Heterocyclic Aromatic Amine Formation in Barbecued Sardines (Sardina pilchardus) and Atlantic Salmon (Salmo salar ) MARIANA COSTA, † OLGA VIEGAS, †,§ ARMINDO MELO, † CATARINA PETISCA, § OL ´ IVIA PINHO, †,§ AND ISABEL M. P. L. V. O. FERREIRA* ,† REQUIMTE, Servic ¸o de Bromatologia, Faculdade de Farma ´cia da Universidade do Porto, Rua Anibal Cunha 164, 4099-030 Porto, Portugal, and Faculdade de Cie ˆncias da Nutric ¸a ˜o e Alimentac ¸a ˜o da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal The formation of heterocyclic aromatic amines (HAs) during barbecuing of sardines (Sardina pilchardus) and Atlantic salmon (Salmo salar) to various degrees of doneness and grilling conditions was evaluated by HPLC-diode array (DAD)/fluorescence (FLD) detection. Additionally, the influences of charcoal and electric heat sources on formation of HAs in grilled salmon were compared. With regard to sardine samples barbecued at 280-300 °C, “rare” samples produced nondetectable amounts of HAs, “medium” sardines presented IQ, MeIQx, PhIP, and ARC at levels of 1.9, 4.4, 3.3, and 2.0 ng/g, respectively, and “well done” sardines presented IQ, MeIQx, Trp- P-1, Trp-P-2, PhIP, ARC, and MeARC at levels of 0.9, 2.2, 1.8, 8.2, 6.5, 17.7, and 10.6 ng/g, respectively. Different qualitative and quantitative profiles of HAs were observed in sardine and salmon samples cooked under similar conditions of temperature and doneness. Levels of 13.3, 3.5, 1.13, and 3.18 ng/g were obtained, respectively, for PhIP, ARC, MeARC, and Glu-P-1 in salmon samples barbecued at 280-300 °C. The contents of HAs were significantly higher in these samples than in salmon samples barbecued at 180-200 °C or in the electric device. However, MeIQx content (0.5 ng/g) was lower in salmon samples barbecued at 280-300 °C than in the other samples. KEYWORDS: Heterocyclic aromatic amines; sardines; salmon; HPLC; charcoal grilling INTRODUCTION The consumption of fish provides utilization of proteins of high biological value, certain minerals, and vitamins. Addition- ally, fish and fish oil are rich sources of omega-3 fatty acids, specifically eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (1). Over the past 20 years, there has been a dramatic increase in the scientific scrutiny of and public interest in fish consumption, omega-3 intake, and impact on personal health (1-9). Scientific data indicate that the consumption of fish or fish oil containing omega-3 polyunsaturated fatty acids (PUFAs) reduces the risk of coronary heart disease, lowers the incidence of diabetes, and plays a vital role in the development and function of the nervous system (brain) (8), photoreception (vision), and the reproductive system (9). Sardine (Sardina pilchardus) and salmon (Salmo salar) are fish species widely consumed and rich in omega-3 PUFAs, providing an adequate amount of these compounds (2.7-7.5 g per meal) (1, 2, 10). On the other hand, fish is usually cooked in different ways before consumption, and heat treatment can lead to undesirable modifications, such as the loss of nutritional value and formation of undesirable mutagenic and/or carcinogenic compounds such as heterocyclic aromatic amines (HAs), depending on the cooking method and fish preparation (11). Generally speaking, the types of cooking that involve temperatures of around 100 °C (boiling in water and steaming with or without previous browning) lead to a production of mutagenic agents that is too low to be quantifiable (12). However, grilling and barbecuing, the most common methods for preparation of fatty fishes, usually require high temperatures, and HAs are sometimes formed. Several studies show that charcoal-cooked meat presents higher amounts of these com- pounds (13). Fish sample studies are scarce but indicate a similar trend (14, 15). To date, about 20 carcinogenic/mutagenic HAs have been isolated and identified in cooked foods (16, 17). The achieved temperature has an important influence on the kind of HAs formed; the temperature that is needed for the formation of significant amounts of “thermic HAs”, or IQ type, is between 150 and 250 °C(Figure 1a). At higher temperatures, above 300 °C, the “pyrolytic HAs”, or non-IQ type, are formed preferably (Figure 1b)(18, 19). Factors reported to affect the * Author to whom correspondence should be addressed (telephone +351222078929; fax +351222003977; e-mail isabel.ferreira@ff.up.pt). † REQUIMTE, Servic ¸o de Bromatologia, Faculdade de Farma ´cia. § Faculdade de Cie ˆncias da Nutric ¸a ˜o e Alimentac ¸a ˜o. J. Agric. Food Chem. 2009, 57, 3173–3179 3173 10.1021/jf8035808 CCC: $40.75  2009 American Chemical Society Published on Web 03/06/2009