Casein was chemically modified with acetic, succinic, and maleic anhydride and changes in functional pro-perties were evaluated as affected by the degree of modification. Chemical modification resulted in casein with unique functional properties depending upon the type of anhydrid used and the degree of modification. It was possible to control heat coagulation, calcium precipitability, forming and emulsion capacity and stability. At pH 4.5 heat coagulation was 0% in the case 74.1% acetylated casein; on the contrary, succinylation and maleyation resulted in highly heat sensitive protein. Foaming properties were improved markedly by suc-cinylation and maleylation at pH 4.5. However, emulsifying properties were enhanced only by maleylation.