Abstract: The invention relates to a dosimeter material for ammonia and/or amines, the indicator used, as well as processes for their manufacture and use, in particular for quality control of foodstuffs. The dosimeter material for ammonia and/or amines, in particular in the gas phase, comprises an indicator which undergoes an irreversible color change in the presence of ammonia and/or amines, and an immobilization matrix for the indicator that is permeable to ammonia and/or amines, wherein the immobilization matrix is water-impermeable, and wherein the indicator comprises a phosphorus porphyrin activated by covalent bonding to a silanol group and having the formula porphyrin-P(V)X3, wherein X is Cl or Br.