Generation of tripalmitin microparticles from its melts was investigated by using both supercritical CO2 and supercritical N2.The effects of various operating conditions,such as the pre-expansion pressure,pre-expansion temperature,and nozzle size on the particle morphology,particle size and particle size distribution(PSD) were investigated.Results showed that microspheres were obtained from the N2-assisted process,the particle size decreased and PSD narrowed with the increasing of the pre-expansion pressure,nozzle size showed no obvious effect on the microparticles,and pre-expansion temperature should be less than 72 ℃ to obtain solid particles.From the CO2-assited process,spherical,lamellate and needle-like particles were obtained,the particle size decreased,PSD narrowed with the increasing of the pre-expansion pressure,nozzle size showed no obvious effect on the particles and the pre-expansion temperature slightly increased the average size of particles.Particles' PSD from supercritical CO2 was close to that from supercritical N2.