Physicochemical and Structural Properties of Ultrafiltered Buffalo Milk and Milk Powder

¹ Dairy Technology Division, National Dairy Research Institute, Karnal 132001, India
² Dairy Science Department, South Dakota State University, Brookings 57007-0647

Buffalo skim milk containing 10.20% total solids (TS), 3.96% protein, and 5.22% lactose was ultrafiltered at 50°C to 23.50% TS and 16.44% protein. Contents of TS, fat, ash, and protein increased during UF, and lactose content decreased. The composition of permeate was influenced by the concentration factor during UF of milk; as the concentration factor increased, TS, protein, ash, and lactose content increased. The rejection coefficients after 77% weight reduction were 52.52% for TS, 94.95% for protein, 100% for fat, and 52.04% for ash. Rennet coagulation time decreased, and gel firmness increased after coagulation as the protein concentration of the milk increased. As examined by scanning electron microscopy, particles of buffalo skim milk powder had smooth surfaces, but most had dents of varying sizes. Particle sizes ranged from 2 to 55 µm in diameter.

Key Words: buffalo milk • rennet coagulation • microstructure

Submitted on February 2, 1996
Accepted on October 21, 1996