Introduction of Fatty Acids to Starch Granules by Ultra-High-Pressure Treatment

Introduction of fatty acid into maize starch granule by ultra high pressure treatment (UHPT) was investigated. Starches are normal, waxy and amylo-species. They were treated by ball-mill before UHPT. Fatty acids are linoleic, oleic and oleic-stearic acid mixtures. Removal of oil on granule surface was done with 50% ethanol. The incorporated amount of fatty acids and tendency of effect of ball-mill time on the fatty acid amount are different among the three starch species. Fatty acid introduction to amylose and amylopectin helices was also investigated after washing with chloroform-methanol-water mixture. The introduced fatty acid amount to amylostarch is the largest among three species. It is proved that the less double bond in fatty acid, the more fatty acid introduced to starch. The peak at 13.6° (2T) on X-ray diffraction pattern of starch samples treated by UHP becomes large and their Tp on DSC becomes low as increase of introduced fatty acid.