Dahl Lisbeth, Duinker Arne, Næss Synnøve, Markhus Maria Wik, Nerhus Ive, Midtbø Lisa Kolden, Kjellevold Marian
Department of Seafood and nutrition, Institute of Marine Research (IMR), NO-5817 Bergen, Norway.
Foods. 2020 Nov 12;9(11):1652. doi: 10.3390/foods9111652.
There is a lack of scientific evidence regarding the stability of iodine and mercury during cooking and processing of seafood. In this study, the iodine and mercury content were determined after thawing frozen fillets of Atlantic cod (), and further in raw compared to boiled, pan-fried, and oven baked fillets. Iodine was determined by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and mercury by atomic absorption spectrophotometry with Direct Mercury Analyzer (DMA-80). Thawing of the cod resulted on average in a 12% loss of iodine to the thawing water. Boiling significantly decreased the total content of iodine per slice of cod fillet corresponding to the concentration of iodine found in the boiling water. Pan-frying and oven-baking did not cause any significant changes of the total iodine content per slice of cod fillet, although iodine content per 100 g increased due to weight reduction of the cod slices from evaporation of water during preparation. For mercury, we found minimal changes of the different cooking methods. In summary, the findings in our study show that boiling had the greatest effect on the iodine content in the cod fillets. Type of cooking method should be specified in food composition databases as this in turn may influence estimation of iodine intake.
关于海鲜烹饪和加工过程中碘和汞的稳定性，缺乏科学证据。在本研究中，对解冻后的大西洋鳕鱼鱼片进行了碘和汞含量测定，并进一步比较了生鱼片与煮、煎、烤鱼片的含量。碘通过电感耦合等离子体质谱法（ICP-MS）测定，汞通过直接测汞仪（DMA-80）的原子吸收分光光度法测定。鳕鱼解冻后，平均有12%的碘流失到解冻水中。煮沸显著降低了每片鳕鱼片中碘的总含量，这与沸水中碘的浓度相对应。煎和烤并未导致每片鳕鱼片中碘的总含量发生任何显著变化，不过由于制备过程中水分蒸发导致鳕鱼片重量减轻，每100克的碘含量增加。对于汞，我们发现不同烹饪方法造成的变化极小。总之，我们的研究结果表明，煮沸对鳕鱼片中的碘含量影响最大。食品成分数据库应指明烹饪方法类型，因为这反过来可能会影响碘摄入量的估算。
