Microwave-Assisted Digestion Procedures Using Diluted Oxidant Mixture for Elemental Analysis of Crustaceans by MIP OES.

The aim of this study was to evaluate three digestion procedures using a diluted oxidant mixture of nitric acid, hydrogen peroxide, and water for determination of Cu, Fe, K, Mg, Mn, and Zn in shrimp and crab samples from Northern Brazil by microwave-induced plasma optical emission spectrometry. The efficiency of the digestion procedure was evaluated by comparing the residual carbon content, residual acidity, and elemental concentrations obtained in the samples. Digestion procedure 2 (4 mL HNO ₃  + 4 mL H ₂ O ₂  + 4 mL H ₂ O) was chosen due the adequate residual carbon content (5.85%) and low residual acidity (2.94 mol L ^-1 ). The recoveries obtained using the certified reference material (DORM-4) varied from 90 to 105%. High contents of K and Mg were found in the studied crustaceans. Also, it can give an excellent contribution to the recommended daily intake of Cu and Zn, indicating that these foods can be considered a good source of these minerals for the human diet.