Plasticizing and antiplasticizing effects of glycerol and sorbitol on biodegradable cassava starch films

Angélica Aimoto Shimazu, Suzana Mali, Maria Victória Eiras Grossmann

Abstract


In this work were studied the plasticizing – antiplasticizing effects of glycerol and sorbitol on moisture sorption and mechanical properties of cassava starch films. Films were produced by casting with cassava starch (3g starch/100 g filmogenic solution) and different concentrations of glycerol or sorbitol (0, 5, 10, 15, 30 and 40 g/100 g starch). Glycerol and sorbitol acted as antiplasticizers when used at a low concentration (?15 g/100 g starch) and low values of water activity (?0,58). The antiplasticizing effect could be demonstrated by the decrease in hydrophilicity and in flexibility of the films at these conditions. At higher concentrations and higher water activity values, the employed plasticizers exerted its plasticizing effect.


Keywords


Antiplasticization; Cassava starch.



DOI: http://dx.doi.org/10.5433/1679-0359.2007v28n1p79

Semina: Ciênc. Agrár.
Londrina - PR
E-ISSN 1679-0359
DOI: 10.5433/1679-0359
E-mail: semina.agrarias@uel.br
Este obra está licenciado com uma Licença Creative Commons Atribuição-NãoComercial 4.0 Internacional