Comparison of the Gelation Properties of .beta.-Lactoglobulin Genetic Variants A and B

The gelation of β-lactoglobulin genetic variants A and B (β-Lg A and β-L8 B) was examined with 7% protein solutions at pH 7. Both variants formed viscoelastic solid gels exhibiting low phase angles (<8 o ) and dramatically increasing storage moduli during the cooling period as measured by small-strain dynamic rheology. However, β-Lg A had a lower gelation point (72.3 o C) and a higher initial gelling rate (15.4 Pa/min) than β-Lg B (7.6 min at 80 o C and 2.9 Pa/min, respectively). Furthermore, the β-Lg A gel had different viscoelastic properties than the B variant gel, as indicated by a shorter relaxation time (60 s) than that of the B variant (156 s)