Influence of the chemical and physical interactions in starch on material thermal properties.

摘要

Starch is an essential semi-crystalline biopolymer, which has numerous industrial applications in addition to food source. These applications completely depend on the amounts of intra- or inter-molecular interactions of starch molecules. This research investigates the role and nature of interactions of starch by the presence of probe molecules such as glycerol, TiO2 and cholesterol in different pH environments and thermal treatments. DSC was used to determine the strength and the amount of chain-chain interactions and, FTIR was used to follow the nature of these interactions in starch molecules. Results show that polar molecules, glycerol and TiO2 can interact with starch molecules to modify the thermal and physical properties of the starch. Non-polar molecule, such as cholesterol interacts with starch molecules in the presence of anions. These observations suggest that modification of chain --chain interactions of starch molecules can be done by the addition of glycerol, TiO2 and cholesterol at various pH conditions. These modifications may significantly alter physicochemical properties of starch as well as its application.