The effect of two different roasting process on the aroma and aroma-active compounds of Turkish coffee

In this study, Turkish coffee aroma and aroma-active compounds and effect of of the different roasting (medium roasted at 150-155 ° C and dark roasted at 165-170 ° C for 18 min) methods on these compounds were investigated. GC-MS-Olfactometry were used to determine aroma and aroma active compounds. Two different methods (liquid-liquid extraction and solvent assisted flavor evaporation technique:SAFE) were used to obtain aromatic extract from the coffee samples.According to sensory analysis (representivaness test) the aromatic extract obtained by SAFE extraction was representative of Turkish coffee. A total of 72 and 57 aroma components were identified in medium roasted and dark roasted Arabica coffee brews, respectively. Pyrazines and ketones were quantitatively the most dominant volatiles in Turkish coffee brew, followed by furans and phenols. With regard to aroma-active compounds 24 and 28 compounds were detected in medium roasted and dark roasted Arabica coffee brews, respectively. Within these, 2-ethyl-3-methylpyrazine (FDdark:2048), 2-ethyl-3,5-dimethylpyrazine (FDmedium:2048 and FDdark:1024), 3-methylbutanoic acid (FDdark:2048) and 2,3,5-trimethylpyrazine (FDmedium:512 and FDdark:1024) determined to be predominant aroma compounds based on their high flavor dilution (FD) factors by aroma extract dilution analysis (AEDA). Based on sensory analysis, Turkish coffee produced with medium roasted was the most preferred by panelists.