This paper presents some aspects of retardation and linear viscoelasticity of maize starch and guar gum water solutions. Frequently, the determination of material characteristic function, such as the molecular mass distribution of a polymeric sample, or the retardation spectrum of a viscoelastic fluid, leads to an ill-posed problem. The determination of the retardation spectrum, L(l), was analysed using data from a creep test. The linear viscoelasticity behaviour of maize starch and guar gum solutions was investigated as a function of time and biopolymer concentrations. The rheological experiments were performed using RheoStress RS150 rheometer. Using the regularization method, the retardation spectra were obtained by fitting the continuous Burger model.