Effects of acetic acid on toxic metal content and proximatecomposition in the muscle of blood cockle (Anadara granosa)

Abstract

Blood cockle Anadara granosa is an important food source and one of the most commonly cultured species in the Mekong delta. But, cockle is a filter feeder, it can accumulate toxic metals from the water environment. This study aims conducted to evaluate the soaking effects of acetic acid in different concentrations at different times on the levels of Cd and Pb and proximate nutritional composition in the soft tissues. The levels of Pb in cockle tissue collected from Binh Dai district, Ben Tre province were over the permissible limits set by the European Commission (EC) and the Vietnamese Ministry of Health (MOH) (1.5 mg/kg). Concentrations of Cd in tissue were higher than the EC guideline of 1.0 mg/kg but lower than the MOH guideline of 2.0 mg/kg. The results showed that the removal efficiencies of two metals in cockle tissues with acetic acid were increased with increasing a range of acid concentration and soaking time. The highest removal efficiency of Cd and Pb was achieved with an acetic acid concentration of 5% and soaking in 15 minutes with minimum loss in the nutritive value of cockle tissue. After the soaking process, the levels of Cd and Pb in the tissue of the cockle were below the permissible limits recommended by the EC and the MOH.