Comparative study on detection of lactose and sucrose in milk powder by Land-Eynon's method and high performance liquid chromatography with refractive index detector

Lactose and sucrosein the same brand of commercialdifferent ages milkpowder were assayed by Lan d-Eynon'smethod and high performance liquid chromatography with refractive index detector(HPLC-RID), and the differences of lactose and sucrose were analyzed, and the results of the two methods were compared. The res ults indicated that HPLC-RIDmethod was higher accuracy than that of Land-Eynon'smethod, the linear ran ges of sucrose and lactose were 2~12mg/mL, respectively.Their correlation coefficients were 0.9993 and 0. 9996, respectively.The relative standard deviationswere 2.53% and 3.81%, respectively. The average recove ry rates were 99.70% and 101.06%, respectively.The method had the advantages of accurate result, short analysis time and simple pretreatment, and was suitable for the rapid determination of sucrose and lactose