Simultaneous Determination of Abietic Acid and Dehydroabietic Acid Residues in Duck Meat by HPLC-PAD-FLD

Abietic acid (AA) and dehydroabietic acid (DHAA) are major components of rosin, and both of them are well-recognized causes of skin allergy. Rosin was once widely used for removal of duck feathers in China. In the present study, an analytical method was developed for simultaneous determination of AA and DHAA in duck meats. AA and DHAA were extracted with acetonitrile and cleaned by solid-phase extraction, followed by chromatographic separation on C18 column with methanol/2 mM phosphoric acid (86/14, v/v) as mobile phase. AA was detected by photodiode array detection (PAD) at 240 nm, while DHAA was detected by fluorescence detection (FLD) with excitation and emission at 225 and 287 nm, respectively. Limits of quantification for AA and DHAA were 50 and 15 μg/kg, respectively. The method was applied to analysis of AA and DHAA residues in meats of rosin-defeathered ducks and commercial ducks. The results indicated that removal of duck feathers by means of rosin could lead to residues of AA and DHAA in duck skins, and 5 out of 32 commercial ducks were found to be contaminated by AA and DHAA, ranging from 1,556.1 to 9,638.7 μg/kg and 476.4 to 2,623.8 μg/kg, respectively. The proposed method could be used to identify those rosin-defeathered ducks and to monitor the illegal use of rosin in duck processing.