The sad consequences, which surfaced in the 2nd half of 2008, of adding melamine to milk in order to artificially increase the apparent protein content, have highlighted the need for screening methods for the early detection of such adulteration of milk. Several analytical
methods (like ELISA & GCMS) for determining melamine in milk and milk products down to a few ppm or even ppb do exist, but these methods add significant cost and time if used on a routine basis. Achieving single digit ppm melamine detection limits with infrared analysis is impractical, but screening for melamine adulteration can be done effectively by using the Lactoscope FTIR at the same time as payment or incoming control tests are done, thus eliminating additional testing time and analytical costs. The addition of melamine to milk increases the apparent protein content by approximately four times the amount of melamine added when the protein content is estimated by either N-Kjeldahl or standard methods of infrared analysis. Given the limited solubility of melamine in water (3 g/kg or 3000 ppm) at ambient temperature, the apparent protein content of milk can only be raised about 35%, or 12g/l.