Kinetics of microstructure formation of high-pressure induced gel from a whey protein isolate

The kinetic process of pressure-induced gelation of whey protein isolate (WPI) solutions was studied using in situ light scattering. The relationship of the logarithm of scattered light intensity (I) versus time (t) was linear after the induced time and could be described by the Cahn-Hilliard linear theory. With increasing time, the scattered intensity deviated from the exponential relationship, and the time evolution of the scattered light intensity maximum Im and the corresponding wavenumber qm could be described in terms of the power-law relationship as Im∼fβ and qm∼f-α, respectively. These results indicated that phase separation occurred during the gelation of WPI solutions under high pressure.