Food Hydrocolloids 10 : 63-67 (1996)
Improved Emulsifying Properties of Beta-Lactoglobulin by Conjugating with Carboxymethyl Dextran
K. Nagasawa, K. Takahashi and M. Hattori
Department ofApplied Biological Science,
Faculty of Agriculture,
Tokyo University of Agriculture and Technology
Tokyo 183, Japan
Bovine beta-lactoglobulin (BLG)-carboxymethyl dextran (CMD) conjugates could be prepared by using water-soluble carbodiimide. Two BLG-CMD conjugates were obtained, which maintained retinol-binding activity as strong as that of native BLG and had good emulsifying ability at neutral pH, as shown in previous report (Hattori, M. et al., 1994). The emulsifying properties of these BLG-CMD conjugates were investigated under various conditions by evaluating the stability of oil/water(O/W) type emulsions prepared with oleic acid and BLG-CMD conjugates. By conjugating with CMD, the emulsifying ability of BLG was greatly enhanced in the acidic pH range in the presence of NaCl below 0.2 M. After heating at constant temperature (40-80 degree C) for 10 min, the emulsifying ability of the BLG-CMD conjugates was higher than that of BLG under all heating conditions. BLG-CMD conjugates are thought to be valuable as an O/W emulsifiers.