Induction times for onset of nucleation and nucleation rates were determined for amorphous sugar matrices made with sucrose and corn syrup held at temperatures between 60 and 110 degrees C. Induction times decreased and nucleation rates increased exponentially with increasing temperature. Both the classical nucleation rate equation and the Williams-Landel-Ferry (WLF) equation fit the data. Within the measurement variability, the type of corn syrup used did not cause a significant difference in either the induction times or nucleation rates. The kinetic barrier to nucleation was determined to be -76.7 to -127.2kJ/mole, which was 4-6 times higher than the activation energy for translational diffusivity of sucrose, suggesting that rotational diffusivity of sucrose and the interaction between corn syrup and sucrose also must play an important role in nucleation. (c) 2004 Elsevier Ltd. All rights reserved.