Effect of whey protein isolate-based edible films containing amino acids on the PhIP level and physicochemical properties of pan-fried chicken breasts.

Abstract

This study was conducted to investigate the inhibitory effects of edible films containing amino acids (AAs) on the formation of 2-amino-1-methyl-6-phenylimidazo [4,5-b] pyridine (PhIP) in chicken breasts and to evaluate the physicochemical properties of the chicken. Heated whey protein isolate (HWPI) solution (100 g) was made by heating 5 g whey protein isolate (WPI) solution at 90°C for 30 min in a water bath and subsequently mixed with 2.5 g glycerol (GLY), and tryptophan (Trp) or lysine (Lys) at 0.25%, 0.5%, and 0.75% concentrations. Unheated whey protein isolate (UHWPI)-based casting solution was prepared with the same method but without heating of WPI solution. Chicken breasts were cut at the same weights and were covered with the prepared edible films and fried at 195°C for 7.5 min. For edible films, total soluble matter (TSM%), color (calorimeter), radical scavenging activity (DPPH), and Fourier transform infrared spectroscopy (FTIR) were conducted. For chicken breasts, PhIP level, color before and after frying (calorimeter), cooking loss percentage (weigh loss before after frying), and tenderness (texture analyzer) were evaluated. The average PhIP level decreased from 78.47 ppb to 6.69-8.31 ppb for chicken covered with Lys-containing HWPI edible films, and to 25.82-46.80 ppb for chicken covered with Trp-containing ones. For chicken covered with UHWPI edible films, the PhIP decreased 28.4-56.04 ppb for Trp-containing ones and 19.67-40.32 ppb for Lys-containing ones. Moreover, chicken breasts covered with HWPI edible films had lower cooking loss and improved tenderness compared to the chicken breasts with no edible film. This study provides a new approach to decrease the PhIP levels in fried chicken breast.