RATES OF CRYSTALLIZATION OF DRIED LACTOSE-SUCROSE MIXTURES

The isothermal crystallization kinetics of glassy lactose/sucrose mixt ures were studied at several storage temperatures (close to T-g and T- m). The kinetic parameters implicit in the Avrami equation were determ ined. Activation energies for transport (E(D)) and surface nucleation (W) were also found and correlated to the molar composition of the la ctose/sucrose mixtures. A monotonic increase in the half crystallizati on time (t(1/2)), Avrami index (n), % crystallization per day, activat ion energy for transport (E(D)) and surface nucleation energy (W) and a decrease in the crystallization velocity constants (K) were related to the increase in the lactose content of lactose/sucrose mixtures.