the redox potential change was measured after incremental additions of the prepared starch samples to the potassium triiodide solution.A stable senson respnse was obtained within a few seconds because of the high ionic strength of the investigated solutions. The results for the responses of the model starch over the concentration range 1-5 g/l are shown in Fig.1 (some curves presented are displaced vertically for clarity).For further investigations,a starch solution with this concentration exhibited the greatest change in potential as the amount of added starch was increased.This characteristics is used for further analysis.