Determination of calcium content in prawn meat using microwave digestion-flame atomic absorption spectrometry

The calcium content in prawn meatwas determined by using microwave digestion-flame atomic absorption spectrometry (FAAS), and the optimal conditions of microwave digestion and FAAS program were studied. The results show that the optimal amount of digestion reagent HNO3 is 5.0 mL when the sampling amount of prawn meat is 0.500 g. The optimal microwave digestion program for calcium determination in prawn meat is multistep digestion process D, which includes 3 steps: 1) power 400 W, ratio 100%, heat-up time 5 min, digestion temperature 120 ℃ for 5 min; 2) power 800 W, ratio 100%, heat-up time 5 min, digestion temperature 150 ℃ for 10 min; 3) power 800 W, ratio 100%, heat-up time 10 min, and digestion temperature 180 ℃ for 10 min. The calcium content in microwave-digested solution remains stable within 48 h. Under those conditions, the relative standard deviation (RSD) of determination is 5.284%, and therecovery of calciumis 91%~98%. The microwave digestion-FAAS method is rapid, accurate, economical and safe in determining the calcium content in prawn meat.