The iodine content of raw, boiled, pan‐fried, and oven‐baked fish samples using ICP‐MS: analysis and reliability of measurements

Abstract

SummarySince there is currently a lack of scientific evidence regarding the iodine content of raw and cooked fish, this study assesses that of various raw and cooked (boiled, pan‐fried, and oven‐baked) fish samples, using inductively coupled plasma‐mass spectrometry (ICP‐MS), following alkaline extraction. The iodine content of the raw fish is found to be highest in anchovy (295.9 ± 4.2 μg/100 g) and lowest in salmon (90.1 ± 3.1 μg/100 g) in dried weight. Boiling is found to reduce the iodine content in all of the fish samples significantly, except the bonito and salmon (P < 0.05). Meanwhile, the iodine content per 100 g is found to increase significantly in the pan‐fried and oven‐baked fish. The highest percentage of one serving of cooked fish meeting recommended iodine requirement were determined in oven‐baking haddock (351.0%), while the lowest percentage of one serving (150 g) of cooked fish meeting the recommended iodine requirement were determined in boiled garfish (70.9%). The best means of meeting the recommended daily iodine requirement in all the fish species evaluated, except bluefish, is found to be oven‐baking, while boiling has the greatest effect on reducing the iodine content. As a result, fish samples from the eastern Black Sea region of Turkey are good sources of iodine and it was determined that their iodine content changes when various cooking methods are used.