EFFECTS OF CONTROLLED SULFITOLYSIS OF BOVINE SERUM-ALBUMIN ON DROPLET SIZE AND SURFACE-AREA OF EMULSIONS

Bovine serum albumin (BSA) was modified by oxidative sulfitolysis to cleave 10 and 17 disulfide bonds. The average droplet diameter and surface area of oil in water emulsions stabilized by native and modified BSA were determined with a computerized imaging system at three oil volume fractions (ø), namely, 0.22, 0.42, and 0.62. At ø = 0.22, no difference in the emulsifying properties of the proteins was observed. At ø = 0.42 and 0.62, the emulsions stabilized by modified BSA had smaller average diameters and greater surface areas than emulsions stabilized by native BSA. The emulsifying activity of BSA was enhanced by the increased flexibility and by exposure of hydrophobic segments of BSA resulting from the cleavage of disulfide bonds. © 1990, American Chemical Society. All rights reserved.