Gas transfer properties of wheat gluten (WG) coated paper and their ability to fulfil the requirements in eMAP of fresh parsley were studied. Permeation of gases through WG-paper was demonstrated to be RH-dependent and closely related to structural modification in the WG layer. Formation of micro-cracks was evidenced in dry conditions; but when increasing RH, plasticisation occurs within the protein layer and micro-fractures were reduced until disappearance. This reversible phenomenon allowed the WG-layer to recover its integrity at RH higher than 70%, and the WG character to be expressed in such conditions. When used at 20 degrees C and 80% RH as part of the packaging of parsley, modified atmosphere was created and a steady state of 11 kPa O-2 and 4.5 kPa CO2 was reached after 45 h. In such conditions, the overall quality of parsley leaves remained acceptable during 8 days, with only 28% loss of chlorophyll. (C) 2013 Elsevier Ltd. All rights reserved.