Determination of formaldehyde in squid by high-performance liquid chromatography

Great attention has been paid to volatile toxic aldehydes like formaldehyde in aquatic products. In order to investigate content of formaldehyde in squid and squid products, a high-performance liquid chromatography (HPLC) method was developed for determination of formaldehyde. Based on steam distillation and 2,4-dinitrophenylhydrazine derivatization, formaldehyde was analysis by HPLC using ODS-C18 column at UV detector (355 nm). Detection limit was 8.92 microg/L in standard solution and 0.18 mg/kg in sample, and recovery was 83.09-103.20%. By this method, the formaldehyde content of squid muscle and viscera, dried squid thread and boiled squid were determined. The results showed that variable formaldehyde levels were observed among four species squid, which was generally far higher in viscera than in muscle of frozen squid. And cooking accelerated the formaldehyde production of squids. The study indicated that the HPLC method, with a better selectivity, precision and accuracy, was available to determine the formaldehyde in squid products with satisfactory results. Formaldehyde level in muscle and products of squid exceeded the formaldehyde limit by the Ministry of Agriculture in China.