A new high-pressure micronisation process for the gentle processing of high molecular mass gelatine

This article introduces a new high-pressure process for the gentle drying, micronisation and formulation of high molecular mass gelatine. Spray drying of gelatine solutions is a well-established process for very low molecular weight gelatine, aqueous solutions containing low gelatine concentrations or gelatine solutions containing viscosity reducing additives. In the introduced process, supercritical CO2 was applied to micronised aqueous gelatine solutions and was then expanded from high pressure into a spraying chamber to remove the water content by extraction and evaporation under moderate conditions. The resulting product was analysed using common powder analysis methods. Aqueous gelatine solutions with a dry mass content of up to 50 wt.% with a molecular mass of 156,000 g mol−1 were pulverised and dried with this process, with only limited degradation by hydrolysis during processing.

► Aqueous gelatine solutions, mixed with scCO2, were atomised through a nozzle.
► Dry mass contents can be up to 60 wt.%.
► The result is a dry powder.
► Processing lowers the molecular weight only slightly.