Comparative Evaluation of the Volatile Profiles and Taste Properties of Commercial Coffee Products Using Electronic Nose, Electronic Tongue, and GC/MSD

Abstract

This study investigated taste and aroma characteristics of 10 commercial coffee samples using an electronic tongue (E-tongue), an electronic nose (E-nose), gas chromatography-mass spectrometry (GC/MSD), and GC-olfactometry (GC-O). In electronic tongue analysis, sourness, umami, and bitterness were high in the non-franchise#2 (N-FC#2), saltiness was high in the franchise#1 (FC#1), and sweetness was high in the non-franchise#4 (N-FC#4). In the electronic nose analysis, a total of 22 volatile compounds were identified in the 10 coffee samples, and 3-methyl-1-butanol, 2-methyl furan, and propan-2-one were the dominant content in these samples. In GC/MSD with GC-O analysis, a total of 40 volatile active compounds were identified, which include 3 alcohols, 2 aldehydes, 3 esters, 3 furans, 5 hydrocarbons, 5 heterocyclics, 4 ketones, 6 pyrazines, 5 pyrroles, 2 pyridines, and 2 phenolic compounds. Pyrazines were the dominant volatiles in the samples. 1-(2-Furanylmethyl)-1H-pyrrole was detected in all samples and showed a relatively higher content compared to other pyrroles. Our results which included taste and aroma patterns in commercial coffee brands may provide basic research data for the chemosensory research field.

Chemical sensory investigation in green and roasted beans Coffea arabica L. (cv. Yellow Bourbon) by various brewing methods using electronic sensors

“…Between each analysis, the sensor was washed with purified water to reduce potential cross contamination. The measured values of each extract were used to determine the patterns of taste compounds across samples using principal component analysis (PCA) (Boo et al., 2021).…”

“…The retention indices were based on the Kovats index library, and the compound indicated by each separated peak was determined using the AroChemBase (Alpha MOS) electronic nose. The measured values of the extracts were used to determine the patterns of VACs across the samples via PCA (Boo et al., 2021).…”

“…Recently, the number of studies of the flavor characteristics of food materials using an electronic tongue or nose increased considerably (Boo et al., 2021; Dong et al., 2019). Electronic tongue analysis is advantageous in that numerous samples can be analyzed simultaneously, while the electronic sensor enables rapid, objective, and quantified measurements of sensitivity to taste compounds in foods.…”

“…Electronic nose analysis, as in electronic tongue analysis, enables the simultaneous analysis of samples based on the identification of volatile aromatic compounds (VACs) in foods. Electronic tongue and nose analyses do not require complex pretreatment steps; thus, they are widely used (Boo et al., 2021; Cho et al., 2020).…”

CHAPTER 33. Coffee Volatile and Aroma Compounds – From the Green Bean to the Cup

“…Los sensores W1S (hidrocarburos de cadena corta) y W2S (alcoholes), presentaron rangos de conductancia similares para las muestras de café por origen. Hidrocarburos de cadena corta se ha identificado en cafés comerciales (Boo et al, 2021), en evaluaciones de cafés en cápsulas con la presencia de tolueno y granos de café verde fermentados . Granos de café verdes y tostado contienen una cantidad apreciable de hidrocarburos alifáticos, probablemente derivados de la oxidación de lípidos de café verde durante el almacenamiento o transporte previo al tueste .…”