Quality analysis and characteristic difference identification of organic tea and conventional planting tea based on ICP, HPLC and machine algorithm

With the continuous expansion of the organic tea industry, distinguishing the authenticity of organic tea is crucial to maintain the market's stability. Thus, organic and conventional planting teas (green teas) of Dajianshan were selected as the objects in this study. The components (water extract, polyphenols, mineral element, etc.) were compared by high-performance liquid chromatography, inductively coupled plasma spectrometry, and mass spectrometry. The main difference substances were screened by multivariate statistical analysis methods (PCA, OPLS-DA, and LDA). Results showed significant differences in 37 of 51 components (<i>P</i> < 0.05). Statistical analysis showed 15 components (including amino acids, mineral elements, and catechins, VIP >1) that can be used as the characteristic differences between organic and conventional planting teas. The accuracy of the identification reached 93.9 %, providing a reference for the quality evaluation and identification of organic and conventional planting teas.