Abstract
Atomic absorption spectrophotometry was applied to the determination of copper in foods.
(1) Absorbancy at 324.8mμ was measured to determine copper.
(2) A linear relationship between an absorbancy and the concentration was found within the range of 0-20p. p. m. copper.
(3) Samples were burnt to ashes in an electric furnace at 550°C, and, after the ashes were dissolved with 5ml of 6N hydrochloric acid, 5ml of calcium chloride (2, 000p. p. m. Ca) were added and made up to 50ml with water. This solution was submitted to the analysis of copper.
(4) Chromium and tin interfered with the determination of copper fairly, but the interferences were eliminated by adding excess amount of calcium.
(5) Recoveries of copper added to the sample were found to be satisfactory.
(6) The reproducibility of analytical values was also satisfactory, that is, the coefficient of variation for copper was 3.3% for green peas.
(7) Contents of copper in raw and canned foods were about 0.1-2.0mg%, and the content of it in oysters was remarkably high in comparison with other fishes.
