The rheology of tomato seed protein isolate films at the corn oil-water interface

Tomato seed proteins adsorbed at the corn oil-water interface formed, after long ageing times, interfacial films with viscoelastic properties. The viscoelastic parameters of the films, derived by analysis of creep compliance-time curves, were markedly influenced by the aqueous phase protein concentration and showed maxima at a certain concentration which probably corresponded to monolayer saturation coverage. Tomato seed protein film viscoelasticity is greater than that of soybean protein, the parameters of which also show maxima at certain protein concentration. The lowering of pH brings about a decrease in tomato seed protein film viscoelasticity, a fact that could be the result of less molecular unfolding and consequently, less extensive intermolecular hydrophobic interaction.