Effect of Oxidative and Non-Oxidative Media on Coffee Torrefaction and Uncondensed-Gas Properties
DOI:
https://doi.org/10.25186/.v20i.2356Abstract
This research aims to examine the effect of atmospheric media variations on the uncondensed gas characteristics produced from the torrefaction and cooling processes of coffee beans. The process involved using air, N2, and Ar at a speed of 1 l/min as atmospheric media. Arabica green beans were torrefied for 60 min at 235±8oC and later cooled at the same rate and medium in a fixed-bed torrefier but stopped after the temperature reached 50oC. The volatile gases from the process flowed to the condenser, followed by the separation of the uncondensed gas from the liquid product, and subsequently flowed through the chimney. Furthermore, thermocouples that are connected to the Artisan visual roaster scope as an interface as well as the Artisan 2.4.2 software on a computer to measure and record changes in drum and bean temperatures (oC) over time (min). The uncondensed-gas yield was calculated
according to the mass balance principle, and their characteristics were determined directly in the form of temperature distribution (oC) and CO emission (ppm) by placing the testo 310 gas analyser sensor on the chimney. According to the findings, oxidative atmospheric caused greater temperature fluctuations in the drum and beans during the processes than non-oxidative media. The variations in atmospheric media led to differences in yield, and uncondensed-gas temperature distribution, as well as the CO emission. There was an increase in CO emission as the temperature was increased. The CO produced from torrefaction using non-oxidative is lower than using oxidative media. The cost factor and supporting of absorbent uncondensed-gas recycling technology must be taken into account when using non-oxidative media. This application will not only yield product variants but also reduce CO emissions and the coffee industry’s carbon footprint.
Key words: Arabica-green-bean; coffee torrefaction; nitrogen; argon; condenser.
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