Effect of rheological properties of composition based on modified starch on film formation

Abstract

This study investigated the use of carboxymethylated corn starch with sodium alginate for films preparation. The rheological properties as well as water absorption and mechanical properties of aqueous solutions and films of corn starch, carboxymethylated starch, sodium alginate and mixtures of starch and sodium alginate were studied. It was found that application of modified starch allows obtaining of water resistant films characterized by better physical-mechanical properties comparatively to the corn starch based films. It was found that mechanical strength of the formed films is due to the fact that alginate and carboxymethylated corn starch are hydrocolloids with an unbranched structure. This composition is characterized by stronger structure gels and higher viscosity of the solutions.