Modification of rheological, thermophysical, textural and some physical properties of corn starch by tribomechanical treatment

The aim of this research was to examine the effect of tribomechanical micronization and activation (TMA treatment) on rheological, thermophysical, textural and some physical properties of corn starch. In this work, samples were treated using laboratory equipment for tribomechanical micronization and activation (TMA equipment). Before and after the TMA treatment, analysis of the particle size and particle size distribution was carried out, in addition to micrography. The results showed that the TMA treatment causes a significant decrease in particle size, and change in particle size distribution of powdered corn starch. Micrography showed obvious impact of TMA treatment on structure and size of starch granules. TMA treatment caused disrupting of starch granules by mechanical forces and made the granule more permeable to water during the heating step. Because, statistically significant increase in solubility and swelling power was observed. TMA treatment caused significant lowering of the beginning gelatinization temperatures, which indicated an earlier state of granule swelling during heating. Also, TMA treatment has affected a significant increase of starch suspension viscosity. Results of differential scanning calorimetry measurements are showing decrease in enthalpy of gelatinization. The texture profile analyses of the starch gel prepared with suspension of TMA treated corn starch presented higher hardness, adhesiveness, cohesiveness, springiness and gumminess when compared with untreated suspension.