GC x GC-TOFMS and chemometrics approach for comparative study of volatile compound release by tobacco heating system as a function of temperature

Tobacco heating products (THPs) are designed to heat tobacco to produce a nicotine-containing aerosol without combustion. Although THP aerosol is less complex mixture than cigarette smoking, there are a few reports related to the relationship between its chemical composition and its taste and aroma profiles. This study, therefore, aims to characterise the chemical composition of particulate phase aerosol (PPA) in a model THP system heated at different temperatures (100 degrees C; 150 degrees C; 200 degrees C; 240 degrees C; and 290 degrees C). The particulate phase of collected THP aerosol was extracted and analysed by GC x GC-TOFMS. The bidimensional total ion current (TIC) chromatograms were analysed using the SIMPLISMA algorithm, together with Principal Component Analysis (PCA) and Hierarchical Clustering Analysis (HCA) to extract key compounds. The semi-quantification was carried out based on similarity (Match), reverse match factor (R. Match) and linear retentions index (LRI). A total of 123 compounds responsible for important taste and aroma characteristics were identified and quantified in the model THP PPA. Although the concentration of compounds increased with the heating temperature, their release rate could be clustered into six groups based on HCA. Four of them, representing 92% of evaluated compounds showed a maximum release ratio at 290 degrees C, with distinct release behaviours that could fit into either linear, second order polynomial and exponential models. The purposed approach is useful for characterizing volatile compounds related to the taste and aroma profile in the THP system. In addition, these findings suggested that selecting a suitable heating temperature is a critical factor in THP system design in order to optimise tobacco taste and aroma.