A process for the preparation of histaminase, respectively a histaminase containing material, is described. Histaminase is a diamine-oxidase which metabolizes histamine.According to the process at least one microorganism which produces in its cells histaminase, is cultivated and as soon as a sufficient number of microorganisms has grown, the microorganisms are isolated from the culture medium. Adhering culture medium is removed from the microorganisms and the microorganism cells are broken up and comminuted.The product can be dried in the vacuum, cooled and stored or it can be used to produce products having a higher content of histaminase or to produce a pure histaminase.Preferably a mixture of microorganisms is cultivated which contains at least one microorganism selected from the group lactobacillus and at least one yeast selected from the group candida.The histaminase containing products, respectively the histaminase, are used for metabolizing histamine in foodstuffs, beverages and forages yielding corresponding histamine free products in which the histamine had been metabolized forming not harmful metabolization products.