3，5-二硝基水杨酸法测定蔗汁中还原糖含量的研究

Determination of reducing sugar content in sugar juice using 3,5 - dinitrosalicylic acid method

采用3，5-二硝基水杨酸法（DNS）测定蔗汁的还原糖含量。探讨了测量波长、DNS试剂用量、加热时间、放置时间对测定结果的影响。与目前分析所用的兰-艾农法、奥夫奈尔法比较，该方法操作简便，准确性较高，其线性方程为：Y=14．778x-0．6262，R2=0．9994，检出限为0．005mg／mL，加标回收率为99％～103％。用本法测定各种蔗汁的还原糖含量，获得满意的结果。

In this paper, 3, 5 - dinitrosalicylic acid method （DNS） was used for determination of reducing sugar content on different cane juices. The factors of determination to the results was explored, such as wavelength, reagent dosage , storage time, heating time. This method overcome the shortcomings of the Lane -Eynon Law and the Ofner Law which are currently used in sugar mill. The method was higher accuracy, the regression equation was as follow： y = 14.778x -0. 6262, R2=0. 9994, recoveries were in the range of 99% to 103%. This method has been applied to cane juices with satisfactory results.