The invention relates to a composition comprising a mixture of at least two iscom complexes each complex comprising essentially one saponin fraction from Quillaja saponaria Molina. The complexes may be iscom complexes or iscom matrix complexes. The invention also pertains to the use of such a mixture for the preparation of an immunomodulating pharmaceutical, and adjuvant, formulations for immunization, e.g. for production of monoclonal antibodies, and a vaccine. Kits of parts comprising at least two parts, wherein each part comprises one iscom complex or one iscom matrix complex according to the invention are also embraced.