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 treatm ent in lithium chloride/N,N-dimethylacetamide (DMAC) solution with acyl chl orides. Oleoyl, palmitoyl, lauroyl, capryloyl and butyryl modified starches have been synthesised with degrees of substitution (DS-values) ranging fro m 0.3 to 3. Characterisation by Fr-IR spectroscopy and elemental analysis h as confirmed reaction and degree of substitution obtained. DS-Values were c ontrolled by metered addition of stoichiometric quantities of the required acyl chloride. Such structural modification of starch resulted in a signifi cant change of physicochemical properties, and increased hydrophobicity wit h 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.