Search

Starch is the major component in the wheat kernel, which is mainly composed of amylose and amylopectin. The wheat without amylose in its endosperm was called “waxy wheat”. Waxy wheat can be used to adjust the amylose content and improve the wheat-based food quality by adding to non-waxy wheat flour. In order to investigate the effect of waxy wheat flour on the quality of fresh and stale bread, waxy wheat flour was added into the flour of Canadian Spring Wheat 2 at 0.0, 5.0, 10.0, 15.0, 20.0, 25.0, 30.0, and 35.0% to make breads. The physicochemical properties were adjusted to suitability by adding Yangmai 158 flour, and breads were evaluated for sensory quality, crumb firmness, loaf volume and weight loss over a period of 0, 2, 4, and 6 days. The result showed that the best total score of fresh bread was 82.9 by adding waxy flour at 7.0%, though no significant difference was found among blends with 0.0-15.0% of waxy flour. Breads with the addition of 22.0% waxy flour had lower firmness, and decreasing loss of weight. Waxy wheat flour blend at 15.0% was optimal in retarding staling without significant decreasing fresh bread quality in comparison to the control.

In order to study the influencing factors on Raman spectroscopy, we research a series of comparative Raman spectroscopy of multi-walled carbon nanotubes (MWCNT) with different tube diameter and length. The results suggest that the G peak and D peak of MWCNT are all red-shifted as compared to that of polycrystalline graphite; In the same conditions, the peak intensity (G peak and D peak) is directly proportional to the diameter of the MWCNT, and inversely proportional to the length of the MWCNT; G peak frequency shift is closely related to the MWCNT diameter and length, which are inversely proportional to the diameter (with identical results of the single-walled carbon nanotube radial breathing modes) and direct proportional to the length. While, the influences of the diameter and length on D peak frequency shift are weak, and future analysis for the reason of this kind of phenomenon is as follows. Subsequently, we investigated the relation between D peak frequency shift and MWCNT aspect ratio, the relationship between G peak frequency shift and aspect ratio is nearly linear increase. Using the same analysis method, we plotted the different graphs of G peak and D peak intensity vs the aspect ratio of MWCNT, respectively. As the expected, the linear degression relation are existent in the two relationships.

为明确不同 Wx 基因对小麦直链淀粉含量的影响以及筛选面条品质优异的基因型，以糯小麦品系Caiwx (aabbdd)为3个 Wx 基因隐性突变供体亲本，以扬麦01-2 (AABBDD)为轮回亲本，利用连续回交结合花粉碘染、STS标记和同工酶标记检测方法，创制了8种 Wx 基因纯合基因型的近等基因系，其基因型分别为AABBDD、AABBdd、AAbbDD、AAbbdd、aaBBDD、aaBBdd、aabbDD和aabbdd。利用这些基因型探讨了不同 Wx 基因对直链淀粉含量及面条感官品质的影响。结果表明，各系的直链淀粉含量为0.9%~24.8%，系间差异显著；糯小麦型(aabbdd)直链淀粉含量最低，双缺失型和单缺失型其次，双缺失型中aaBBdd型含量最高，单缺失型中AAbbDD型含量最低，表明 Wx - B1 对直链淀粉的合成作用最大。糯小麦型面条的色泽、表观、软硬度、黏性、韧性得分以及总分显著低于其他类型及轮回亲本扬麦01-2；单缺失型面条的色泽、表观得分、总分显著高于轮回亲本扬麦01-2，其中aaBBDD型面条品质表现突出，与市售优质面条粉“雪花粉”制作的面条得分相当，而其他7种基因型及轮回亲本扬麦01-2的面条评分均显著低于雪花粉。说明可以通过遗传操作 Wx 基因培育优质面条小麦品种。