A simulation campaign, EXEMSI, organized by the ESA Long Term Programme Office was held from Sept. 7th to Nov. 6th 1992 in Germany. The crew- three men and one woman- was placed in confined and isolated living conditions in an hyperbaric chamber, thus simulating a space environment.During this two-month period, a nutritional investigation was conducted with a twofold objective: from an operational standpoint, to define and setup the food system; from a scientific standpoint, to collect data on the spontaneous nutritional behavior of the crew. In this scope, a well-defined food system was implemented. For food management and on line nutritional data collection, dedicated software has been developed. This software based on using barcodes permitted an accurate recording of food consumption for each crewmember. Nutritional assessments were then performed daily for each crewmember -or EMSInaut- by summing the nutritional values of all the foods consumed.This paper presents the main features of the food system for EXEMSI as well as the results of the nutritional investigation conducted.