Enhancing the inhibitory effect of epigallocatechin gallate on formation of heterocyclic amines via protein complexation.

In order to enhance the inhibitory effect of epigallocatechin gallate (EGCG) on heterocyclic amines (HAs) formation, five common types of proteins were selected to form complexes with EGCG. The results indicated that the EGCG-β-lactoglobulin (β-Lg) complex had the strongest inhibitory effect on HAs in both chemical model systems and deep-fried pork meatballs. After optimizing the weight ratio of EGCG to β-Lg and the addition level, the contents of three targeted HAs, namely PhIP, MeIQx, and norharman, were significantly decreased by 64.2%, 61.6%, and 41.2% respectively, with only minor changes in the color, texture and taste of the meatballs. Fluorescence spectroscopy, fourier transform infrared spectroscopy and molecular docking studies revealed that hydrogen bonding and hydrophobic interactions were the main forces stabilizing the complexes, thereby improving antioxidant activity and thermal stability compared with free EGCG. These findings suggest that complexing EGCG with protein is a viable strategy for reducing HAs formation in high-temperature-processed meat products.