Transport of NaCl solutions (0.001 M < C < 0.1 M) across isolated pepper cuticles in protonic form was studied. Cuticle characteristic parameters such as isoelectric point, resistance, salt permeability, concentration of fixed charge and cation transport number were determined. Cuticle asymmetry, due to its morphological heterogeneity, was detected from DC resistance and diffusion experiments. Biopolymer matrix resistance was determined (extrapolation at C = 0). A comparison of the results obtained with native pepper cuticles shows a more open structure for the pepper cuticle in protonic form.