Role of Histidine and Tyrosine Decarboxylases and Mono- and Diamine Oxidases in Amine Build-Up in Cheese

Abstract

Presence of biologically active amines in foods has been recognized for about 20 years. Past research on amines such as tyramine and histamine has not investigated factors which account for the variable concentrations often found in food products. This research was designed to investigate the roles of tyrosine and histidine decarboxylase activities and mono- and diamine oxidases (MAO and DAO) in amine formation and catabolism in cheese. The data indicate that the presence of decarboxylases is probably not the limiting factor for amine build-up. Most cheeses contained decarboxylase activities for both tyrosine and histidine; however, tyramine and histamine were present in some cheeses which did not contain detectable levels of the corresponding decarboxylases at the time of sampling. Few cheeses possessed MAO or DAO activities. When the oxidases were present, the amine contents were usually lower. A Colby cheese containing tyramine and histamine with high MAO activity also possessed high tyrosine decarboxylase activity. It appears that a major limiting factor in formation of biologically active amines in cheese is the availability of free amino acids for decarboxylation. Dairy-related bacteria generally lacked the amine oxidases. However, five of six dairy-related cultures with highly active decarboxylases showed MAO or DAO activities. The culture showing the highest DAO activity, Microbacterium lacticum, possessed low tyrosine and histidine decarboxylase activities.