I would use a coffee bean grinder then a sieve screen to select the particle size. For a more selective particle sizing method use an ultacentrifuge.

Please add some cryoprotectant e.g.mannitol(5%w/v) in your preparation and lyophilize it.Your problem would be solved.

these structures which you get after lyophilisation reflect the structures which your colloidal system has in the liquid form. I would assume already simple grinding would destroy them, but I personally would feel sad, because I love these structures.

Did you take optical microscope and SEM pictures of them? I would be interested to see them:

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For more background, you may want to look at

https://www.researchgate.net/publication/245535674_Dissipative_Structures_in_Colloidal_Systems?ev=srch_pub

https://www.researchgate.net/publication/243342949_Frozen_dissipative_structures_in_heterogeneous_polymer_systems_Critical_shear_rate__The_instability_reason_for_the_creation_of_dispersion_structures_in_polymers?ev=prf_pub

https://www.researchgate.net/publication/233979584_Dispersion_hypothesis_and_non-equilibrium_thermodynamics_key_elements_for_a_material_science_of_conductive_polymers._A_key_to_understanding_polymer_blends_or_other_multiphase_polymer_systems?ev=prf_pub

(SEM on page 135, but more info on this article!)

Article Dissipative Structures in Colloidal Systems

Article Frozen dissipative structures in heterogeneous polymer syste...

Article Dispersion hypothesis and non-equilibrium thermodynamics: ke...

Sandip Pal, I would be interested in the results of your experiments.

Did you take optical microscope and SEM pictures of the lyophilized powder? I would be interested to see them:

[email protected]