Estimating calcium in mechanically deboned poultry meat by oxidimetry and atomic absorption spectrophotometry

In samples taken over six months from 68 lots of mechanically deboned poultry meat, from several Dutch meat producers, average calcium content by atomic absorption spectrophotometry (AAS) was 2·36 g/kg. As AAS requires expensive equipment, laboratories less well equipped need something less sophisticated. A series of ten meat samples with increasing calcium content was analysed by two oxidimetric methods and by AAS. For in-plant quality control to a maximum calcium content of 2·5 g/kg the oxidimetric methods seemed sufficiently precise and repeatable because a confidence interval of 0·40 g/kg (P = 0·95) was found for analysis on duplicate subsamples. The relationship between the oxidimetric method of Peter (1966) and AAS could not be explained completely, whereas the oxidimetric method of AOAC corresponded well with AAS. There was a significantly (α = 0·01) higher correlation (r = 0·9996) between the AOAC method and AAS, so that the AOAC method is preferred more than that of Peter.