The invention provides a concentrated detergent composition comprising alkali metal carbonate, alkali metal percarbonate, and a peroxidation catalyst according to formula (I) [(LpMq)nXr]Ys, wherein each L independently is an organic ligand containing at least three nitrogen atoms that coordinate with the metal M; M is Mn or Fe; each X independently is a coordinating or bridging group selected from the group consisting of H2O, OH−, SH−, HO2−, O2−, O22−, S2−, F−, Cl−, Br−, I−, NO3−, NO2−, SO42−, SO32−, PO43−, N3−, CN−, NR3, NCS−, RCN, RS−, RCO2−, RO−, and with R being hydrogen or a C1 to C6 alkyl group; p is an integer from 1 to 4; q is an integer from 1 to 2; r is an integer from 0 to 6; Y is a counter ion; and s is the number of counter ions. The invention also relates to the use of said concentrated detergent composition as a warewashing detergent for the removal of starch soil.