Spray drying can be used to form crystalline amino acid particles of specific size and morphology by adjusting the process conditions. Combined with post-drying humidity treatment, porous and spherical alpha-glycine particles with "coral-like" morphology were produced by spray drying. Glycine solutions of 8 wt.% and 18 wt.% were spray dried at inlet temperatures between 105 degrees C and 185 degrees C using a microfluidic jet spray dryer. The inlet drying temperatures had no significant effect on the polymorphic forms of glycine, but significantly affected their morphology in terms of surface roughness and internal structure. Spray drying provides an easy fabrication approach of spherical alpha-glycine particles of the particle size in the range of 70-100 mu m with less separation, which is a significant advantage over the multiple-step cooling or evaporation processes. (C) 2015 Elsevier B.V. All rights reserved.