Abstract:

【Objective】 In this study, the influence of different detection methods on the determination results of maize amylose and amylopectin content was discussed to provide a theoretical basis for the detection of maize starch content. 【Methods】 The contents of amylose and amylopectin in different maize were determined by dual wavelength spectrophotometer. The reference wavelength, absorbance and absorption spectrum of starch solution in different maize were compared, and the starch granule structure was observed by scanning electron microscope to study the factors affecting the determination of corn starch content. 【Results】 The amylose content in high amylose corn, normal corn and waxy corn is 64.8%, 25% and 1.9% respectively, and the amylopectin content is 32.3%, 75.6% and 97.1% respectively. Under acetic acid and hydrochloric acid treatments, the pH values of the three corn starch solutions decreased, and acetic acid had the greatest effect on the pH values of high amylose corn starch solutions. 【Conclusion】 Under hydrochloric acid treatment, the absorbance values and absorption peaks of the three starch solutions were higher than those of acetic acid treatment, and the absorbance and absorption spectra of amylose were higher than those of amylopectin. Normal corn starch granules are swollen, uneven and irregular in shape. Although the structure of high amylose corn starch granules has changed, it is not as violent as normal corn. Amylose aqueous solution is not stable as amylopectin aqueous solution.

Key words: starch solution; pH value; absorbance; aspiration spectrum; crystal structure; starch solution stability

摘要：

【目的】 研究不同检测方法对玉米直链淀粉和支链淀粉含量测定结果的影响,为玉米淀粉含量检测提供理论依据。【方法】 采用双波长分光光度计测定不同玉米中直链淀粉、支链淀粉含量,比较不同玉米中淀粉溶液参比波长、吸光度和吸光谱,并利用扫描电镜观察淀粉颗粒结构,研究影响玉米淀粉含量测定的因素。【结果】 高直链玉米、普通玉米和糯玉米中直链淀粉淀粉含量分别为64.8%、25%和1.9%,支链淀粉含量分别为32.3%、75.6%和97.1%。乙酸和盐酸处理后,3种玉米淀粉溶液pH值均降低,其中乙酸对高直链玉米淀粉溶液pH值影响最大。【结论】 盐酸处理后3种淀粉溶液吸光度值以及吸收峰值均高于乙酸处理的吸光度值,并且直链淀粉吸光度及吸光谱高于支链淀粉。普通玉米淀粉颗粒膨大,表面凹凸不平,呈不规则形状,高直链玉米淀粉颗粒结构改变虽有变化,但没有普通玉米剧烈。直链淀粉水溶液没有支链淀粉水溶液稳定。

关键词: 淀粉溶液, pH值, 吸光度, 吸光谱, 晶体结构, 淀粉溶液稳定性