Benzo(a)pyrene penetration on a smoked meat product during smoking time

The Codex Alimentarius gives recommendations to prevent carcinogenic polycyclic aromatic hydrocarbons (PAH) (represented by benzo(a)pyrene (BaP)) contamination during processing of meat products, including the control of smoking time. The influence of direct smoking time (0, 1, 3, 5 and 7 days) on the relationship between the BaP and moisture content of a typical Spanish smoked meat product called chorizo and the mechanism of BaP penetration and water release from four different depths in the product was studied. Chorizo was studied from the Principality of Asturias, a location never before tested. An analytical method was developed for this purpose consisting of PAH extraction assisted by sonication followed by solid-phase extraction (SPE) sample clean-up and analytical determination using GC-MS. Results show that an increase in smoking time produced contradictory and independent effects on the moisture and BaP content (mu gkg(-1)) of chorizos. The moisture content decreased from 49.9% to 31.3%. On the other hand, the BaP content increased from less than 0.24 mu gkg(-1) to 0.75 mu gkg(-1), finally stabilising after 5 days of smoking. After this time, the natural pores of the casing could be blocked by the large size tar particles from smoke, preventing the continued penetration of PAHs. The BaP content decreased and the moisture content increased progressively from the casing to the centre of the meat product. BaP mainly accumulated in the smoked casing, being four times in excess of the legal limit. This paper analyses the mechanism for preventing PAHs contamination during the process of smoking meat products.