Droplet size and size distribution changes at homogenization of paraffin oil emulsions, stabilized by different concentrations of various emulsifiers, were investigated. During homogenization, samples were taken from emulsions and the most frequently occuring diameter, mean droplet diameter and standard deviation (distribution width) were determined. Mathematical relations describing changes of mean diameter and distribution width, as a function of the homogenization period and emulsifier concentration, were derived and applied to the experimental data. Emulsifier efficiencies and capabilities were characterized by physical constants and graphically. Optimal homogenization time interval, optimal emulsifier concentrations and corresponding droplet size distribution parameters were computed.

Thixotropic behaviour of starch, gelatin and mixed starch/gelatin gels was investigated by different rheological methods by means of the rotational viscosimeter with coaxial cylinders. Influence of different factors (gel composition, preparation temperature, gel age, homogenization and viscosimeter rotor acceleration) on the coefficients of thixotropy and parameters of the flow equation was considered. The recovery of destructed gels was followed by Doherty‐Hurd method, but also a modified method was developed and applied for determination of some specificities in the rheological behaviour of starch and gelatin gels.

No abstract

No abstract

No abstract