抗性淀粉含量普遍很低,抗性淀粉含量与直链淀粉含量虽存在显著正相关,但低直链淀粉含量种质中也可能存在高抗性淀粉的品种,所以培育稻米抗性淀粉含量高且食口性好的品种是可能的。稻米抗性淀粉含量主要受基因型控制,在不同环境中含量高的品种依然高,含量低的品种仍然低,那么高含量的品种可在其适种稻区种植生产大米,其含量不会被明显影响。     

不同基因型水稻的抗性淀粉含量与稻米品质性状的相关性及差异性

对不同基因型水稻的米质和抗性淀粉含量进行相关性分析,同时根据各基因型水稻的米质进行了聚类和主成分分析。结果表明,粳稻米质优于籼稻;抗性淀粉含量与直链淀粉含量、垩白粒率有显著的相关性,籼稻中的抗性淀粉含量与品质性状有着更宽范围的相关性;聚类分析以欧式距离24.55为标准,将37份水稻材料分为6类,且具有明显的米质优劣划分;主成分因子对稻米品质的影响程度为:外观品质因子蒸煮品质因子碾磨品质因子,而抗性淀粉可归类到蒸煮品质因子中,对米质影响的贡献率达到19.48%。     

中国不同品种谷子抗性淀粉分布规律

抗性淀粉是谷子中的重要功能成分。对来自中国4个生态区10个省份216个谷子品种抗性淀粉含量进行分析。结果表明,中国谷子地方品种抗性淀粉平均值为2.43%,含量变幅为0.00%~6.74%,变异系数为50.26%,呈偏正态分布;不同生态区谷子抗性淀粉含量从高到低依次为内蒙古高原、华北平原、东北平原、黄土高原,且内蒙古高原和黄土高原之间差异显著(P0.05);不同省份抗性淀粉含量存在一定差异,其中黑龙江谷子抗性淀粉含量显著高于内蒙古和甘肃(P0.05),其他省份间差异不大;不同省份谷子(黑龙江除外)和不同生态区品种谷子抗性淀粉含量以2.00%~4.00%为主。     

菱角淀粉主要性质的研究

为了给菱角淀粉的综合利用提供理论依据和基础数据,对菱角淀粉的化学组成、溶解度、膨胀度、淀粉糊的粘度与老化特性等进行了研究．结果表明,菱角淀粉的直链淀粉含量为15．76％;其淀粉糊的最高粘度值介于玉米淀粉和马铃薯淀粉之间,其他粘度特征值高于玉米淀粉和马铃薯淀粉;糊化温度为80．15℃,高于玉米淀粉和马铃薯淀粉;其溶解度、膨胀度随着温度的增加而增加;4％的淀粉含量对老化特性影响较大,pH 6.0时老化值最大．     

Differences in Starch Chain Length Distribution and Structure Characteristics of Early-Indica Rice Under Different Temperature Treatments During Grain Filling

Effects of temperature during grain-filling on chain length distribution and structure characteristics of 4 early-season indica rice cultivars were investigated under the environment-controlled conditions. The plants at flowering stage were subjected to two temperature treatments until maturity (the mean dairy air temperature, 22 and 32℃ for optimum temperature treatment and high temperature treatment, respectively). The result showed that high temperature during grain-filling significantly decreased the long B-chain content and increased the intermediate B-chain content. But the effect of high temperature on other starch chains appeared to be cultivar-dependant. The crystalline characteristics of rice starch were also affected by temperature during grain-filling. The intensity at 18° 2 θ of X-ray diffraction pattern of rice samples under high temperature was higher than those under optimum temperature, though all rice starches performed A-crystalline type. Moreover, the intensity at 18° 2 θ was positive correlation with intermediate B-chain content and negative correlation with long B-chain content.     

高效液相体积排阻色谱法测定稻米支链淀粉链长的相对分子质量分布

【目的】建立稻米支链淀粉链长相对分子质量分布的高效液相体积排阻色谱法（high performance size exclusion chromatography, HPSEC）的测定方法。【方法】先采用丁醇沉降法分离提纯稻米支链淀粉,纯化后的支链淀粉经异淀粉酶酶解切开分支糖苷键,然后运用HPSEC测定其相对分子质量分布。建立了稻米支链淀粉链长相对分子质量分布的HPSEC分析方法：Shodex SB-G、Shodex SB-803（1 000—100 000）、Shodex SB-802.5（300—10 000）3根凝胶色谱柱串连,柱温40℃;流动相为0.1 mol•L-1 Tris+0.1 mol•L-1 NaCl,pH=7.40,流速0.5 mL•min-1;采用示差折光检测器（Differential refractive index detector, RI）,检测器温度为37℃;待测样品浓度为5 mg•mL-1,进样量20 μL。【结果】本法提纯的稻米支链淀粉：淀粉含量为99.4%、蛋白残余为0.02%、支链淀粉碘复合物最大吸收峰为517 nm,为高纯度支链淀粉。供试大米样品脱分支支链淀粉的平均聚合度（DP）分布在2—120,无杂峰干扰。【结论】试验结果和方法验证表明本方法数据可靠、重复性好、简单易行。     

RVA and Farinograph Properties Study on Blends of Resistant Starch and Wheat Flour

Resistant starch （RS） is the undigested starch that passes through the small intestine to the large intestine. As a functional low calorie additive, it has special applications in the food industry. Rapid visco analysis （RVA） and the Brabender farinograph were used to study the pasting properties and the viscoelasticity of blends of RS （RS3 and RS2） and three wheat flours. The wheat flours represented strong gluten wheat （SGW）, intermediate gluten wheat （IGW）, and weak gluten wheat （WGW） flours, at different levels of RS substitution （0, 5, 10, 15, and 20%）. The influence of RS3 on the control wheat flours and RS-wheat flour blends were consistent with those of RS2. The peak, trough, and final viscosities of RS3-wheat flour blends were higher than those of the corresponding RS2-wheat flour blends. The peak, trough, breakdown, final, and setback viscosities ofwheat-RS blends decreased with an increase in resistant starch contents from 0 to 20% in the blends. The 0-20% RS-wheat flour blends were all able to form doughs. The dough development times, dough stabilities, dough breakdown times, and farinograph quality numbers for the RS-wheat flour blends decreased as the RS proportion in the blends increased. The values for RS-SGW flour blends were the highest, followed by RS-IGW and then RS-WGW flour blends. The water absorption values for RS-wheat flour blends and the mixing tolerance index for RS-WGW flour blends were found to increase significantly with an increasing proportion of RS from 0 to 20%, but the mixing tolerance index for RS-SGW and RS-IGW flour blends showed no significant differences amongst the different ratios. Correlation analysis showed that the Farinograph quality number was highly positively correlated with dough breakdown time, dough stability, and dough development time （r= 1.000, 0.958, 0.894）, and highly negatively correlated with the mixing tolerance index （r =-0.890）. Data from this study can be used for the development of dough-based products. It also pr     

Evaluation of Rice Germplasms for Grain Resistant Starch Content and Its Environmental Stability

【Objective】 It is beneficial for improving the health of chronic patients to eat high resistant starch (RS) content rice, but variety with high grain RS content is still very rare. Evaluations of rice germplasms for grain RS contents and its environmental stability were carried out in this study, and the results could provide a reference for the discovery of rice germplasm resources with high RS contents and its production. 【Method】 Grain RS contents in rice germplasms were detected by the Megazyme method, and used the PAST software to complete the frequency distribution of these contents. The environmental stability of rice RS contents were tested by planting at multiple locations within one year, and its variance analysis were performed with DPS software. Grain amylase contents were tested according to the national standard GB/T15683-2008. 【Result】 The initial evaluations on RS contents of 1206 rice germplasms demonstrated that for most these rice with RS content were very low, and about 87.6% of the rice were less than 2.5%, only about 0.2% were higher than 10%. There was a significant positive correlation between rice RS and amylose content, but high RS variety was not discovered in high amylose germplasms. However, three varieties with RS content higher than 10% were screened in low amylose content germplasms, and one of them was a good quality soft rice variety Diangu2, which has RS and amylose content of 10.12% and 12.3%, respectively. It carried out regional tests for eighteen varieties with different RS contents planting at three very differ environmental conditions. The result of environmental stability analysis indicated that the contents of thirteen varieties were affected by differences in planting area, of the others were affected. Totally, the contents were affected by genotype, planting environment and genotype-by-environment interactions. 【Conclusion】 In this research, most rice resources have low RS content, and also detected a significant positive correlation between rice grain RS and amylase content. Therefore, it is possible to develop rice variety with high RS starch and good taste, according the high RS varieties were identified in low amylose content germplasms. The RS content was mainly affected by genotype, so the varieties with high RS contents were high at different environments, and the lows’ were still low. Then, the varieties with high RS content can grow in its suitable areas to produce rice, and the contents could not be significantly affected.