糯小麦粉与普通小麦粉配粉糊化特性的研究

选用糯小麦品种中糯一号与普通小麦(非全糯小麦)品种豫麦47、温6和澳大利亚优质面条小麦品种Gamenya,进行籽粒蛋白质含量、淀粉含量及直链淀粉含量的测定。并将中糯一号面粉分别与豫麦47、温6面粉配粉,进行了RVA试验(快速粘度分析),研究了三种单一品种面粉及其配粉的糊化特性。结果表明:中糯一号籽粒蛋白质含量、淀粉含量与供试普通小麦品种相近。但其直链淀粉含量很低,仅为1. 45%,远低于供试普通小麦品种。在RVA试验中,中糯一号面粉糊化快,峰值时间比普通小麦缩短了一半,其粘度下降到低谷后,粘度曲线变化平缓,回冷值很小,明显与供试普通小麦不同。糯小麦与普通小麦配粉的粘度曲线呈双峰状,其粘度参数因糯、普小麦配粉比例不同而不同。总之,在普通小麦粉中加入糯小麦粉后,面粉直链淀粉含量和糊化特性发生了变化,对面制食品品质将产生一定的影响。     

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。     

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。     

小麦淀粉品质的研究

测定了河南省22个小麦品种(样品)的籽粒蛋白质、淀粉与直链淀粉含量,并采用快速粘度分析(RVA)测定了这些品种的面粉糊化特性.参照国内外研究结果综合鉴评认为在供试的小麦品种中,温6(稻茬)、豫麦47、郑农7号、豫麦52、百农64、周麦12等具有适于制作优质面条的淀粉品质;同时观察到同一品种在不同种植条件下,其蛋白质含量、直链淀粉含量和淀粉品质有很大差异.进一步证明了在优质小麦生产中选择适宜种植地区和采用适宜栽培技术的重要性.     

小麦淀粉的理化特性及其与面制品品质的关系

综述了小麦淀粉的主要特征，糊化、粘度和凝沉性等理化特性；研究了小麦淀粉中直链淀粉含量、破损淀粉含量、膨胀特性和糊化、粘度特性等与面制品蒸煮品质、烘焙品质的关系及其影响机理，结果表明：在小麦淀粉品质性状中，粘度参数和膨胀势等对面制品品质有较大影响，直链淀粉含量对面条品质有负作用，糊化温度影响面制品的制作工艺过程，破损淀粉含量对面制品品质也有一定影响。     

小麦籽粒淀粉品质与蛋白质品质关系的初步研究

通过测定32个小麦品种籽粒的11个淀粉品质性状及10个蛋白质品质性状，分析了各性状之间的简单相关关系。结果表明：直链淀粉含量与清蛋白含量显著正相关，与支链淀粉含量、膨胀势、高峰粘度、衰减值、粗蛋白含量、醇溶蛋白含量、谷蛋白大聚合体含量、沉降值显著负相关；支链淀粉含量与糊化温度显著负相关，与沉降值、面筋指数显著正相关；膨胀势、高峰粘度、低谷粘度、最后粘度两两间极显著正相关；衰减值与醇溶蛋白含量、谷蛋白大聚合体含量、沉降值，糊化温度与球蛋白含量呈显著正相关；回生值与面筋含量，峰值时间与沉降值显著负相关。文章还分析了淀粉品质和蛋白质品质与蒸煮类食品品质的关系。     

不同Wx蛋白重组类型对普通小麦直链淀粉含量及RVA参数的影响

小麦Wx蛋白是控制直链淀粉合成的关键蛋白,与淀粉品质的关系密切.为了明确Wx蛋白的重组对小麦直链淀粉含量及RVA参数等淀粉品质指标的影响,本研究选择非糯与糯性小麦组配杂交组合,利用SDS-PAGE检测了杂交后代的Wx蛋白重组类型,并测定了不同重组类型的直链淀粉含量、膨胀势和RVA参数等淀粉品质指标,结果表明Wx蛋白全缺失型的直链淀粉含量显著低于野生型、单缺失型和双缺失型;膨胀势检测中,Wx蛋白全缺失型的均值较其他重组类型低,但多重比较结果表明不同Wx蛋白重组类型对膨胀势的影响差异不大;不同RVA参数中,Wx蛋白重组类型的作用大小不同,在峰值黏度指标中,全缺失型的影响最大,野生型、单缺失型、双缺失型间的作用相近;低谷黏度和最终黏度指标中,野生型与全缺失型的影响差异较大,其他重组类型的作用相近;在稀懈值、反弹值、峰值时间、糊化温度四个指标中,Wx蛋白重组类型间的作用没有太大差异.     

湖南省10种早籼稻直链淀粉含量和糊化特性的研究

取湖南省10种广泛种植的早籼稻样品,采用国标方法测定其直链淀粉含量;用快速粘度分析仪(RVA)测定其糊化特性;使用SPSS软件和PCA分析法对数据进行分析。结果表明:不同品种早籼稻的直链淀粉含量和糊化特性主要特征值均有明显差异,变异系数范围较大(0.83%~32.30%),糊化特性参数值之间互相影响。10种早籼稻直链淀粉含量的变化范围为16.12%~24.80%,依据直链淀粉含量划分了10种早籼稻的归属类型,有高含量型、中含量型和低含量型,没有出现极低含量型和糯型。采用PCA分析法把7个糊化特性参数归于2个主成分,分别为峰值粘度因子和峰值时间因子。依据这两个主成分作出主成分载荷图,实现区分不同产地的样品,以及所属直链淀粉含量类型不同的样品。     

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。     

玉米籽粒品质性状及其相互关系分析

通过测定55个玉米品种（系）籽粒的物理性状、淀粉品质及蛋白质组分，分析它们之间的简单相关关系。结果表明：容重与各淀粉组分含量呈负相关，与角质率、低谷粘度、最终粘度、回冷值、峰值时间、糊化温度呈极显著正相关；角质率与醇溶蛋白、谷蛋白、总蛋白含量及峰值时间和糊化温度呈极显著正相关，与膨胀势、峰值粘度和稀懈值呈显著负相关；直链淀粉含量与稀懈值负相关，与膨胀势、峰值粘度、低谷粘度、最终粘度、回冷值、峰值时间和糊化温度均表现一定的正相关；支链淀粉含量、总淀粉含量以及支／直比与糊化温度正相关，与其它粘度指标负相关；峰值粘度与低谷粘度、稀懈值、最终粘度和回冷值的相关程度较高，是衡量淀粉糊化特性的最重要指标；醇溶蛋白与总蛋白和粘度性状问的关系更密切，醇溶蛋白含量的变化对于总蛋白含量变化及淀粉特性的影响最大。文章还提出今后要加强支链淀粉、峰值时间、糊化温度和醇溶蛋白含量等对加工品质影响的研究。     

Physicochemical Characteristics of Starches of Two Sets of Near‐isogenic Wheat Lines with Different Amylose Content

Wheat lines with modified amylose content were produced by controlling the null alleles of three homoeologous Wx loci, Wx‐A1, Wx‐B1 and Wx‐D1 and those with triple‐null Wx alleles were found to yield waxy, amylose‐free starch. In this study, the new near‐isogenic lines developed by the recurrent backcross method between cv. Kanto 107 and the waxy mutant lines, K107Wx1 or K107Wx2, were cultivated and the physicochemical characteristics of their starches were investigated. The apparent amylose contents of the waxy near‐isogenic lines were 1.6 – 3.8%, whereas those of the non‐waxy near‐isogenic lines were 23.2 – 25.4%. The waxy lines had higher gelatinization temperature and enthalpy than the non‐waxy lines and no peak of amylose‐lipid complex as determined by DSC. The X‐ray diffraction patterns from both waxy and non‐waxy near‐isogenic lines corresponded to A‐type crystallization, like their parent lines. The starches isolated from the waxy lines had lower pasting onset and peak temperatures, higher peak viscosities and breakdown and lower final viscosity than those of the non‐waxy lines in the Viscoamylograph. The starch of non‐waxy near‐isogenic lines had lower peak and final viscosities and higher breakdown than did the recurrent parent line, cv. Kanto 107. The characteristics of the new wheat starches were well understood and classified, which will contribute to the wide application of these starches in food processing.     

Combining high‐amylose and waxy starch mutations in barley

Inbred lines, from a cross between barleys carrying the waxy and high‐amylose genes respectively, were characterised by the presence of both, either or neither of the genes and grown under field conditions. Starch granule proteins were separated by SDS‐PAGE and lines carrying the waxy gene, with or without the high‐amylose gene, had greatly reduced intensities of the 60 kDa band associated with granule‐bound starch synthase. One representative sample of each starch type was also grown under two controlled environment (CE) regimes. Starch properties were assessed on field‐ and CE‐grown samples of these genotypes and large differences were observed among starch types. Growth conditions generally had comparatively little effect on the starch properties measured. The waxy and high‐amylose genes appeared to have additive effects, both in reducing modal granule size and in increasing gelatinisation temperature significantly above that observed when only one of the genes was present. The genotype with both mutations produced a starch with phosphorus content and blue value, after removal of lipid, slightly higher than those of the waxy type and with an RVA profile similar to that of the wild type, but with lower peak and final viscosities. © 2001 Society of Chemical Industry     

Comparison of the starch properties of Japanese wheat varieties with those of popular commercial wheat classes from the USA,Canada and Australia

The starch properties of four Japanese wheat varieties/breeding lines suitable for both bread and noodles were compared with those of popular commercial wheat classes from the USA, Canada and Australia. All starches were analyzed for amylose content, pasting properties measured by a rapid visco analyzer (RVA), swelling power, thermal properties measured by differential scanning calorimetry (DSC), enzyme digestibility, and chain length distribution of amylopectin (DP 6–17). All starch characteristics studied, except the chain length distribution of amylopectin, were significantly different among the tested wheat classes and varieties/breeding lines. Including Japanese wheat varieties/breeding lines, higher amylose contents and lower peak viscosities were found in hard wheats than in soft wheats. Interestingly, enthalpy, in the amylose–lipid complex measured by DSC, showed significant correlations with the pasting temperature from the RVA and swelling power.     

RVA study of mixtures of wheat flour and potato starches with different phosphorus contents

A rapid visco analysis (RVA) system was used to study the pasting properties of mixtures of wheat flour and potato starches with high phosphorus (HPS), medium phosphorus (MPS) and low phosphorus (LPS) contents, different granule sizes and different amylose contents. The peak viscosities, trough and breakdown, final viscosities, setback viscosities and peak times of control potato starches were found to be higher than those of wheat flour. The peak viscosities were increased significantly with increase of potato starches in the mixtures. Thus, the peak times decreased with increase of potato starch in the mixtures. The breakdown viscosities increased significantly with increase of potato starches in the mixtures and the values were found to be higher in HPS-wheat, followed by MPS-wheat and LPS-wheat mixtures. The final viscosities of HPS-wheat mixtures were highest, followed by MPS-wheat and LPS-wheat mixtures. The setback viscosities of LPS-wheat were significantly higher than those of MPS-wheat and HPS-wheat mixtures at 30 to 50% potato.     

Effect of Fiber Degrading Enzymes on Wet Milling and Starch Properties of Different Types of Sorghums an Maize

A factorial experiment (4 × 2 × 2) was carried out to study the effect of a fiber degrading enzyme complex on starch yield, SO₂ steeping time and starch properties of normal red sorghum (RS), heterowaxy (WHWx) and waxy (WWx) white sorghums compared to regular yellow maize (YM). Starch yields and total starch recovery for the sorghums ranged from 53–64% and 70–85%, respectively. Sorghum starch recovery values were significantly lower (p < 0.05) than maize (66% starch yield and 88% recovery). However, the WWx yielded more starch with lower protein and ash contents (P < 0.05) than the RS and WHWx sorghums. In the RS, the fiber degrading enzymes reduced steep time while owing the same starch recovery. The WWx starch required lower temperature to initiate gelatinization and had higher peak viscosities and lower retrogradation than the other starches. The WHWx starch had intermediate viscoamylograph properties between the regular and waxy starches.     

Milling and flour pasting properties of waxy endosperm mutant lines of bread wheat (Triticum aestivum L)

Two waxy endosperm mutant lines, K107Wx1 and K107Wx2, derived from a bread wheat cultivar, Kanto 107, had a lower flour yield in test milling and a lower peak temperature in flour pasting measurement than their parent. Starch content in the kernel of waxy mutants was low, while fat and (1→3),(1→4)‐β‐D‐glucan content was high compared with cv Kanto 107, but protein content was similar for all of them. Waxy mutants had less α‐amylase activity than their non‐waxy parent, and had lower peak viscosity of flour paste in the pasting medium of water. A pasting test in silver nitrate solution increased peak viscosity in both waxy and non‐waxy flours. The viscosity of waxy flour paste rapidly increased above 60°C, while that of non‐waxy flour paste increased gradually at 60–80°C. The difference in pasting behaviour was attributed to the presence of amylose in starch granules. © 1999 Society of Chemical Industry     

Effect of Fiber Degrading Enzymes on Wet Milling and Starch Properties of Different Types of Sorghums and Maize

A factorial experiment (4 × 2 × 2) was carried out to study the effect of a fiber degrading enzyme complex on starch yield, SO₂ steeping time and starch properties of normal red sorghum (RS), heterowaxy (WHWx) and waxy (WWx) white sorghums compared to regular yellow maize (YM). Starch yields and total starch recovery for the sorg-hums ranged from 53—64 % and 70—85 %, respectively. Sorghum starch recovery values were significantly lower (p < 0.05) than maize (66 % starch yield and 88 % recovery). However, the WWx yielded more starch with lower protein and ash contents (p < 0.05) than the RS and WHWx sorghums. In the RS, the fiber degrading enzymes reduced steep time while producing the same starch recovery. The WWx starch required lower temperature to initiate gelatinization and had higher peak viscosities and lower retrogradation than the other starches. The WHWx starch had intermediate viscoamylograph properties between the regular and waxy starches.     

Physicochemical and Functional Properties of Tetraploid and Hexaploid Waxy Wheat Starch

Waxy wheats possess unique starch functional properties that may be useful in specific end‐uses. To assess the physicochemical, thermal, and pasting properties, starches from seven waxy genotypes originating from two wheat classes, tetraploid durum and hexaploid hard red spring (HRS), were evaluated and compared with their counterpart non‐waxy wild types. The amylose content ranged from 2.3% to 2.6% in waxy durum lines, compared to 29.2% in normal durum control, and 2.1% to 2.4% in waxy HRS, compared with 26.0% in normal HRS control. Significant differences in the degree of crystallinity were observed between the waxy and control starches, despite similar A‐type X‐ray patterns, although differences between the two wheat classes were non‐significant. Both, control and waxy starches displayed an X‐ray peak corresponding to the amylose‐lipid complex, but the intensity of the peak was markedly lower in the waxy starches. The waxy durum starches exhibited the highest transition temperatures as measured by Differential Scanning Calorimetry (DSC), whereas, the enthalpy of gelatinization of most waxy genotypes was statistically higher than that of the controls. All waxy starches displayed high peak viscosity, high breakdown, and low setback profile as measured by the Rapid Visco Analyser (RVA). Texture analysis of RVA gels revealed significant differences between waxy and non‐waxy wheats, as well as between waxy tetraploid and hexaploid wheats, confirming that the nature and class of wheat starch would play a significant role when using waxy wheat blends in different wheat‐based products.     

Changes in kernel properties,in situ gelatinization,and physicochemical properties of waxy rice with inhibition of starch branching enzyme during cooking

The kernel properties, gelatinisation and physicochemical properties of rice were investigated in a waxy rice Guang-ling-xiang-nuo (GLXN) and its transgenic line GLXN-RNAi with inhibition of starch branching enzyme I/IIb. The volume swelling, water content and leached material of cooked kernels increased with increasing cooking time, but they were lower in GLXN-RNAi than in GLXN. The kernels of GLXN-RNAi were more difficultly gelatinised and disrupted than those of GLXN during cooking. The starch in the exterior of GLXN-RNAi endosperm was not completely gelatinised. The C_A-type starch of GLXN-RNAi was more resistant to cooking than A-type starch of GLXN. The cooked kernels of GLXN-RNAi had lower rapidly digestible starch and greater slowly digestible starch than those of GLXN. Brown rice flour had higher peak, hot, final and setback viscosities and lower breakdown viscosity in GLXN than GLXN-RNAi. These results indicated that GLXN-RNAi kernels exhibited great potential in applications as health foods.     

Comparison of Endosperm Starch Granule Development and Physicochemical Properties of Starches from Waxy and Non-Waxy Wheat

Starch granule development and physicochemical properties of starches in waxy wheat and non-waxy wheat were investigated in this article. Starch granules in waxy wheat endosperm showed an early developmental process. Compared with non-waxy wheat starch granules (round-shaped), waxy wheat starch granules (ellipse-shaped) were larger and contained more B-type granules. According to the granule size, starch granules were divided into two groups in waxy wheat, but were divided into three groups in non-waxy wheat. Compared with non-waxy wheat starch, waxy wheat starch had higher swelling power, gelatinization temperatures (To, Tp, Tc), and relative degree of crystallinity. They showed similar ordered structures on external regions of starch granules. Additionally, waxy wheat starch had a higher proportion of double-helical components and a lower proportion of single-helical components than non-waxy wheat starch. Based on the previous results, it was concluded: (1) waxy wheat and non-waxy wheat not only differed in starch granule development, but also in physicochemical properties of starches; (2) waxy wheat had more potential value for producing traditional products than non-waxy wheat.