Coffee flavor chemistry: important volatiles for the gourmet coffees of Brazil

Abstract

Coffee is one of the most consumed and appreciated beverages in Brazil and the world, and its acceptance is associated with its unique taste characteristics and the chemical complexity of its volatile compounds. The term 'gourmet coffee' can be defined as a high-quality coffee, excellent and unique, with a balanced and fine flavor. In Brazil, the consolidation of the urban culture of coffee houses and gourmet coffee has aroused great interest mainly due to the high added value of this coffee. However, to the best of our knowledge, until now, there are no publications on the chemical composition of volatiles important to the flavor of Brazilian gourmet coffees. Therefore, the present research project aiming to characterize the volatile fraction of gourmet coffees samples using headspace solid-phase microextraction (HS-SPME) and gas chromatography coupled to mass spectrometry (GC-MS). The extraction efficiency of different commercial SPME fiber coating materials will be tested for its ability to capture volatiles from the samples. For the SPME fiber with better extraction efficiency, the time and temperature parameters of extraction will be optimized using multivariate response surface methodology. Once the optimal extraction conditions are known, the volatiles of seven Brazilian gourmet coffee samples will be characterized. It is believed that this research will enable the development of instrumental methods complementary to the sensorial evaluation, allowing the investigation of the relationship between the chemical composition of the volatile and the sensory perception of gourmet coffees by the consumers. (AU)