Available lysine in dried milk after processing

Raw milk, dried milk and stored dried milk (6 and 18 months) were analyzed for total lysine and available lysine. Total lysine and available lysine content of the samples ranged between 7.92-9.02 g/16 g N and 6.20-8.76 g/16 g N, respectively. Available lysine content of the raw milk decreased 14.27% by drying process. Structural changes in dried milk due to crystallisation of lactose might have increased the Maillard reaction causing losses in available lysine of dried milk accounting to 15.45% after 6 months and to 17.44% after 18 months of storage at room temperature (20-30 degrees C).