水分调控对两种筋力型小麦品种籽粒淀粉糊化特性的影响

在池栽、防雨条件下，研究了不同灌水对两种筋力型小麦品种淀粉糊化特性的影响。结果表明，两种筋力型品种间淀粉粘度参数差异达0．01显著水平，强筋型品种豫麦34稀懈值、糊化温度低于弱筋型品种豫麦50，而最终粘度、反弹值、高峰粘度和低谷粘度大于豫麦50。水分调控对两种筋力型品种淀粉糊化特性有显著的影响，豫麦50主要粘度参数以灌4水处理和抽穗期灌1水处理较好，灌拔节1水处理较差；而豫麦34以灌1水处理较好，灌4水处理较差，其中拔节期灌1水与抽穗期灌1水差异不显著。分析两品种粘度参数之间的关系，豫麦50主要粘度参数间达显著相关水平，而豫麦34多数粘度参数间相关不显著，在栽培措施上豫麦50比豫麦34具有同步提高淀粉品质的可能性。     

施氮量对不同品质类型小麦子粒蛋白质组分含量及加工品质的影响

选用强筋小麦济麦20、中筋小麦泰山23和弱筋小麦宁麦9号,利用反相高效液湘色谱（RP-HPLC）方法测定了施氮量对不同品质类型小麦子粒蛋白质组分含量和高分子量谷蛋白亚基（HMW-GS）、低分子量谷蛋白亚基（LMW-GS）含量的影响,并分析其与子粒加工品质的关系。结果表明,随施氮量增加,强筋小麦济麦20和中筋小麦泰山23的子粒蛋白质含量及各组分含量均呈先增加后降低的趋势,施氮量为N 240 kg/hm2时,蛋白质各组分含量较高,加工品质较好; 过量施氮抑制了HMW-GS合成,这是过量施氮导致强筋和中筋小麦子粒蛋白质品质变劣的原因之一。随施氮量增加,弱筋小麦宁麦9号子粒的蛋白质各组分含量显著增加,加工品质变劣。增施氮肥,3个品种的谷蛋白和醇溶蛋白含量的增加幅度显著高于清蛋白+球蛋白含量,这是施氮改善强筋和中筋小麦子粒加工品质的主要原因。济麦20和泰山23两品种的总蛋白质含量及醇溶蛋白含量无显著差异,但强筋小麦济麦20的谷蛋白含量、贮藏蛋白、HMW-GS、LMW-GS、谷蛋白大聚合体（GMP）含量及谷蛋白与醇溶蛋白含量的比值（Glu/Gli）和HMW-GS与LMW-GS含量的比值（HMW/LMW）高于中筋小麦泰山23,这是强筋小麦济麦20加工品质形成及其面团形成时间和稳定时间显著高于泰山23的重要原因。     

氮肥运筹比例对稻田套播强筋小麦子粒品质和产量的影响

为探索稻田套播强筋小麦实现优质高产的适宜氮肥运筹比例,选用强筋小麦品种烟农19,于2004至2006年在江苏淮北的铜山和赣榆两地研究了5种氮肥运筹比例(基肥∶分蘖肥∶拔节肥∶孕穗肥分别为6∶1∶3∶0、5∶1∶4∶0、5∶1∶2∶2、3∶3∶2∶2和3∶3∶1∶3)对稻茬强筋小麦子粒产量和营养品质与加工品质的影响。结果表明,随拔节肥和孕穗肥施氮比例上升:1)子粒蛋白质和湿面筋含量上升,但对清蛋白与球蛋白含量影响较小,对醇溶蛋白、谷蛋白含量影响较大;2)子粒淀粉含量下降,面粉峰值粘度、低谷粘度、稀解值和最终粘度呈先下降后又上升的趋势;3)面团形成时间和稳定时间增加;4)子粒产量逐渐升高,但后期施肥比例过高,产量有所下降。因此,稻田套播强筋小麦优质高产栽培氮肥运筹宜采用基肥∶分蘖肥∶拔节肥∶孕穗肥为3∶3∶2∶2的比例。     

施氮量对不同品质类型小麦产量和加工品质的影响

为了明确施氮量与不同品质类型小麦的产量和品质的关系,选用强筋小麦济麦20、 皖麦38和中筋小麦京冬8、 中麦8共2种品质类型4个小麦品种,研究了施氮量对其产量性状和加工品质的影响。结果表明,在施氮量N 0-360 kg/hm2的范围内,增加氮肥用量可以有效缓解叶绿素降解,抑制旗叶全氮含量降低,缓解叶片衰老,延长旗叶功能期; 强筋小麦品种比中筋小麦品种旗叶叶绿素含量和氮素含量下降缓慢。子粒产量和蛋白质产量随施氮量的增加逐渐提高,施氮N 270 kg/hm2时达到最大值,增加到360 kg/hm2时子粒产量和蛋白质产量均开始下降。强筋小麦蛋白质产量和子粒产量高,中筋小麦穗数、 穗粒数多,千粒重高。施氮有利于子粒出粉率、 硬度、 蛋白质含量和沉降值的提高。施氮N 180 kg/hm2时可以显著延长面团形成时间和稳定时间,降低吸水率,面包总体评分最高。强筋小麦硬度大,蛋白质含量、 出粉率和沉降值高,面团形成时间和稳定时间长,面包体积大、 评分高。     

水氮运筹对两种穗型冬小麦品种淀粉糊化特性的影响

在大田条件下,对两种穗型冬小麦品种的淀粉糊化特性及其水氮调控效应进行了研究。结果表明:两种穗型品种的高峰粘度与其它参数的相关性最高,尤其是与低谷粘度、最终粘度的相关系数均达0.93以上,可作为衡量淀粉糊化特性的一个重要指标。两品种比较,豫麦66除稀懈值高于豫麦49外,其它指标均低于豫麦49,说明豫麦49淀粉糊化特性好。水氮措施对两品种淀粉糊化特性均具有重要影响。豫麦49各粘度参数的变异系数较高,这有利于栽培调控,改善淀粉品质。就水氮运筹的整体调控效应而言,豫麦66以施氮素300 kg/hm2较好,灌水以灌一水处理较为适宜,而豫麦49氮素运用以150 kg/hm2最好,灌水以灌两水处理比较有效。水氮间存在交互效应,灌水条件不同,所要求的适宜施氮量就存在差异,品种间这种差异表现更为明显。     

施磷对小麦旗叶氮代谢关键酶活性和子粒蛋白质含量的影响

在田间试验条件下,以强筋品种济麦20和弱筋品种山农1391为材料,研究了不同施磷水平对2类型品种小麦旗叶氮代谢关键酶活性和子粒蛋白质积累的效应。结果表明,在P2O5 0～135 kg /hm2范围内,施磷明显提高济麦20灌浆前期旗叶硝酸还原酶（NR）和谷氨酰胺合成酶（GS）活性;但却降低山农1391旗叶NR、GS活性。强筋品种济麦20在灌浆中、后期旗叶内肽酶（EP）、羧肽酶（CP）活性和蛋白质含量因施磷而提高;而弱筋品种山农1391的EP、CP活性和子粒蛋白质含量则降低。施磷使济麦20子粒清蛋白、醇溶蛋白和谷蛋白的含量提高,球蛋白含量有所降低;但弱筋品种山农1391子粒球蛋白、醇溶蛋白和谷蛋白的含量因施磷而降低,清蛋白含量未见显著变化。说明小麦施磷应考虑不同品质类型品种氮代谢及子粒蛋白质含量对施磷的反应。     

不同类型专用小麦氮素吸收积累差异研究

2000至2002年在田间条件下,研究3个不同类型专用小麦品种(强筋小麦皖麦38、中筋小麦扬麦10号和弱筋小麦宁麦9号)氮素吸收积累差异。试验结果表明,成熟期植株含氮率与子粒含氮率均以强筋小麦皖麦38最高,弱筋小麦宁麦9号最低。成熟期植株氮积累量为皖麦38最高,子粒氮积累量为扬麦10号最高。不同品种不同生育阶段吸收的氮素占一生总氮量的比例不同,弱筋小麦宁麦9号在出苗拔节期氮积累量占整个生育期中的比例较其它品种高,而强筋小麦皖麦38在开花成熟期较其它两个品种高。结果还表明,不同类型专用小麦品种每生产百公斤子粒所需吸收的氮量也不相同。     

氮磷互作对弱筋小麦氮素利用与籽粒淀粉品质的影响

为了解氮磷对弱筋小麦品种氮素利用效率及籽粒淀粉品质的影响,以宁麦13为材料,在施氮120kg/hm~2(N1)、180 kg/hm~2(N2)水平下,分别设置3个磷素水平(施P_2O_5水平为P1:60 kg/hm~2,P2:120 kg/hm~2,P3:180 kg/hm~2),分析氮磷素对弱筋小麦植株氮素吸收利用、籽粒淀粉粒度分布与黏度参数的影响。结果表明:增施磷肥使开花期植株单株氮素积累量和成熟期植株与籽粒氮素积累量显著增加。在N1水平下花前营养器官氮素单株转运量无显著差异,N2水平下随施磷增加花前营养器官氮素单株积累量先增加后下降,且N2P2和N2P3无显著差异。N2水平下弱筋小麦花前营养器官氮素向籽粒转运率、贡献率显著低于N1水平;增施磷肥不利于花前营养器官氮素向籽粒转运率、贡献率的提高。N1水平下弱筋小麦氮肥生产效率、氮素利用效率高于N2水平;增施磷肥有利于氮肥生产效率的提高,但使氮素利用效率下降。施磷影响弱筋小麦淀粉粒度分布,增施磷肥提高了小麦A型淀粉粒体积、表面积百分比,降低B型淀粉粒体积、表面积百分比;增加了淀粉峰值黏度、谷值黏度、最终黏度、崩解值和回升值等参数。本试验条件下增加施磷量显著提高了弱筋小麦植株与籽粒氮素积累量,显著增加植株在开花后营养器官与籽粒的即时氮素积累量,进而提高氮肥生产效率;显著提高A型淀粉粒体积和表面积百分比,进而提高淀粉黏度参数。     

追氮量对不同品质类型小麦产量和品质的调节效应

以不同品质类型的4个小麦品种为试验材料,采用二因素随机区组设计,研究了品种和氮肥运筹对产量和品质的影响。结果表明,在底肥相同的条件下,在一定范围内增加追施氮肥,产量显著提高。增施氮肥可显著提高各品种子粒蛋白质含量。除吸水率外,不同品种各项品质指标均随施氮量增加而提高,处理间差异显著。B2和B3(增加追施氮肥)的拉伸度、拉伸面积、面包体积和面包评分均显著优于B1(未追施氮肥)。子粒蛋白质含量与其它14项品质指标呈正相关。吸水率、沉降值、形成时间、稳定时间、拉伸阻力、拉伸比值、最大拉伸阻力、最大拉伸比值、拉伸面积、面包体积、面包评分等11项指标间存在显著或极显著的正相关关系。试验结果表明,强筋小麦品种并非各项品质性状均优于中筋小麦品种。     

施氮水平对优质小麦旗叶光合特性和子粒生长发育的影响

通过对两个优质小麦品种不同施氮量的比较试验,研究了氮素水平对优质小麦生育后期旗叶光合特性和子粒生长发育特点及产量的影响。结果表明,强筋小麦8901施氮量在N.1203～60.kg/hm2范围内,旗叶光合速率、蔗糖含量、淀粉含量和粒重都表现为随施氮量的增加而降低。弱筋小麦SN1391施氮量在N.1202～40.kg/hm2的范围内,上述指标和施氮量呈正相关,但当氮肥用量增加到360.kg/hm2时,则迅速降低。研究还表明,两优质小麦都表现为随施氮量的增加叶绿素含量提高,但过高氮肥用量又使其降低;旗叶叶绿素含量和其光合速率之间相关不显著;旗叶光合速率和粒重之间存在正相关。     

Bread Quality of Spelt Wheat and Its Starch

Flours from five spelt cultivars grown over three years were evaluated as to their breadbaking quality and isolated starch properties. The starch properties included amylose contents, gelatinization temperatures (differential scanning calorimetry), granule size distributions, and pasting properties. Milled flour showed highly variable protein content and was higher than hard winter wheat, with short dough‐mix times indicating weak gluten. High protein cultivars gave good crumb scores, some of which surpassed the HRW baking control. Loaf volume was correlated to protein and all spelt cultivars were at least 9–51% lower than the HRW control. Isolated starch properties revealed an increase in amylose in the spelt starches of 2–21% over the hard red winter wheat (HRW) control. Negative correlations were observed for the large A‐type granules to bread crumb score, amylose level, and final pasting viscosity for cultivars grown in year 1999 and to pasting temperature in 1998 samples. Positive correlations were found for the small B‐ and C‐type granules relative to crumb score, loaf volume, amylose, and RVA final pasting viscosity for cultivars grown in 1999, and to RVA pasting temperature for samples grown in 1998. The environmental impact on spelt properties seemed to have a greater effect than genetic control.     

Increase in Apparent Amylose Content and Change in Starch Pasting Properties at Cool Growth Temperatures in Mutant Wheat

Some mutant wheat lines with low‐amylose content were grown in a field and greenhouse (15 or 20°C) to compare apparent amylose content and starch pasting properties. The apparent amylose content of flour and starch increased and starch pasting parameters as measured by a Rapid Visco Analyser (RVA) changed in the greenhouse (at cool temperatures) during seed maturation. Densitometric analysis of the protein band separated by electrophoresis suggested that the increase in amylose content by cool temperature was related to the amount of Wx‐D1 protein. This data suggests that the Wx‐D1 gene was responsible for these changes. In wheat starch from Tanikei A6099 and Tanikei A6598 at 15°C, the value of final viscosity and total setback was higher than that from the field. In wheat starch from Tanikei A6599‐4 (waxy mutant with stable hot paste viscosity), the peak viscosity temperature was higher and time maintained >80% of the peak was shorter at 15°C than that from the field. Genetic analysis using doubled‐haploid (DH) lines from a combination of Tanikei A6599‐4 and Kanto 118 (low‐amylose line) showed that apparent amylose content increased and the starch pasting curve and properties changed in waxy progenies similar to Tanikei A6599‐4.     

Factors Governing Pasting Properties of Waxy Wheat Flours

Waxy wheat (Triticum aestivum L.) contains endosperm starch lacking in amylose. To realize the full potential of waxy wheat, the pasting properties of hard waxy wheat flours as well as factors governing the pasting properties were investigated and compared with normal and partial waxy wheat flours. Starches isolated from six hard waxy wheat flours had similar pasting properties, yet their corresponding flours had very different pasting properties. The differences in pasting properties were narrowed after endogenous α‐amylase activity in waxy wheat flours was inhibited by silver nitrate. Upon treatment with protease, the extent of protein digestibility influenced the viscosity profile in waxy wheat flours. Waxy wheat starch granules swelled extensively when heated in water and exhibited a high peak viscosity, but they fragmented at high temperatures, resulting in more rapid breakdown in viscosity. The extensively swelled and fragmented waxy wheat starch granules were more susceptible to α‐amylase degradation than normal wheat starch. A combination of endogenous α‐amylase activity and protein matrix contributed to a large variation in pasting properties of waxy wheat flours.     

Genetic variation in the physical properties of sweet potato starch.

Sweet potato starch, prepared from 44 genotypes adapted to Philippine conditions, showed wide variation and distinctly different pasting profiles in Rapid Visco-Analyzer (RVA) analysis at 11% and 7% starch concentration. At 11% starch concentration, the pasting profiles were type A, characterized by high to moderate peak with a major breakdown and low cold paste viscosity. At 7%, the pasting profile was generally type C, characterized by the absence of a distinct peak with none to very slight breakdown and high cold paste viscosity. However, differentiation among genotypes was better achieved from RVA pasting profiles at 11% starch concentration. Peak viscosity (PV) and hot paste viscosity (HPV) at 11% starch paste concentration had significant negative correlation with amylose content. PV, HPV, and setback ratio were significantly correlated to adhesiveness of the starch gel. Sweet potato starch generally had high swelling volume but low solubilities at 92.5 degrees C.     

Significance of Starch Properties and Quantity on Sponge Cake Volume

We evaluated the qualitative and quantitative effects of wheat starch on sponge cake (SC) baking quality. Twenty wheat flours, including soft white and club wheat of normal, partial waxy, and waxy endosperm, as well as hard wheat, were tested for amylose content, pasting properties, and SC baking quality. Starches isolated from wheat flours of normal, single‐null partial waxy, double‐null partial waxy, and waxy endosperm were also tested for pasting properties and baked into SC. Double‐null partial waxy and waxy wheat flours produced SC with volume of 828–895 mL, whereas volume of SC baked from normal and single‐null partial waxy wheat flours ranged from 1,093 to 1,335 mL. The amylose content of soft white and club wheat flour was positively related to the volume of SC (r = 0.790, P < 0.001). Pasting temperature, peak viscosity, final viscosity, breakdown, and setback also showed significant relationships with SC volume. Normal and waxy starch blends having amylose contents of 25, 20, 15, and 10% produced SCs with volume of 1,570, 1,435, 1,385, and 1,185 mL, respectively. At least 70 g of starch or at least 75% starch in 100 g of starch–gluten blend in replacement of 100 g of wheat flour in the SC baking formula was needed to produce SC having the maximum volume potential. Starch properties including amylose content and pasting properties as well as proportion of starch evidently play significant roles in SC baking quality of wheat flour.     

Amylose-lipid complexes as controlled lipid release agents during starch gelatinization and pasting

The effect of amylose-lipid (AM-L) complexes consisting of amylose populations with different peak degrees of polymerization (DP) and complexed with glyceryl monostearate (GMS) or docosanoic acid (C22) on the pasting properties of wheat and rice starches was evaluated with a rapid visco analyzer (RVA). AM-L complexes were formed by both (i) addition of lipids to amylose fractions with peak DP 20, 60, 400, or 950 at 60 degrees C or (ii) potato phosphorylase-catalyzed amylose synthesis in the presence of lipids. All AM-L complexes affected pasting properties in line with their dissociation characteristics. AM-L complexes therefore have potential as "controlled lipid release agents" with effects markedly different from those observable with emulsifier addition in starch pasting. More in particular, short chain AM-L complexes resulted in a starch pasting behavior comparable to that of cross-linked starch, as evidenced by reduced granule swelling, good viscosity stability in conditions of high temperature and shear, and a stable cold paste viscosity.     

Octenyl succinic anhydride modified early indica rice starches differing in amylose content

Seven early indica rice starches with different amylose contents were modified by octenyl succinic anhydride (OSA) in aqueous suspension systems to evaluate the effect of amylose contents on starch esterification. The crystalline structure and pasting properties of starches were investigated using X-ray diffraction and a Rapid Visco Analyzer (RVA). The results indicated that the amylose content had a positive impact on the OSA modification. As the amylose content increased from 0 to 39.6%, the degree of substitution increased from 0.024 to 0.030 and the reaction efficiency increased from 62.8 to 77.5%. X-ray diffraction scans confirmed that the amylose was mainly present in the amorphous domain of the granule and was highly substituted after the OSA treatment. The RVA profiles demonstrated that the OSA starches had higher viscosities than their native counterparts. Moreover, negative correlations were observed between the amylose content and the major RVA parameters (e.g., peak viscosity, hot paste viscosity, cool paste viscosity, and breakdown viscosity).     

Physicochemical Properties and In Vitro Starch Digestibility of Cooked Rice from Commercially Available Cultivars in Canada

The influence of amylose content, cooking, and storage on starch structure, thermal behaviors, pasting properties, and rapidly digestible starch (RDS), slowly digestible starch (SDS), and resistant starch (RS) in different commercial rice cultivars was investigated. Long grain rice with high‐amylose content had a higher gelatinization temperature and a lower gelatinization enthalpy than the other rice cultivars with intermediate amylose content (Arborio and Calrose) and waxy type (glutinous). The intensity ratio of 1047/1022 cm^–1 determined by Fourier Transform Infrared (FT‐IR), which indicated the ordered structure in starch granules, was the highest in glutinous and the lowest in long grain. Results from Rapid ViscoAnalyser (RVA) showed that the rice cultivar with higher amylose content had lower peak viscosity and breakdown, but higher pasting temperature, setback, and final viscosity. The RDS content was 28.1, 38.6, 41.5, and 57.5% in long grain, Arborio, Calrose, and glutinous rice, respectively, which was inversely related to amylose content. However, the SDS and RS contents were positively correlated with amylose content. During storage of cooked rice, long grain showed a continuous increase in pasting viscosity, while glutinous exhibited the sharp cold‐water swelling peak. The retrogradation rate was greater in rice cultivars with high amylose content. The ratio of 1047/1022 cm^–1 was substantially decreased by cooking and then increased during storage of cooked rice due to the crystalline structure, newly formed by retrogradation. Storage of cooked rice decreased RDS content and increased SDS content in all rice cultivars. However, no increase in RS content during storage was observed. The enthalpy for retrogradation and the intensity ratio 1047/1022 cm^–1 during storage were correlated negatively with RDS and positively with SDS (P ≤ 0.01).     

不同品种小麦粉的粉质特性对速冻熟制面条品质的影响

为研究不同品种小麦粉与速冻熟制面条质构特性之间的关系,选取30种小麦制粉,用FOSS定氮仪、快速黏度仪、粉质仪和拉伸仪等测定面粉品质指标,制作速冻熟制面条,用质构仪测定质构特性。采用描述性统计、主成分和聚类分析方法对30种小麦面粉和速冻熟制面条的质构关系进行了分析。结果表明:不同品种小麦粉的湿面筋、糊化温度、弱化度、粉质质量指数与硬度呈极显著相关(P0.01);蛋白质、湿面筋、总淀粉含量、最终黏度、回生值、糊化温度、粉质吸水率、粉质曲线稳定时间、面团形成时间、弱化度、粉质质量指数、拉伸曲线面积、拉伸阻力、最大拉伸阻力与剪切力呈极显著相关(P0.01);小麦粉的粉质特性,除衰减值、峰值时间和延伸度外,均与拉伸力呈极显著相关(P0.01)。根据方差贡献率提取出可以反映原变量84.023%信息的5个因子,因子1主要反映面粉的粉质拉伸特性,因子2反映小麦粉糊化特性,因子3反映蛋白质特性,因子4和因子5共同反映小麦粉的淀粉特性。这些性状在小麦粉的评价方面起着重要作用,在加工中要注重对它们的选择。聚类分析将30种小麦粉分为4类,结果表明,不能仅凭小麦粉的指标数据和质构数据来选择制作速冻熟制面条的原料,还需考虑到感官评价的影响。该结论可为小麦粉在速冻熟制面条加工应用方面提供一定的理论参考。     

High temperature during grain fill alters the morphology of protein and starch deposits in the starchy endosperm cells of developing wheat (Triticum aestivum L.) grain

High temperature during grain fill reduces wheat yield and alters flour quality. Starchy endosperm cell morphology was investigated in wheat ( Triticum aestivum L. 'Butte 86') grain produced under a 24/17 or 37/28 °C day/night regimen imposed from anthesis to maturity to identify changes in cell structure related to the functional properties of flour. The duration of grain fill decreased substantially under the 37/28 °C regimen, but, like the 24/17 °C regimen, endosperm cells in the mature grain were packed with starch and protein. However, A-type starch granules increased in number, decreased in size, and exhibited pitting; B-type granules decreased in both number and size; and the protein matrix was proportionally greater in endosperm cells of grain produced under the 37/28 °C regimen. Such changes in starch granule number, size, and structure and in protein amount are known to contribute to variations in wheat flour quality.