The change of pressure, temperature and phase during high-pressure carbon dioxide explosion process were investigated. Different initial temperature and pressure conditions were chosen, ranging from 25 to 65 degrees C and 500 to 3000 psi covering initial liquid, supercritical and gas phases. Under certain initial conditions with low temperature and high pressure, the depressurization process caused a phase change that increased the release time where the depressurization-time curves did not exponentially decrease. This explosion process was characterized based on total release time, rate of depressurization, and effect of phase change on the rate of depressurization. The temperature change associated with the change of pressure was also discussed. Canola flakes were exploded using chosen initial conditions. Oil extraction from canola flakes using supercritical carbon dioxide was improved after explosion treatment. Explosion at 35 degrees C and 3000 psi of initial condition resulted in the highest oil yield. (c) 2007 Elsevier B.V. All rights reserved.