A study of the heterogeneity and conformation in solution (in 70 % (v/v) aq. ethanol) of gliadin proteins from wheat was undertaken based upon sedimentation velocity in the analytical ultracentrifuge, analysis of the distribution coefficients and ellipsoidal axial ratios assuming quasi-rigid particles, allowing for a range of plausible time-averaged hydration values has been performed. All classical fractions (α, γ, ω slow , ω fast ) show 3 clearly resolved components. Based on the weight-average sedimentation coefficient for each fraction and a weight-averaged molecular weight from sedimentation equilibrium and/or cDNA sequence analysis, all the proteins are extended molecules with axial ratios ranging from ~10-30 with α appearing the most extended and γ the least.