Solid-state NMR spectroscopy of roasted and ground coffee samples: Evidences for phase heterogeneity and prospects of applications in food screening

Jair Freitas, Maryam Ejaz, Aline Toci, Wanderson Romao, Yaroslav Khimyak

Research output: Contribution to journalArticlepeer-review

Abstract

The advancement in the use of spectroscopic techniques to investigate coffee samples is of high interest especially considering the widespread problems with coffee adulteration and counterfeiting. In this work, the use of solid-state nuclear magnetic resonance (NMR) is investigated as a means to probe the various chemically-distinct phases existent in roasted coffee samples and to detect the occurrence of counterfeiting or adulterations in coffee blends. Routine solid-state 1H and 13C NMR spectra allowed the distinction between different coffee types (Arabica/Robusta) and the evaluation of the presence of these components in coffee blends. On the other hand, the use of more specialized solid-state NMR experiments revealed the existence of phases with different mo-lecular mobilities (e.g., associated with lipids or carbohydrates). The results illustrate the usefulness of solid-state NMR spectroscopy to examine molecular mobilities and interactions and to aid in the quality control of coffee -related products.
Original languageEnglish
Article number135317
Number of pages9
JournalFood Chemistry
Volume409
Early online date30 May 2023
DOIs
Publication statusAccepted/In press - 22 Dec 2022

Keywords

  • Solid-state NMR
  • Adulteration
  • Food composition
  • Roasted and ground coffee

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