The classification of Wuyi rock tea (Oolong type) is performed by solid‐state nuclear magnetic resonance (NMR) for the first time. Quality differences of eight Oolong teas grown in Wuyi Mountains in southeastern China are analyzed by a combination of solid‐state 1H and 1H– 13C CP‐MAS (cross‐polarization magic angle spinning) NMR, partial least‐squares discriminate analysis (PLS‐DA), and quantitative descriptive analysis (QDA). The contents of caffeine, carbohydrate, polyphenol, and terpenoid were distinguished, and quantification of the metabolites was made based on the 1H and 13C MAS spectra. PLS‐DA shows a separation of high‐ and low‐quality Oolong teas, in good agreement with the result of QDA. These results indicate that NMR metabolomic approach enables us to differentiate the analyzed teas based on their chemical composition.

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The feasibility of ultrafast high-resolution intermolecular multiple-quantum coherence (UF-iMQC) spectroscopy for the direct analysis of molecular-mobility-restricted samples that are not suitable for magic-angle spinning, such as a jelly, hand soap, and marrow, is presented. Most components could be directly detected in their original state within 1 min without the need for tedious sample preparation processes. When we use conventional liquid nuclear magnetic resonance (NMR) method to study these systems, the spectral information could not be retrieved owing to the intrinsic inhomogeneous magnetic fields caused by sample inhomogeneity. In addition, the possibility for UF-iMQC-based quantifications is shown. The examples presented in this paper demonstrate the potential of UF iMQC NMR for food safety inspection, for quality testing of daily-life supplies, or in assisting medical diagnosis.