Flue gas analysis of apple and grey alder wood pellets in a meat smokehouse chamber

Abstract

The use of the smoke released during the wood burning process to prepare food products is a centuries-long tradition, practically all over the world. However, during the combustion process, a group of compounds called polyaromatic hydrocarbons (PAHs) are formed in the flue gases, which are carcinogenic and condense during the smoking process and diffuse into the smoked food product. Therefore, permissible PAH norms have been set for food producers, which significantly complicate the use of wood. In the study, using a gas analyzer, we measured the flue gases released during the burning of specially made, apple and gray alder wood pellets, with and without enrichment of the supplied air with ozone. The use of ozone does not ensure a higher burning temperature of pellets, but it stabilizes it – temperature fluctuations are significantly wider using non-ozonated air (697 to 817 and 611 to 817 ℃, respectively). The content of CO2, CO, as well as CH4 and N2O increases significantly in apple wood flue gases using ozonated air, while CH4 increases and N2O decreases in gray alder smoke. Which generally indicates specific reactions with ozone during combustion. Comparing the flue gases released during the burning of apple and grey alder wood pellets, grey alder smoke contains significantly more N2O and CO2 than apple wood pellet flue gases. On the other hand, using ozonated air in the combustion process increases N2O significantly in the flue gas of apple tree pellets compared to white alder.