1. A PROCESS FOR MAKING NONFAT DRY MILK COMRPISING SEQUENTIALLY HEATING SKIM MILK TO A TEMPERATURE AND FOR A TIME AT LEAST SUFFICIENT TO PASTEURIZE, CONCENTRATING THE PASTEURIZED LIQUID UP TO ABOUT 60 PERCENT TOTAL SOILDS, TEMPERING, SEEDING AND STIRRING THE CONCENTRATE UNDER CONDITIONS FAVORABLE TO LACTOSE CRYSTALLIZATION WHILE MAINTAINING THE FLOWABILITY THEREOF, THEN FORCING THE CONCENTATE UNDER A FIRST PRESSURE INTO A MIXING ZONE, INJECTING AN INNOCUOUS, RELATIVELY INSOLBLE COMPRESSED GAS AT A PRESSURE IN EXCESS OF SAID FIRST PRESSURE INTO THE CONCENTRATE IN THE MIXING ZONE TO PRODUCE IN SAID MIXING ZONE A GAS-CONCENTRATE MIXTURE IN WHICH THE GAS IS UNFORMLY DISPERSED, AND SPRAY DRYING IMMEDIATELY FOLLOWING THE INJECTION OF SAID IN-