IJUP08 - Universidade do Porto

Formation of heterocyclic aromatic amines in charcoal grilled
sardines
M. Costa 1 , A. Melo 1 , C. Petisca 2 , I.M.P.L.V.O. Ferreira 1 , O. Pinho 1,2
1 REQUIMTE- Serviço de Bromatologia, Faculdade de Farmácia da Universidade do Porto, Rua
Anibal Cunha 164, 4099-030 Porto; Portugal
2 Faculdade de Ciências da Nutrição e Alimentação, Universidade do Porto, Rua Dr. Roberto Frias,
4200-465 Porto – Portugal
Heterocyclic Aromatic Amines (HAs) are produced during cooking at high temperatures of
proteinaceous food such as meat and fish [1]. HAs have proved to be carcinogenic in
animals and to induce early lesions in the development of cancer [1-2].
Grilling is considered a healthy method for cooking meat and fish, because foods do not
sear in a lot of fats. Grilled sardine Sardina pilchardus (Walbaum) is very appreciated by
Portuguese people, specially, during summer season. However, high temperatures can be
used during cooking and no studies were found concerning HAs’ formation. In the present
study, the effects of grilling on the formation of HAs of charcoal grilled sardines were
investigated.
Sardines were grilled in charcoal, under ordinary conditions (250-280 ºC) at two different
degrees of doness, “rare” and “well done”. Extraction and purification of HAs was
performed according to the method developed by Gross and Galceran [1-2] and adapted by
our research team [3]. The method uses the coupling of LLE with diatomaceous earth as
solid support and two SPE steps with propylsulfonic acid (PRS) and C18 was used to
extract HAs polar and less-polar HAs. Separation and quantification of HAs was
performed by liquid chromatography with diode array and fluorescence detection. All the
analytes were quantified by a standard addition method, using two fortified levels (around
5-20 ng g-1) and two non-spiked samples.
No HAs were quantified in “rare” grilled sardines, however, seven HAs, namely IQ,
MeIQx, PhIP, Trp-P-1, Trp-P-2, AαC, MeAαC were encountered in “well done” grilled
sardines. Nonpolar HAs (Trp-P2, AαC, MeαAC) and PhIP were the most abundant HAs in
“well done” grilled sardines. The presence of nonpolar HAs, Trp-P-1, Trp-P-2, MeαAC
and AαC is not often reported. Chemical modelling has shown that these HAs are
generated from pyrolysis of aminoacids via free radical reaction. These compounds have
been thought to be formed exclusively under extreme cooking conditions. Intake of
sardines is recommended owing to its high level of ω3 content, however, care should be
taken concerning the degree of doness.
References:
[1] Gross, G.A. (1990) Carcinogenesis (11) 1597- 1603.
[2] Galceran, M.T., Pais, P. and Puignou, L. (1996). Journal of Chromatography A (719) 203-212.
[3] Melo, A., Viegas, O., Eça, R., Petisca, C., Pinho O. and Ferreira I.M.P.L.V.O. (2008), Journal
of Liquid Chromatography & Related Technologies (31) 1–16.
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