Non-precursors amino acids can inhibit β-carbolines through free radical scavenging pathways and competitive inhibition in roast beef patties and model food systems

Abstract

The aim of this study was to investigate the inhibitory effect of non-precursors amino acids (histidine, leucine, proline and methionine) which have advantages of safety, inexpensiveness and high standardization on the formation of β-carbolines in roast beef patties and glucose/creatine/creatinine/tryptophan model system, and the possible pathway of inhibition by monitoring the scavenging of free radicals by electron paramagnetic resonance (EPR) spectroscopy and the consumption of tryptophan by HPLC in a glucose/tryptophan model system. Almost all amino acids can inhibit β-carbolines in roast beef patties (up to 80.62%) and model system (up to 67.01%). Histidine showed an excellent alkyl radical scavenging ability (up to 82.59%) and a highly competitive inhibition ability (up to 65.60%) against β-carbolines generation. The corresponding abilities of leucine and methionine were less remarkable. Proline could only suppress β-carbolines through competitive inhibition. The results could shed light on the reduction of β-carbolines during meat processing.