Analysis of lactose in dairy products is described using an ACQUITY Arc System, an ACQUITY QDa Mass Detector, and an XBridge BEH Amide XP Column. The method limit of quantitation (LOQ) is estimated at 2.5 mg per 100 gram of final products with minimal interference from the matrix. The total run time of chromatography analysis is 25 min.
This lactose analysis method offers a sensitive, accurate, reliable, and robust way to determine lactose in dairy products. The estimated LOQ in the presence of sample matrix was about 2.5 mg/100 g, which is lower than the common threshold level for lactose-free products. This method has few co-eluting interferences. The total cycle time per injection is 25 minutes.
This method demonstrates that it is suitable for the lactose determination in dairy products, including low lactose and lactose-free dairy products.