This article is an extended summary of the report prepared by the Integration of Hygienic and Aseptic Systems sub-group of The European Hygienic Engineering & Design Group (EHEDG). Originally published in March 2006, it is the 34th in the series of EHEDG summaries to be featured in TIFS. The full report prepared by R. Cocker (Chairman), S. Akesson, P.V. Bartels, A. Friis, H. Hoogland, G. Klimmeck, J. Oosterom, L.D. Steenstrup and J. Wilkinson is available from CCFRA at pubs@campden.co.uk. For information about EHEDG and to order papers please visit www.ehedg.org. The production of EHEDG guidelines is supported by the European Commission under the Quality of Life Programme; project HYFOMA (QLK1-CT-2000-01359).