The aim of this study was to produce resistant starch preparations from acid-modified coni starches prepared at various hydrolysis levels (0.5-4.0 hr). Effect of autoclaving cycles on resistant starch (RS) formation was investigated. Molecular weight distribution, pasting and functional properties of acid-modified corn starches were determined. For RS fort-nation native and acid-modified starch samples were gelatinized and autoclaved (1 or 2 cycles). While native and acid-modified starches did not contain any RS, the levels increased to 9.0-13.5% as a result of storage at 95 degrees C after first autoclaving cycle. Second autoclaving cycle together with storage at 95 degrees C brought final RS contents of the samples incubated at 4 and 95 degrees C after the first cycle to comparable level. As acid modification level increased, the amount of high molecular weight fractions decreased, resulting in significant decreases in viscosities (p < 0.05). The samples produced in this study had low emulsion stability and capacity values.