In this study, UPLC-MS/MS was used to study the effects of smoking duration and temperature on the formation of heterocyclic amines (HAs) in smoke-processed meat patties. Four kinds of free HAs—including F-7,8-DiMeIQx; F-MeAαC; F-Harman and F-Norharman—and six kinds of protein-bound HAs—including B-AαC; B-7,8-DiMeIQx; B-Glu-p-1; B-MeAαC; B-Harman and B-Norharman—were detected and quantified. Among the free HAs, we observed a 23-fold content increase (p < 0.05), from 0−4 h (at 0 h and 4 h they were 4.24 ng·g−1 and 98.33 ng·g−1, respectively), and the content of the free HAs decreased to 78.80 ng·g−1, at 5 h. At the same time, the free HAs content increased from 53.52 ng·g−1, at 50 °C, to 127.16 ng·g−1, at 60 °C, and then decreased continuously. The content of the free HAs was the highest at 60 °C. For the protein-bound HAs, their content was found to generally decrease with the increase in smoking duration and temperature. However, at 5 h, the content of protein-bound HAs slightly increased to 984.2 ng·g−1. Meanwhile, at 90 °C, it increased to 1643.53 ng·g−1. Additionally, a total of 16 volatile organic compounds (VOCs) were found in all of the meat samples, of which 10 VOCs (one acid, three aldehydes and seven phenols) were significantly related to the formation of free HAs. These findings showed that all the different types of HAs were produced under low-temperature processing, which provided scientific insights into the potential generation of HAs during meat smoking processes and could be used as a reference to minimize the risks of cancer related to the consumption of smoked meat products.
Keywords: UPLC-MS/MS; heterocyclic amines; meat patties; smoking durations; smoking temperatures; volatile organic compounds.