Three standard proteins-bovine serum albumin (BSA), ovalbumin (OVAL), and lysozyme (LYS)-were used to evaluate metal oxide adsorption isotherms. The isotherms of BSA adsorbed on powdered ZrO 2 and those of LYS adsorbed on pellets of ZrO 2 or spheres of Al 2 O 3 at pH 3.5 were well fitted by the Langmuir model. The adsorption curve of OVAL on powdered ZrO 2 showed an inflection point at the same pH. The adsorption curves obtained from the other systems (protein-metal oxide) were unfavorable. Protein adsorption of a white wine onto zirconium oxide showed adsorption selectivity. Zirconium had a preference for removing the unstable proteins, and that it could be used to stabilize white wines.

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