Size and shape characterization of conventionally and cryogenically groundturmeric (Curcuma domestica) particles

Turmeric (Curcuma domestica) powder was produced by conventional grinding a nd cryogenic grinding processes. The particle size and shape analyses of th e ground particles were carried out, utilizing the measurement system based on time-of-transition (TOT) principle. Weight mean diameter of cryo-ground particles are 50-mum finer than conventional-ground turmeric. The size dis tribution in both grinding methods followed the well known Rosin-Rammiler-B ennett (RRB) equation. The shape parameters of the particles of both grindi ng processes such as perimeter, shape factor (sphericity), average Ferret d iameter, aspect ratio were measured. The shape parameters of cryo-ground tu rmeric were in the lower range than those of conventionally ground turmeric . The analysis confirms the usefulness of cryo-ground process in producing finer particles for heat-sensitive materials such as turmeric. (C) 2001 Els evier Science B.V. All rights reserved.