A non-hemolytic acidic composition comprising an immunoglobulin selected from immunoglobulin A, immunoglobulin G or immunoglobulin M at a pH value in the range of 4.65 to 5.7 comprising one or more excipients selected from amino acids, sugars and sugar alcohols in a concentration range of 100-350 mmol/l, in particular 200-350 mmol/l, characterized in that it displays an optical density (OD) in the range of 0.14 to -0.1 when the OD is determined in a spectrophotometer at 414 nm at a film thickness of 0.825 mm; and its use in an assay for determination of the hemolytic potential of intravenously applied pharmaceuticals and compositions and preparations displaying a reduced potential of hemolysis when being applied intravenously.