Original research articleControl of phosphate levels in seafood products from the Portuguese market: Is there a need for concern?

•Natural phosphates levels were determined in 12 seafood species.•Limits of natural variation of phosphates allow estimating added phosphates.•New phosphates:protein ratios were proposed for 12 seafood species.•In general, added phosphates in processed products were within legislated values.•Legislation on total phosphate contents could be more appropriate for its control.

High consumption of phosphates, particularly added inorganic phosphates, may be associated with several health problems and so comprehensive data on their content in food, especially seafood, is of utmost importance. This work aimed to characterize phosphates contents in seafood products from the Portuguese market. Almost 900 samples of unprocessed and processed species of crustaceans, molluscs, and fish were analyzed at the Portuguese Institute for the Sea and Atmosphere over a 15 years' time period. Considering processed products, crab sticks presented the lowest average values of total phosphates, while salted and dry cod, hake and shrimp evidenced the highest variations. Phosphates contents in unprocessed samples varied among species, being the lowest and highest average values observed for octopus and sardine, respectively. New reference phosphate limits were defined which permits verifying if the legislation is followed with respect to phosphates added to seafood. Moreover, the reference conversion factor is not adequate for seafood, and thus new factors were proposed. Overall, the addition of phosphates has not been a current practice. Nevertheless, for an easier control and to avoid the need of laborious sampling to establish natural phosphates levels, it would be more appropriate to define limits with respect to total phosphates contents.