Exploring different high-capacity tools and extraction modes to characterize the aroma of brewed coffee

Abstract

In the present work, the potential beneft of using multi-cumulative trapping headspace extraction was explored by comparing the results using solid-phase microextraction (SPME) coated with divinylbenzene/carboxen/polydimethylsiloxane and a probe-like tool coated with polydimethylsiloxane. The efciency of a single 30-min extraction, already explored in previous work, was compared with that of multiple shorter extractions. We evaluated three diferent conditions, i.e., three repeated extractions for 10 min each from diferent sample vials (for both the probe-like tool and SPME) or from the same vial (for SPME) containing brewed cofee. The entire study was performed using comprehensive two-dimensional gas chromatography coupled with mass spectrometry. The two-dimensional plots were aligned and integrated using a tile-sum approach before any statistical analysis. A detailed comparison of all the tested conditions was performed on a set of 25 targeted compounds. Although a single 30-min extraction using the probe-like tool provided a signifcantly higher compound intensity than SPME single extraction, the use of multiple shorter extractions with SPME showed similar results. However, multiple extractions with the probe-like tool showed a greater increase in the number of extracted compounds. Furthermore, an untargeted crosssample comparison was performed to evaluate the ability of the two tested tools and the diferent extraction procedures in diferentiating between espresso-brewed cofee samples obtained from capsules made of diferent packaging materials (i.e., compostable capsules, aluminum capsules, aluminum multilayer pack). The highest explained variance was obtained using the probe-like tool and multiple extractions (91.6% compared to 83.9% of the single extraction); nevertheless, SPME multiple extractions showed similar results with 88.3% of variance explained.