Anti-plasticization of cassava starch by complexing fatty acids

The effect of adding 1-8% amylose complexing fatty acids (CFA), such as linoleic and oleic acids, on the glass transition temperature (Tg) of cassava starch (CS) with moisture content varying from 5 to 35% (dry basis) was studied. The main relaxation temperature (Tα), associated with the glass transition temperature of the samples (Tg), was determined by dynamic-mechanical-thermal analysis. The plasticizing behavior of water in the blends was evidenced by a decrease of Tα values with moisture content. The effect of CFA on CS was found to be a function of moisture content. At low moisture (<11%) it caused an anti-plasticization effect, while at higher moisture contents it produced plasticization. The anti-plasticizing effect of CFA on CS was attributed to amylose-lipid complex formation.