Effect of fuel and kiln type on the polycyclic aromatic hydrocarbon (PAH) levels in smoked shrimp, a Beninese food condiment

Abstract

Smoked shrimp is a food condiment widely used in Beninese local cooking practices. A previous study revealed that this product is highly contaminated with polycyclic aromatic hydrocarbons (PAH). The present study explored possibilities to reduce PAH levels in shrimp smoked using cottage industry smoking techniques with barrel and chorkor kilns, by replacing wood by charcoal from Acacia auriculiformis and Mangifera indica, as fuels. Results showed that only shrimp smoked using acacia charcoal in a chorkor kiln had PAH levels (benzo[a]pyrene = 5 µg kg−1 and sum of benzo[a]pyrene, chrysene, benzo[a]anthracene and benzo[b]fluoranthene = 28 µg kg−1) in accordance with a European standard of 5 and 30 µg kg−1, respectively, and suitable physicochemical characteristics for good storage (moisture content = 11.9% ± 1.5%; water activity = 0.46 ± 0.03). However, further investigations still needs to be done to reduce the duration of product contact with combustion gasses in order to reduce the PAH content of smoked shrimp to safer levels, largely below standards.