Wet gluten freshly washed out from grain of 4 Polish cultivars of high (Bombona and Zebra) and average (Bogatka and Finezja) baking value was subjected to heat treatment. 2-g gluten samples were placed in 2% NaCl water solution and heated for 15 minutes using following temperatures: ambient (22.5oC) and from 45 to 95oC, with a step by 5. After cooling (22.5oC), gluten samples were placed in a gap between heating plates with temperature of 150oC. The relative increments of gluten volume during expansion were determined using a digital camera. Experimental data were fitted by regression model that enabled to distinguish two types of expansion: the quasi-linear and hyperbolic ones, characterising viscous and elastic properties of gluten. Increase of heating temperature of gluten caused significant modifications of mechanical properties of gluten membranes. Temperature range from 75 to 95oC influenced the decrease increments of gluten volume as well as the lengthening of half-time of hyperbolic expansion. The volume increments were diminished by 0.1oC-1 While the hyperbolic expansion half-time extended from 32 to 37 s. Wheat cultivars of high quality, in comparison to the ones of average quality, were characterised by significantly shorter half-times of both types of expansion and higher increments of gluten volumes.