This method can be extended to foods not listed in Table 2, but recovery and
interference properties must be evaluated. Of particular importance is the maximum
safe analytical portion for microwave digestion, which depends on food composition
(Dolan, 1998). There is danger of the microwave vessel bursting from excessive
pressure if a very large quantity of food mass is used. High fat foods (mayonnaise,
butter, etc.) should be limited to a relatively small analytical portion. Dry foods
(cereal, bread, etc.) should be limited to smaller portions compared to high moisture
foods (radish, pear, etc.). The minimum analytical portion to insure a representative
sampling depends on the degree of analyte homogeneity.