Effects of different heating methods on pyrolysis and smoke release characteristics of tobacco granules

Heated tobacco products (HTPs) have gradually become an important development direction of tobacco products because of their significant advantages in reducing the release of harmful components. To reveal the thermal degradation characteristics of the heated tobacco products is of great significance for the development of novel heated tobacco products. The effects of heating method on pyrolysis and smoke release of the tobacco granules were studied with in situ diffuse reflection Fourier transform infrared spectroscopy (DRIFTS) technology and infrared thermal imaging technology. The results showed that: 1）The different heating methods of tobacco granules had a great influence on the temperature field distribution. Among them, the bottom heating method had a more uniform temperature distribution and a higher average temperature than the central heating method. 2) Different heating methods directly led to the difference in the release of various chemical components. The DRIFTS spectra indicated that the release characteristic of gaseous products with different heating methods were different, while the release temperature ranges were slightly different due to the differences of chemical components. The bottom heating method was more conducive to smoke release. 3) The moisture content of tobacco granules also directly affected the pyrolysis process and the smoke release characteristics. Either too high or too low moisture content was not conducive to the pyrolysis process and smoke release. The mathematical model of the thermal degradation characteristics was established to predict the quality of tobacco granules and to provide theoretical guidance for the product development of heating tobacco.