The effects of water, sorbitol and a sucrose fatty acid ester (SE) on the water sorption behaviour and thermal and mechanical properties of pullulan-based edible ®lms as well as the physiological responses of fruit coated with pullulan have been studied. Incorporation of sorbitol or SE in pullulan ®lms resulted in lower equilibrium moisture contents at low to intermediate water activities (a w ), but much higher moisture contents at a w > 0.75; estimates of monolayer values (within 4.1± 5.9 gH 2 O kg À1 solids) were given by application of the Brunauer±Emmett±Teller (BET) and Guggenheim±Anderson±DeBoer (GAB) models. A single glass±rubber transition (T g ), attributed to the polysaccharide component, was detected by calorimetry and dynamic mechanical thermal analysis (DMTA) at a sorbitol level of 15±30% DM. With both tests the strong plasticising action of water and polyol was evident in the thermal curves, and the T g vs moisture content data were successfully ®tted to the Gordon±Taylor empirical model. Multifrequency DMTA measurements provided estimates for the apparent activation energy of the glass transition in the range of Ä 300±488 kJ mol À1. With largedeformation mechanical testing, large decreases in Young's moduli (tensile and three-point bend tests) were observed as a result of water-and/or polyol-mediated glass-to-rubber transition of the polymeric ®lms. In the moisture content range of 2±8%, increases in¯exural modulus (E) and maximum stress (s max ) with small increases in moisture content were found for ®lms made of pullulan or pullulan mixed with 15% DM sorbitol; a strong softening effect was observed when the water content exceeded this range. Addition of sorbitol increased the water vapour transmission rate of the ®lms, whereas addition of SE had the opposite effect. Application of a pullulan/sorbitol/SE coating on strawberries resulted in large changes in internal fruit atmosphere composition which were bene®cial for extending the shelf-life of this fruit; the coated fruit showed much higher levels of CO 2 , a large reduction in internal O 2 , better ®rmness and colour retention and a reduced rate of weight loss. In contrast, similar studies on whole kiwifruits showed increased levels of internal ethylene, which caused acceleration of fruit ripening during storage.