DETERMINATION OF DAMAGED STARCH IN WHEAT-FLOUR USING AN ELECTROCHEMICAL BIENZYME MALTOSE PROBE

The development of an electrochemical biosensor based on a bienzyme ma ltose probe and a third enzyme alpha-amylase in solution is reported f or the rapid and inexpensive determination of damaged starch. Analytic al parameters, such as probe stability, pH, temperature and response t ime, were optimised. Damaged starch was measured in the range of 5 x 1 0(-6) - 5 x 10(-4) mol/L as maltose produced by the enzymatic reaction and the detection limit was calculated according with the free maltos e and/or glucose in the sample. The damaged starch was determined in d ifferent wheat flours, and the data significantly correlated with thos e obtained using a reference procedure (r(2) = 0.994; P less than or e qual to 0.0001). In addition the results showed a comparable precision (CV < 5 %). This method is rapid, inexpensive and friendly for unskil led operators.