Preparation and characterization of potato starch esters?.

JUAN I. MORÁN; VIVIANA P. CYRAS; ANALÍA VAZQUEZ

JOURNAL OF POLYMERS AND THE ENVIRONMENT

SPRINGER/PLENUM PUBLISHERS

Lugar: New York; Año: 2012 p. 1 - 10

1566-2543

The use of native starch as a thermoplastic polymer is limited by its fragility and highwater absorption. Due to the presence of several hydroxyl groups in its structure, wateracts as a natural plasticizer of starch, modifying its properties. For this reason, it isnecessary to chemically modify starch molecules by replacing hydroxyl groups withother functional groups to reduce water absorption. Chemical modification of starchgranules also alters its swelling and gelatinization behavior. In this contribution wedescribe the chemical modification of starch and its influence on its hydrophilicity andheat resistance. Acetic acid, maleic anhydride and octanoyl chloride were used asderivatizing reagents. The effectiveness of the treatments was evaluated by means ofinfrared spectroscopy. Different tests were conducted in order to evaluate theinfluence of chemical modification on starch structure and properties. Results showedthat the treatments effectively reduced starch moisture susceptibility, whilesubstantially altering other properties such as amylose content, swelling power,solubility, and heat resistance. Finally, films were prepared from native and derivatizedstarch and their mechanical properties and surface polarity was evaluated.