Roasting process of coffee beans as studied by nuclear magnetic resonance: time course of changes in composition
Feifei Wei1, Kazuo Furihata, Masanori Koda
1Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan.
Abstract:
In this paper, we report a (1)H and (13)C nuclear magnetic resonance (NMR)-based comprehensive analysis of coffee bean extracts of different degrees of roast. The roasting process of coffee bean extracts was chemically characterized using detailed signal assignment information coupled with multivariate data analysis. A total of 30 NMR-visible components of coffee bean extracts were monitored simultaneously as a function of the roasting duration. During roasting, components such as sucrose and chlorogenic acids were degraded and components such as quinic acids, N-methylpyridinium, and water-soluble polysaccharides were formed. Caffeine and myo-inositol were relatively thermally stable. Multivariate data analysis indicated that some components such as sucrose, chlorogenic acids, quinic acids, and polysaccharides could serve as chemical markers during coffee bean roasting. The present composition-based quality analysis provides an excellent holistic method and suggests useful chemical markers to control and characterize the coffee-roasting process.
More Related Videos
Related Concept Videos
Nuclear Magnetic Resonance (NMR): Overview
NMR spectroscopy generates a spectrum where the characteristic absorption frequencies of the sample are...
Atomic Nuclei: Magnetic Resonance
¹H NMR of Conformationally Flexible Molecules: Temporal Resolution
¹H NMR of Labile Protons: Temporal Resolution
The –OH proton in alcohols typically appears in the range of δ 2 to 5 ppm but can vary depending on the specific...
Atomic Nuclei: Nuclear Relaxation Processes
NMR Spectrometers: Radiofrequency Pulses and Pulse Sequences


