Effect of different processing interventions on the residual level of formaldehyde in Fish

Formaldehyde, a potential carcinogen is used by fishermen and fish vendors to preserve the freshness and quality of fish and seafood because of its perishable nature. The present study evaluated the efficiency of different household culinary methods such as washing, boiling, and microwave cooking on the removal residual of formaldehyde from Indian Mackerel fish spiked with 1 % formaldehyde. In one experiment, the effect of washing on residual formaldehyde was evaluated by washing at different interval times of 2.5, 5, 7.5, 10, 12.5, and 15 minutes. The reduction level of formaldehyde was calculated using the HPLC method. The residual formaldehyde before different processing conditions in the fish ranged from 13.09 ± 0.099 µg g-1 to 12.86 ± 0.052 µg g-1. After washing, the residual formaldehyde was decreased to 3.74 ± 0.047 µg g-1. In washing, the percentage of absorption and removal of formaldehyde in fish after 15 minutes were found as 29.10% and 70.9% respectively. Another experiment was done in order to compare the effect of washing, boiling, and microwave cooking on the formaldehyde content in fish and found that formaldehyde content was reduced by 70.66 % in washing, 74.98% in boiling, and 50.196% in microwave cooking. Washing and boiling fish could significantly reduce the formaldehyde content in fish compared to microwave cooking.