双波长法测定马铃薯淀粉中直链淀粉含量

Dual-wavelength Spectrophotometry Method for Measuring Amylose Contents of Potato Starch

使用双波长分光光度法测定马铃薯淀粉中直链淀粉的含量。根据双波长法的测定原理,确定马铃薯直链淀粉的测定波长和参比波长,直链淀粉分别为610和480 nm,支链淀粉分别为550和748 nm。试验结果表明,该测定方法标准曲线良好,即符合比耳定律。马铃薯直链淀粉的线性范围为20~80μg/m L,相关系数为r2=0.999 5,自制马铃薯淀粉中直链淀粉含量为0.069 9 mg/m L。样品的平均回收率为92.16%。该方法操作简单、测定高效准确,适用于工业上的批量检测。

Dual-wavelength spectrophotometry was applied to the determination of amylose content in potato starch. According to the principle of dual-wavelength method determination, determine the potato amylose measure wavelength and reference wavelength. Absorbencies at 610 and 480 nm were used for amylose content measurement, absorbencies at 550 and 748 nm were used for amylopectin content measurement. Beer＇s law was obeyed in concentration of 20-80 μg/mL for amylose, correlation index r2=0.999 5 and both the exactitude and accuracy were good. Homemade amylose content in potato starch was 0.069 9 mg/mL. The average recovery of samples was 92.16%. The method had the advantages of simple operation, high efficiency and accuracy, and the method was suitable for industrial batch test.