Determination of sodium tripolyphosphate in meat samples by capillary zone electrophoresis with on-line isotachophoretic sample pre-treatment

The usefulness of zone capillary electrophoresis (CZE) in combination with isotachophoresis (cITP) as on-line preconcentration technique was examined for analysis of tripolyphosphate (STPP) in meat and meat products. The mean concentrations of STPP in different types of meat products varied from 39 mg P2O5/100 g to 219 mg P2O5/100 g, these values are below the legal requirements. The detection (LOD) and quantification (LOQ) limits for STPP in extracted solutions were 0.80 mg P2O5/dm3 and 2.69 mg P2O5/dm3, respectively. Obtained results were compared with the Kjeldahl method. Accuracy (97.4–98.3%) was determined using recovery assay based on standard additions method. Precision was evaluated by within-day R.S.D. (1.40–2.19%), between-days R.S.D. (3.00–3.82%) and demonstrates the benefit of using this procedure for the routine analysis of STPP in meat and their products. The F-Snedecor test was employed to compare the precision of the used methods and calculated F-test values (4.00, 6.13) were less than the theoretical (6.39).