The effects of different concentrations of black pepper (0%, 0.5%, 1.0%, and 1.5%, wt/wt) and frying time (4, 8, and 12 min) on the contents of six heterocyclic aromatic amines (HAAs) were investigated in fried tilapia fillets. The level of total HAAs increased analogously with the increase in frying time, the total content of HAAs in fried tilapia fillets with or without black pepper ranged from 6.4 to 24.72 ng/g, and 10.43 to 33.19 ng/g, respectively. The inhibition rates of 1.0% of black pepper on 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐f] pyridine (PhIP) and 2‐amino‐3,8‐dimethylimidazo[4,5‐f] quinoxaline (MeIQx) levels were found to be 100% when the samples fried for 8 min, which were same as the samples fried for 12 min. The study demonstrated that 2‐amino‐3,4‐dimethylimidazo[4,5‐f] quinoline (MeIQ) and 9H‐pyrido[3,4‐b]‐indole (Norharman) were positively correlated with the degree of protein oxidation and that black pepper can greatly reduce the content of total HAAs.
Practical applications
Black pepper is often added for improving flavor in foods. Moreover, due to its antioxidant properties, it can be considered as one of safe and natural additives to inhibit HAAs formation. This is the first study about the inhibition of HAAs by adding black pepper in tilapia fillets before frying. The experimental results showed that black pepper was highly effective in inhibiting HAAs, and the addition of 1.0% of black pepper led to the greatest inhibition of total HAAs in fried fish fillets. A useful approach was provided through this study to control the formation of hazardous HAAs in fried fish products, which eventually help improve the safety and quality of fried aquatic products.