A method for identifying tea leaf growth area differences through pure chemical shift NMR spectrums

Abstract

The invention relates to a method for identifying tea leaf growth area differences through pure chemical shift NMR spectrums. A PSYCHE pure chemical shift spectrum process and a multivariate statistical analysis process are combined and used for composition analysis of low-concentration natural food tea leaves. An obtained pure chemical shift spectrum is subjected to principal component analysis and an orthogonal partial least square analysis, growth area identification for tea leaves is achieved, and differential substances in the tea leaves of different growth areas are found out. The PSYCHEpure chemical shift spectrum process adopted by the method can remove broad-band homonuclear 1H-1H coupling, and only preserve chemical shift information so that a high-quality pure chemical shift hydrogen spectrum is obtained by applying the method to a low-concentration sample and the spectrum resolution is increased. A PSYCHE pulse sequence is simple, operation is easy, and conventional spectrometer conditions can meet experiment requirements. Compared with present tea leaf growth area identification methods, the NMR method provided is repeatable, non-invasive, high in spectrum resolution,and the like.

Description

technical field [0001] The invention relates to nuclear magnetic resonance spectroscopy detection technology, more specifically, relates to a method for identifying differences in tea production areas through pure chemical shift NMR spectroscopy. Background technique [0002] Tea is a popular drink with profound cultural heritage. In my country, tea is produced in a vast area, and tea itself is divided into green tea, black tea, white tea and other types. Different origins and types of tea have different tastes and values, and have obvious regional characteristics and quality characteristics. It is a typical geographical indication protection product. With more and more products protected by geographical indications of tea, there are more and more phenomena of counterfeit product labels and shoddy products, which have seriously violated market fairness, brand protection, and consumer rights. Therefore, the origin, authenticity and other identification of tea products are of...

AI Technical Summary

Problems solved by technology

[0008] At present, the pure chemical shift spectroscopy method of PSYCHE is only used to verify the decoupling effect of simple chemical samples, and has not been applied in the actual natural product samples with complex composition

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