Modern analytical techniques, in particular molecular biology techniques, can determine the plant or animal species present in a food-stuff. It is actually very difficult to determine the geographical origin of a food. The new European regulation 178/2002, applicable on January 1st, 2005 imposes this requirement for the traceability of food. This article gives a progress report on the physicochemical and microbiological analytical techniques available which make it possible to determine the origin of a food with some precision. © 2005 Elsevier Ltd. All rights reserved.