Comprehensive chemical compound profiling of coffee powder fermented with tropical fruits pulp as a substrate

Abstract

This research aimed to identify the chemical compounds of the extract of Arabica coffee powder obtained through fermentation utilizing tropical fruit substrates using GC–MS and to compare the compound profiles obtained from hexane and ethanol extractions. Cherry coffee fruit beans were fermented with orange and tamarillo pulp, then dried, ground with a moisture content of 12%, and extracted using a Soxhlet with hexane and ethanol as solvents, and then were analyzed using Gas Chromatography–Mass Spectrometry (GC–MS). GC–MS analysis showed that both the fruit substrate and the extraction solvent influenced the resulting chemical profiles. Hexane extraction of orange-fermented coffee revealed non-polar compounds such as hexadecenoic acid methyl ester, 9-octadecenoic acid methyl ester (E), and several phthalates. Ethanol extraction produced a richer profile, dominated by fatty acid ethyl esters (FAEEs), including ethyl palmitate, linoleic acid ethyl ester, ethyl oleate, and ethyl stearate, alongside caffeine. Tamarillo-fermented samples displayed similar patterns of FAEEs in ethanol extracts and additionally contained 9,12-octadecadienoyl chloride (Z,Z). A notable finding was the presence of Patchouli alcohol exclusively in the hexane extract of tamarillo -fermented coffee, suggesting that fermentation facilitated the formation of unique terpenoid derivatives.

Keywords: coffee powder, fermentation, GC-MS, tropical fruits, chemical compounds