Analysis, Formation and Inhibition of Heterocyclic Amines in Foods: An Overview

Abstract

Heterocyclic amines (HAs), an important class of toxicological compounds, can be formed through heating of four precursors, amino acids, creatinine, creatine and sugars. Numerous studies have shown that most HAs are mutagenic and carcinogenic, and the safety of HAs-containing foods has become a major concern for the public. This paper deals with an overview of analysis, formation and inhibition of HAs in foods. Analysis of HAs from foods is routinely conducted by protein precipitation, followed by acid-base solvent partition, purification with column chromatography and identification and quantification by high-performance liquid chromatography (HPLC), or gas chromatography-mass spectrometry (GC-MS). However, most of these methods result in low recovery. With HPLC, all 16 HAs can be simultaneously separated by a binary or ternary gradient solvent system and detected by UV. Using fluorescence detection, only nine HAs can be detected. For GC-MS, only a number of HAs are separated and identified by employing a temperature programming method. GC-MS provides rapid identification and quantification of HAs in foods, however, this technique requires a time-consuming derivatization and the number of HAs separation is limited. Also, some HAs may degrade and result in peak tailing. The application of HPLC with photodiode-array detection (HPLC-DAD) can not only permit rapid identification and quantification of HAs, but also enhance sensitivity and selectivity. Broiling and frying are two major processing methods causing the formation of high amount of HAs. The formation of HAs in foods during cooking can be inhibited by incorporating additives such as antioxidants and amino acids. However, the results have been controversial. Further research is necessary to study the effect of various additives on inhibition of HAs formation in foods.