METHANOGENIC BACTERIA - PRESENCE IN FOODSTUFFS

Methanogenic bacteria are anaerobic, oxygen-intolerant microorganisms, and it is only by studying the different habitats of such bacteria th at fundamental information about their ecology becomes available. This research has evaluated methanogenic bacteria in apparently aerobic ec osystems, in foodstuffs not subjected to chemical-physical reclamation processes, where the presence of methanogenic bacteria has never been investigated. Methanogenic bacteria, ascribable to the Methanogenium, Methanobacterium and Methanosarcina genera, were found in vegetables, meat, fish and cheese but were generally absent in confectionery prod ucts and fruit. The microorganisms appear to be chance contaminants, u sually being present in only very low numbers. It should be noted that none of the tested foods showed the presence of Methanobrevibacter sm ithii, M. oralis or Methanosphaera stadtmaneae, methanogenic bacteria sometimes present in the human digestive tract.