The preparation and characterisation of a series of chemically modified potato starches

A range of substituted starches has been prepared at moderate temperature (less than or equal to 90 degreesC) from gelatinised potato starch by treatment in lithium chloride/N,N-dimethylacetamide (DMAC) solution with acyl chlorides. Oleoyl, palmitoyl, lauroyl, capryloyl and butyryl modified starches have been synthesised with degrees of substitution (DS-values) ranging from 0.3 to 3. Characterisation by Fr-IR spectroscopy and elemental analysis has confirmed reaction and degree of substitution obtained. DS-Values were controlled by metered addition of stoichiometric quantities of the required acyl chloride. Such structural modification of starch resulted in a significant change of physicochemical properties, and increased hydrophobicity with increasing acylation extent. It was found that the modified starches had improved thermal stabilities and enhanced solubilities in organic solvents. (C) 2002 Elsevier Science Ltd. All, rights resented.