During the manufacture of MPCs the protein content of skim milk is concentrated and the lactose is filtered out using membrane filtration. For example, NFDM contains about 34% to 36% protein and 52% lactose, whereas MPC42 contains 42% protein and 46% lactose and MPC80 contains 80% protein and 5% to 6% lactose (Smith 2014). MPCs with even higher protein content are also available, and are generally known as MPIs with more than 90% protein (generally in the range of 90% to 91% protein; Smith 2014).