Effect of pH and Brewing Methods on Volatile Nitrogenous Compounds in Turkish Coffee

Kemal Sen; Fırat Can; Irmak Asi; Nadir Demirel

doi:10.57252/jrpfoods.2023.6

Authors

Kemal Sen Nevsehir Haci Bektas Veli University, Engineering-Architecture Faculty, Department of Food Engineering, Nevsehir, Turkey https://orcid.org/0000-0003-0781-6814
Fırat Can Kemalpaşa OSB Mahallesi Gazi Bulvarı DİMES Blok No: 181 İç Kapı No: 1 Kemalpaşa/ İzmir, Turkey https://orcid.org/0000-0001-8775-6254
Irmak Asi Department of Food Engineering, Faculty of Engineering and Architecture, Nevsehir Haci Bektas Veli University, 50300 Nevsehir, Turkey https://orcid.org/0000-0002-9039-4466
Nadir Demirel Department of Food Engineering, Faculty of Engineering and Architecture, Nevsehir Haci Bektas Veli University, 50300 Nevsehir, Turkey https://orcid.org/0000-0003-2782-4221

DOI:

https://doi.org/10.57252/jrpfoods.2023.6

Abstract

In this study, the changes in volatile nitrogenous compounds of Turkish coffee samples obtained using water with four different pH values (6.5, 7.5, 8.5, and 9.5) and three different brewing methods (cold brewing, traditional brewing, and machine brewing) were investigated. The extraction of volatile nitrogenous compounds was performed using the liquid-liquid extraction method. GC-MS technique was used for the quantification and identification of volatile nitrogenous compounds in Turkish coffee. These compounds were examined under three groups: pyrazines, pyrroles, and pyridines. In all samples of Turkish coffee obtained by all brewing methods, a total of 29 volatile nitrogenous compounds were identified, and it was found that 17 of them were pyrazines, 7 were pyrroles, and 5 were pyridines. The increase in pH values of the water used to obtain Turkish coffee generally increased the total amount of volatile nitrogenous compounds. Statistical analysis of the volatile nitrogenous compound data showed that both the change in pH value and the different brewing methods had a significant effect on Turkish coffee samples.