DETERMINATION OF P-TOLUENESULFONAMIDE IN ICE-CREAM BY COMBINATION OF CONTINUOUS-FLOW AND LIQUID-CHROMATOGRAPHY - SUMMARY OF COLLABORATIVE STUDY

A collaborative study of the determination of p-toluenesulfonamide (p- TSA) in ice cream by a combination of continuous flow and on-line liqu id chromatography was conducted. Seven ice cream samples containing D- 6-35 mg p-TSA/kg at 4 levels (1 blank and 3 pairs of split level sampl es) were analyzed by 11 laboratories. For all samples analyzed, the re peatability relative standard deviation varied from 2.08 to 3.67%, whe reas the reproducibility relative standard deviation ranged from 7.79 to 11.68%. The average p-TSA values for the split levels 1, 2, and 3 w ere 0.55, 1.02, and 4.44 mg p-TSA/kg, respectively, with mean recoveri es ranging from 76 to 79% (overall recovery range for all levels, 63-1 01%). No false positive results were reported for the blank sample, an d no interference was encountered by the presence of vanillin in sampl es. The method has been adopted first action by AOAC INTERNATIONAL.