Synergistic Interaction Between ß-Lactoglobulin and Bovine Serum Albumin in Heat-Induced Gelation

¹ Department of Applied Biochemistry, Yamaguchi University, Yamaguchi 753, Japan

Heat-induced gelation in a mixed system of ß-LG and BSA was studied. The hardness of the gels made with the mixture was affected significantly by the relative proportion of ß-LG and BSA; upon heating (30 min at 80°C), the mixture formed a harder gel at the mixing ratio of 1:1 (wt/wt). The 6% (wt/vol) mixed protein solution with the mixing ratio of 1:1 (wt/wt) formed a much harder gel than did the 6% ß-LG or 6% BSA gels, although neither ß-LG nor BSA was individually capable of gelation at its concentration in the mixture. The formation of soluble aggregates of ß-LG was facilitated by the coexistence of BSA. ß-Lactoglobulin and BSA interacted to form soluble aggregates through the thiol oxidation reaction during heating. Such interactions may cause the formation of the stronger, more stable gel matrix in a mixed system of ß-LG and BSA.

Key Words: whey proteins • thermal gelation

Submitted on July 20, 1993
Accepted on January 3, 1994